AMQPClassic Control

Properties   Methods   Events   Config Settings   Errors  

An easy-to-use AMQP 0.9.1 client implementation, with support for RabbitMQ extensions.

Syntax

AMQPClassic

Remarks

The AMQPClassic control provides an easy-to-use AMQP 0.9.1 client implementation, and it also supports certain RabbitMQ extensions to the AMQP 0.9.1 specification. The control supports both plaintext and TLS-enabled connections over TCP.

Connecting

The AMQP 0.9.1 transport protocol has two layers: an overall connection between the client and server, and one or more channels running over that connection.

The control implements both layers, so the first step is to initiate the overall connection. Set the AuthScheme, User, Password, SSLEnabled, and VirtualHost properties if necessary, then call the ConnectTo method, passing it the server's hostname and port number. (If the server in question is not running RabbitMQ, disabling the RabbitMQCompatible configuration setting before connecting is also recommended.)

The next step is to create at least one channel, which can be accomplished by using the CreateChannel method. The control allows creating any number of channels, up to the limit specified by the MaxChannelCount configuration setting.

Connecting and Creating a Channel // The examples in this documentation use a RabbitMQ server, which requires SASL Plain auth. amqpc1.AuthScheme = AmqpclassicAuthSchemes.smSASLPlain; amqpc1.User = "guest"; amqpc1.Password = "guest"; amqpc1.SSLEnabled = true; amqpc1.ConnectTo("amqpclassic.test-server.com", 5671); amqpc1.CreateChannel("channel");

Once the control has connected to the server, and one or more channels have been opened, the control can begin manipulating exchanges and queues, publishing messages, and creating consumers.

Note that most AMQP 0.9.1 operations can themselves vary in their complexity. The examples below are intentionally simple for the sake of clarity and brevity, but links are provided for many other parts of the control's API where more detail can be found.

Declaring Exchanges

The DeclareExchange method is used to declare (i.e., create, or verify the existence of) exchanges on the server. While all AMQP servers provide a default, direct-type exchange that all queues are bound to automatically (using their name as the routing key), more complex use-cases will often require creating additional exchanges of varying types.

Declaring an Exchange // Declare a direct-type exchange. amqpc1.DeclareExchange("channel", "MyExchange", "direct", false, false, false, false);

Exchanges can also be deleted using the DeleteExchange method.

Declaring Queues

The DeclareQueue method is used to declare (i.e., create, or verify the existence of) queues on the server. Unlike with exchanges, the server does not provide any queues by default, so declaring a queue is always necessary (unless one has already been created by another client, or configured ahead-of-time on the server itself).

Declaring a Queue // Declare a queue. amqpc1.DeclareQueue("channel", "MyQueue", false, false, false, false, false);

Queues may also be deleted or purged using the DeleteQueue and PurgeQueue methods.

Binding Queues to Exchanges

The BindQueue method is used to bind a queue to an exchange. Exchanges use the information held by their queue bindings to determine which messages to forward to which queues.

Note that all AMQP 0.9.1 servers automatically bind all queues to their default exchange (which is always a direct exchange with no name) using each queue's name as the binding's routing key. This makes it easy to send a message to a specific queue without having to declare bindings; just call PublishMessage, pass empty string for ExchangeName, and the name of the desired queue for RoutingKey.

Binding a Queue to an Exchange // Bind a queue to an exchange. Messages will only be delivered to the queue if their routing key is "MyRoutingKey". amqpc1.BindQueue("channel", "MyQueue", "MyExchange", "MyRoutingKey", false);

Queues can also be unbound from exchanges using the UnbindQueue method.

Publishing Messages

To publish a message, populate the Message* properties, and then call the PublishMessage method.

Publishing a Message amqpc1.Message.Body = "Hello, world!"; // Publish a message to the server's default (no-name) exchange, using the name of a specific queue as the routing key. amqpc1.PublishMessage("channel", "", "MyQueue", false, false); // Publish a message to the "MyExchange" exchange, using the routing key "MyRoutingKey". amqpc1.PublishMessage("channel", "MyExchange", "MyRoutingKey", false, false);

Note that outgoing messages may be handled differently by the server if the channel they are sent over is in transaction or (for RabbitMQ only) "publish confirmations" mode. Refer to the EnableTransactionMode and EnablePublishConfirms methods for more information.

Receiving Messages

There are two possible ways for the control to receive a message:

• Messages can be asynchronously pushed to the control from the server. At any point in time, the server may push a message to the control from a queue that the Consume method has been used to attach a consumer to.
• Messages can be synchronously pulled from the server by the control. The FetchMessage method is used to attempt to pull (or "fetch") messages from a specific queue.

Regardless of how they are received, all incoming messages cause the ReceivedMessage* properties to be populated and the MessageIn event to fire.

Receiving a Message // MessageIn event handler. amqpc1.OnMessageIn += (s, e) => { if (e.MessageCount == -1) { // The server pushed a message to us asynchronously due to a consumer we created. Console.WriteLine("The server pushed this message to us via consumer '" + e.ConsumerTag + "':"); Console.WriteLine(amqpc1.ReceivedMessage.Body); } else if (e.DeliveryTag > 0) { // We pulled a message from a queue with the FetchMessage() method. Console.WriteLine("Message successfully pulled:"); Console.WriteLine(amqpc1.ReceivedMessage.Body); Console.WriteLine(e.MessageCount + " messages are still available to pull."); } else { // We tried to pull a message, but there were none available to pull. Console.WriteLine("No messages available to pull."); } }; // Attach a consumer to "MyQueue". amqpc1.Consume("channel", "MyQueue", "consumerTag", false, true, false, false); // Or, try to fetch a message from "MyQueue". amqpc1.FetchMessage("channel", "MyQueue", true);

Note that the MessageIn event always fires if FetchMessage is called successfully, even if there were no messages available to fetch; refer to MessageIn for more information.

Property List

The following is the full list of the properties of the control with short descriptions. Click on the links for further details.

Method List

The following is the full list of the methods of the control with short descriptions. Click on the links for further details.

Event List

The following is the full list of the events fired by the control with short descriptions. Click on the links for further details.

Config Settings

The following is a list of config settings for the control with short descriptions. Click on the links for further details.

ArgumentCount Property (AMQPClassic Control)

The number of records in the Argument arrays.

Syntax

amqpclassiccontrol.ArgumentCount[=integer]

Default Value

0

Remarks

This property controls the size of the following arrays:

• ArgumentName
• ArgumentValue
• ArgumentValueType

The array indices start at 0 and end at ArgumentCount - 1.

This property is not available at design time.

Data Type

Integer

ArgumentName Property (AMQPClassic Control)

The table property's name.

Syntax

amqpclassiccontrol.ArgumentName(ArgumentIndex)[=string]

Default Value

""

Remarks

The table field's name.

This property specifies the table field's name. The name must be an ASCII string that:

• Starts with an ASCII letter, $, or $ character.
• Only contains ASCII letters, digits, underscores, $, and $ characters.
• Is unique among all sibling table field ArgumentNames.
• Is no longer than 128 characters.

The ArgumentIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ArgumentCount property.

This property is not available at design time.

Data Type

String

ArgumentValue Property (AMQPClassic Control)

The table property's value.

Syntax

amqpclassiccontrol.ArgumentValue(ArgumentIndex)[=string]

Default Value

""

Remarks

The table field's value.

This property specifies the table field's value.

The ArgumentIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ArgumentCount property.

This property is not available at design time.

Data Type

String

ArgumentValueType Property (AMQPClassic Control)

The table property's value type.

Syntax

amqpclassiccontrol.ArgumentValueType(ArgumentIndex)[=integer]

Possible Values

fvtBoolean(0), 
fvtByte(1), 
fvtUbyte(2), 
fvtShort(3), 
fvtUshort(4), 
fvtInt(5), 
fvtUint(6), 
fvtLong(7), 
fvtUlong(8), 
fvtFloat(9), 
fvtDouble(10), 
fvtDecimal(11), 
fvtSstring(12), 
fvtString(13), 
fvtArray(14), 
fvtTimestamp(15), 
fvtTable(16), 
fvtNull(17)

Default Value

17

Remarks

The table field's value type.

This property specifies the table field's value type (and thus, the format of the data in the ArgumentValue property). Acceptable value types are:

Note: The fvtUlong (8) and fvtSstring (12) value types are not supported when the RabbitMQCompatible configuration setting is enabled.

For the fvtArray (14) value type, the ArgumentValue should be specified as a JSON array of type-value pairs; for example:

[
  { "type": "int", "value": 23 },
  { "type": "int", "value": -52 },
  { "type": "int", "value": 153325 }
]

For the fvtTable (16) value type, the ArgumentValue should be specified as a JSON object containing name-type-value tuples; for example:

{
  { "name": "Test1", "type": "long", "value": 12345678901234 },
  { "name": "Test2", "type": "boolean", "value": "false" },
  { "name": "Test3", "type": "string", "value": "This is a test." }
}

Notes regarding fvtArray (14) and fvtTable (16) type ArgumentValues:

• All "type" fields in the JSON content must be set to one of the value types in the table above.
• For fvtTable (16) type ArgumentValues, all "name" fields must adhere to the rules described by the ArgumentKey documentation.
• Nesting and mixing multiple levels of arrays and tables in the JSON is allowed.

The ArgumentIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ArgumentCount property.

This property is not available at design time.

Data Type

Integer

AuthScheme Property (AMQPClassic Control)

The authentication scheme to use when connecting.

Syntax

amqpclassiccontrol.AuthScheme[=integer]

Possible Values

smNone(0), 
smSASLAnonymous(1), 
smSASLPlain(2), 
smSASLExternal(3)

Default Value

2

Remarks

This property controls what authentication scheme the control should use when connecting to the remote host.

Valid values are:

• smNone (0)
• smSASLAnonymous (1)
• smSASLPlain (2) - Default
• smSASLExternal (3)

This property is not available at design time.

Data Type

Integer

ChannelCount Property (AMQPClassic Control)

The number of records in the Channel arrays.

Syntax

amqpclassiccontrol.ChannelCount

Default Value

0

Remarks

This property controls the size of the following arrays:

• ChannelAccept
• ChannelMode
• ChannelName
• ChannelReadyToSend

The array indices start at 0 and end at ChannelCount - 1.

This property is read-only and not available at design time.

Data Type

Integer

ChannelAccept Property (AMQPClassic Control)

Whether the channel is currently accepting new messages from the server.

Syntax

amqpclassiccontrol.ChannelAccept(ChannelIndex)

Default Value

True

Remarks

Whether the channel is currently accepting new messages from the server.

This property reflects whether the channel is currently accepting new messages from the server. When the channel is created, this property is True by default.

The SetChannelAccept method can be used to disable and re-enable message acceptance at any time; refer to that method for more information.

The ChannelIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ChannelCount property.

This property is read-only and not available at design time.

Data Type

Boolean

ChannelMode Property (AMQPClassic Control)

What mode the channel is operating in.

Syntax

amqpclassiccontrol.ChannelMode(ChannelIndex)

Possible Values

cmtNormal(0), 
cmtTransactional(1), 
cmtPublishConfirms(2)

Default Value

0

Remarks

What mode the channel is operating in.

This property reflects what mode the channel is operating in. Possible values are:

• cmtNormal (0 - default): Normal mode.
• cmtTransactional (1): Transaction mode.
• cmtPublishConfirms (2): Publish confirmations mode.

All channels are in normal mode when they are created; there's nothing special about a channel in normal mode.

Channels can be put in transaction mode using the EnableTransactionMode method. While a channel is in transaction mode, all messages published and acknowledgements sent over it will be part of a transaction, and the server will wait to process them until the transaction is either committed or rolled back.

Channels can be put in publish confirmations mode using the EnablePublishConfirms method. While a channel is in publish confirmations mode, the server will acknowledge each message published by the control. The control will wait to fire the MessageOut event until it receives this acknowledgement. (Note that this mode is only available when the RabbitMQCompatible configuration setting is enabled.)

Note: Switching a channel to transaction or publish confirmations mode is a permanent action; the channel will then remain in that mode for the remainder of its lifetime.

The ChannelIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ChannelCount property.

This property is read-only and not available at design time.

Data Type

Integer

ChannelName Property (AMQPClassic Control)

The name of the channel.

Syntax

amqpclassiccontrol.ChannelName(ChannelIndex)

Default Value

""

Remarks

The name of the channel.

This property reflects the name of the channel.

The ChannelIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ChannelCount property.

This property is read-only and not available at design time.

Data Type

String

ChannelReadyToSend Property (AMQPClassic Control)

Whether the channel is ready to send a message.

Syntax

amqpclassiccontrol.ChannelReadyToSend(ChannelIndex)

Default Value

True

Remarks

Whether the channel is ready to send a message.

This property reflects whether the channel is currently ready to send a message or not.

The ChannelIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ChannelCount property.

This property is read-only and not available at design time.

Data Type

Boolean

ClientPropertyCount Property (AMQPClassic Control)

The number of records in the ClientProperty arrays.

Syntax

amqpclassiccontrol.ClientPropertyCount[=integer]

Default Value

0

Remarks

This property controls the size of the following arrays:

• ClientPropertyName
• ClientPropertyValue
• ClientPropertyValueType

The array indices start at 0 and end at ClientPropertyCount - 1.

This property is not available at design time.

Data Type

Integer

ClientPropertyName Property (AMQPClassic Control)

The table property's name.

Syntax

amqpclassiccontrol.ClientPropertyName(ClientPropertyIndex)[=string]

Default Value

""

Remarks

The table field's name.

This property specifies the table field's name. The name must be an ASCII string that:

• Starts with an ASCII letter, $, or $ character.
• Only contains ASCII letters, digits, underscores, $, and $ characters.
• Is unique among all sibling table field ClientPropertyNames.
• Is no longer than 128 characters.

The ClientPropertyIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ClientPropertyCount property.

This property is not available at design time.

Data Type

String

ClientPropertyValue Property (AMQPClassic Control)

The table property's value.

Syntax

amqpclassiccontrol.ClientPropertyValue(ClientPropertyIndex)[=string]

Default Value

""

Remarks

The table field's value.

This property specifies the table field's value.

The ClientPropertyIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ClientPropertyCount property.

This property is not available at design time.

Data Type

String

ClientPropertyValueType Property (AMQPClassic Control)

The table property's value type.

Syntax

amqpclassiccontrol.ClientPropertyValueType(ClientPropertyIndex)[=integer]

Possible Values

fvtBoolean(0), 
fvtByte(1), 
fvtUbyte(2), 
fvtShort(3), 
fvtUshort(4), 
fvtInt(5), 
fvtUint(6), 
fvtLong(7), 
fvtUlong(8), 
fvtFloat(9), 
fvtDouble(10), 
fvtDecimal(11), 
fvtSstring(12), 
fvtString(13), 
fvtArray(14), 
fvtTimestamp(15), 
fvtTable(16), 
fvtNull(17)

Default Value

17

Remarks

The table field's value type.

This property specifies the table field's value type (and thus, the format of the data in the ClientPropertyValue property). Acceptable value types are:

Note: The fvtUlong (8) and fvtSstring (12) value types are not supported when the RabbitMQCompatible configuration setting is enabled.

For the fvtArray (14) value type, the ClientPropertyValue should be specified as a JSON array of type-value pairs; for example:

[
  { "type": "int", "value": 23 },
  { "type": "int", "value": -52 },
  { "type": "int", "value": 153325 }
]

For the fvtTable (16) value type, the ClientPropertyValue should be specified as a JSON object containing name-type-value tuples; for example:

{
  { "name": "Test1", "type": "long", "value": 12345678901234 },
  { "name": "Test2", "type": "boolean", "value": "false" },
  { "name": "Test3", "type": "string", "value": "This is a test." }
}

Notes regarding fvtArray (14) and fvtTable (16) type ClientPropertyValues:

• All "type" fields in the JSON content must be set to one of the value types in the table above.
• For fvtTable (16) type ClientPropertyValues, all "name" fields must adhere to the rules described by the ClientPropertyKey documentation.
• Nesting and mixing multiple levels of arrays and tables in the JSON is allowed.

The ClientPropertyIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ClientPropertyCount property.

This property is not available at design time.

Data Type

Integer

Connected Property (AMQPClassic Control)

This property triggers a connection or disconnection.

Syntax

amqpclassiccontrol.Connected[=boolean]

Default Value

False

Remarks

This property triggers a connection or disconnection. Setting this property to True makes the control attempt to connect to the host identified by the RemoteHost property. If successful, after the connection is achieved, the value of the property changes to True and the Connected event is fired.

Setting this property to False closes the connection. How and when the connection is closed is controlled by the Linger property.

Note: It is recommended to use the Connect or Disconnect method instead of setting this property.

This property is not available at design time.

Data Type

Boolean

FirewallAutoDetect Property (AMQPClassic Control)

This property tells the control whether or not to automatically detect and use firewall system settings, if available.

Syntax

amqpclassiccontrol.FirewallAutoDetect[=boolean]

Default Value

False

Remarks

This property tells the control whether or not to automatically detect and use firewall system settings, if available.

Data Type

Boolean

FirewallType Property (AMQPClassic Control)

This property determines the type of firewall to connect through.

Syntax

amqpclassiccontrol.FirewallType[=integer]

Possible Values

fwNone(0), 
fwTunnel(1), 
fwSOCKS4(2), 
fwSOCKS5(3), 
fwSOCKS4A(10)

Default Value

0

Remarks

This property determines the type of firewall to connect through. The applicable values are as follows:

Data Type

Integer

FirewallHost Property (AMQPClassic Control)

This property contains the name or IP address of firewall (optional).

Syntax

amqpclassiccontrol.FirewallHost[=string]

Default Value

""

Remarks

This property contains the name or IP address of firewall (optional). If a FirewallHost is given, the requested connections will be authenticated through the specified firewall when connecting.

If this property is set to a Domain Name, a DNS request is initiated. Upon successful termination of the request, this property is set to the corresponding address. If the search is not successful, the control fails with an error.

Data Type

String

FirewallPassword Property (AMQPClassic Control)

This property contains a password if authentication is to be used when connecting through the firewall.

Syntax

amqpclassiccontrol.FirewallPassword[=string]

Default Value

""

Remarks

This property contains a password if authentication is to be used when connecting through the firewall. If FirewallHost is specified, the FirewallUser and FirewallPassword properties are used to connect and authenticate to the given firewall. If the authentication fails, the control fails with an error.

Data Type

String

FirewallPort Property (AMQPClassic Control)

This property contains the transmission control protocol (TCP) port for the firewall Host .

Syntax

amqpclassiccontrol.FirewallPort[=integer]

Default Value

0

Remarks

This property contains the transmission control protocol (TCP) port for the firewall FirewallHost. See the description of the FirewallHost property for details.

Note: This property is set automatically when FirewallType is set to a valid value. See the description of the FirewallType property for details.

Data Type

Integer

FirewallUser Property (AMQPClassic Control)

This property contains a user name if authentication is to be used connecting through a firewall.

Syntax

amqpclassiccontrol.FirewallUser[=string]

Default Value

""

Remarks

This property contains a user name if authentication is to be used connecting through a firewall. If the FirewallHost is specified, this property and FirewallPassword properties are used to connect and authenticate to the given Firewall. If the authentication fails, the control fails with an error.

Data Type

String

Heartbeat Property (AMQPClassic Control)

The heartbeat timeout value.

Syntax

amqpclassiccontrol.Heartbeat[=integer]

Default Value

0

Remarks

This property specifies the heartbeat timeout value, in seconds. Heartbeats are disabled if set to 0 (default).

Before connecting, this property can be set to indicate the desired heartbeat timeout value. During the connection process, the control and the server will compare their desired heartbeat values and choose the lower one.

Once connected, this property will reflect the agreed-upon heartbeat value. While the connection is idle, heartbeats are sent by both the control and the server approximately once every (Heartbeat / 2) seconds. If either side has not received a heartbeat (or other transmission) for ~Heartbeat seconds, it will consider the other side unreachable and close the connection.

This setting cannot be changed while connected.

This property is not available at design time.

Data Type

Integer

IncomingMessageCount Property (AMQPClassic Control)

The number of records in the IncomingMessage arrays.

Syntax

amqpclassiccontrol.IncomingMessageCount

Default Value

0

Remarks

This property controls the size of the following arrays:

• IncomingMessageAppId
• IncomingMessageBody
• IncomingMessageChannelName
• IncomingMessageContentEncoding
• IncomingMessageContentType
• IncomingMessageCorrelationId
• IncomingMessageDeliveryMode
• IncomingMessageExpiration
• IncomingMessageHeaders
• IncomingMessageId
• IncomingMessagePriority
• IncomingMessageReplyTo
• IncomingMessageTimestamp
• IncomingMessageType
• IncomingMessageUserId

The array indices start at 0 and end at IncomingMessageCount - 1.

This property is read-only and not available at design time.

Data Type

Integer

IncomingMessageAppId Property (AMQPClassic Control)

The Id of the application that created the message.

Syntax

amqpclassiccontrol.IncomingMessageAppId(IncomingMessageIndex)

Default Value

""

Remarks

The Id of the application that created the message.

This property holds the Id of the application that created the message. It may be empty if the message does not have an application Id set.

This value must be specified as a string no longer than 255 characters.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessageBody Property (AMQPClassic Control)

The message body.

Syntax

amqpclassiccontrol.IncomingMessageBody(IncomingMessageIndex)

Default Value

""

Remarks

The message body.

This property holds the body of the message. It may be empty.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

To read or write binary data to the property, a Variant (Byte Array) version is provided in .IncomingMessageBodyB.

This property is read-only and not available at design time.

Data Type

Binary String

IncomingMessageChannelName Property (AMQPClassic Control)

The name of the channel the message is associated with.

Syntax

amqpclassiccontrol.IncomingMessageChannelName(IncomingMessageIndex)

Default Value

""

Remarks

The name of the channel the message is associated with.

This property reflects the name of the channel which the message is associated with; it is populated automatically by the control.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessageContentEncoding Property (AMQPClassic Control)

The content encoding of the message's body.

Syntax

amqpclassiccontrol.IncomingMessageContentEncoding(IncomingMessageIndex)

Default Value

""

Remarks

The content encoding of the message's body.

This property holds the content encoding of the message's body. It may be empty if the message does not have a content encoding set.

This value must be specified as a string no longer than 255 characters.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessageContentType Property (AMQPClassic Control)

The content type (MIME type) of the message's body.

Syntax

amqpclassiccontrol.IncomingMessageContentType(IncomingMessageIndex)

Default Value

""

Remarks

The content type (MIME type) of the message's body.

This property holds the content type (MIME type) of the message's body. It may be empty if the message does not have a content type set.

This value must be specified as a string no longer than 255 characters.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessageCorrelationId Property (AMQPClassic Control)

The correlation Id of the message.

Syntax

amqpclassiccontrol.IncomingMessageCorrelationId(IncomingMessageIndex)

Default Value

""

Remarks

The correlation Id of the message.

This property holds the correlation Id of the message. It may be empty if the message does not have a correlation Id set.

This value must be specified as a string no longer than 255 characters.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessageDeliveryMode Property (AMQPClassic Control)

The delivery mode of the message.

Syntax

amqpclassiccontrol.IncomingMessageDeliveryMode(IncomingMessageIndex)

Default Value

0

Remarks

The delivery mode of the message.

This property holds the delivery mode of the message; possible values are:

• 0: Unspecified.
• 1: Non-persistent; the message may be lost if the server encounters an error.
• 2: Persistent; the message will not be lost, even in case of server errors.

The default is 0, which indicates that the message does not have an explicit delivery mode set.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

Integer

IncomingMessageExpiration Property (AMQPClassic Control)

The time-to-live value for this message.

Syntax

amqpclassiccontrol.IncomingMessageExpiration(IncomingMessageIndex)

Default Value

""

Remarks

The time-to-live value for this message.

This property specifies the time-to-live (TTL) value, in milliseconds, for this message. It may be -1 if this message does not have a TTL.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessageHeaders Property (AMQPClassic Control)

Headers associated with the message.

Syntax

amqpclassiccontrol.IncomingMessageHeaders(IncomingMessageIndex)

Default Value

""

Remarks

Headers associated with the message.

This property holds additional Headers associated with the message. It may be empty if the message does not have any headers set.

This property must be specified as a JSON object containing name-type-value tuples; for example:

[
  { "name": "Header1", "type": "long", "value": 12345678901234 },
  { "name": "Header2", "type": "boolean", "value": "false" },
  { "name": "Header3", "type": "string", "value": "This is a test." }
]

All "name" values must be ASCII strings that:

• Start with an ASCII letter, $, or $ character.
• Only contain ASCII letters, digits, underscores, $, and $ characters.
• Are unique among their siblings.
• Are no longer than 128 characters.

The following table describes all valid "type" values, and how to format the "value" field for each:

Note: The ulong and sstring value types are not supported when the RabbitMQCompatible configuration setting is enabled.

Headers of the table type should be specified in the same manner as shown above, while headers of the array type should be specified as a JSON array of type-value pairs; for example:

[
  { "type": "int", "value": 23 },
  { "type": "int", "value": -52 },
  { "type": "int", "value": 153325 }
]

Nesting and mixing multiple levels of arrays and tables is allowed.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessageId Property (AMQPClassic Control)

The unique Id of the message.

Syntax

amqpclassiccontrol.IncomingMessageId(IncomingMessageIndex)

Default Value

""

Remarks

The unique Id of the message.

This property holds the unique Id of the message. It may be empty if the message does not have a unique Id.

This value must be specified as a string no longer than 255 characters.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessagePriority Property (AMQPClassic Control)

The priority of the message.

Syntax

amqpclassiccontrol.IncomingMessagePriority(IncomingMessageIndex)

Default Value

0

Remarks

The priority of the message.

This property holds the priority of the message. Valid priority values are 0-9; any other value causes the message to have unspecified priority when sent.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

Integer

IncomingMessageReplyTo Property (AMQPClassic Control)

The address to send replies to for the message.

Syntax

amqpclassiccontrol.IncomingMessageReplyTo(IncomingMessageIndex)

Default Value

""

Remarks

The address to send replies to for the message.

This property specifies the address to send replies to for the message. It may be empty if the message does not have a specific reply-to address set.

This value must be specified as a string no longer than 255 characters.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessageTimestamp Property (AMQPClassic Control)

The message's timestamp.

Syntax

amqpclassiccontrol.IncomingMessageTimestamp(IncomingMessageIndex)

Default Value

0

Remarks

The message's timestamp.

This property holds the timestamp of the message, specified as milliseconds since the Unix epoch (January 1, 1970 00:00:00 UTC). It may be less than or equal to 0 (default) if the message does not have a timestamp set.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

Long64

IncomingMessageType Property (AMQPClassic Control)

The message's type.

Syntax

amqpclassiccontrol.IncomingMessageType(IncomingMessageIndex)

Default Value

""

Remarks

The message's type.

This property holds the type of the message. It may be empty if the message does not have a type set.

This value must be specified as a string no longer than 255 characters.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

IncomingMessageUserId Property (AMQPClassic Control)

The identity of the user responsible for producing the message.

Syntax

amqpclassiccontrol.IncomingMessageUserId(IncomingMessageIndex)

Default Value

""

Remarks

The identity of the user responsible for producing the message.

This property specifies the identity of the user responsible for producing the message. It may be empty if no specific user was responsible for creating the message.

A message's user Id may be used for verification or authentication by the server and/or the final consumer.

This value must be specified as a string no longer than 255 characters.

The IncomingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

LocalHost Property (AMQPClassic Control)

The name of the local host or user-assigned IP interface through which connections are initiated or accepted.

Syntax

amqpclassiccontrol.LocalHost[=string]

Default Value

""

Remarks

The LocalHost property contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multi-homed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the control initiate connections (or accept in the case of server controls) only through that interface.

If the control is connected, the LocalHost property shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).

NOTE: LocalHost is not persistent. You must always set it in code, and never in the property window.

Data Type

String

LocalPort Property (AMQPClassic Control)

The TCP port in the local host where the control binds.

Syntax

amqpclassiccontrol.LocalPort[=integer]

Default Value

0

Remarks

This property must be set before a connection is attempted. It instructs the control to bind to a specific port (or communication endpoint) in the local machine.

Setting this property to 0 (default) enables the system to choose an open port at random. The chosen port will be returned by the LocalPort property after the connection is established.

LocalPort cannot be changed once a connection is made. Any attempt to set this property when a connection is active will generate an error.

This property is useful when trying to connect to services that require a trusted port in the client side.

Data Type

Integer

MessageAppId Property (AMQPClassic Control)

The Id of the application that created the message.

Syntax

amqpclassiccontrol.MessageAppId[=string]

Default Value

""

Remarks

The Id of the application that created the message.

This property holds the Id of the application that created the message. It may be empty if the message does not have an application Id set.

This value must be specified as a string no longer than 255 characters.

This property is not available at design time.

Data Type

String

MessageBody Property (AMQPClassic Control)

The message body.

Syntax

amqpclassiccontrol.MessageBody[=string]

Default Value

""

Remarks

The message body.

This property holds the body of the message. It may be empty.

To read or write binary data to the property, a Variant (Byte Array) version is provided in .MessageBodyB.

This property is not available at design time.

Data Type

Binary String

MessageChannelName Property (AMQPClassic Control)

The name of the channel the message is associated with.

Syntax

amqpclassiccontrol.MessageChannelName

Default Value

""

Remarks

The name of the channel the message is associated with.

This property reflects the name of the channel which the message is associated with; it is populated automatically by the control.

This property is read-only and not available at design time.

Data Type

String

MessageContentEncoding Property (AMQPClassic Control)

The content encoding of the message's body.

Syntax

amqpclassiccontrol.MessageContentEncoding[=string]

Default Value

""

Remarks

The content encoding of the message's body.

This property holds the content encoding of the message's body. It may be empty if the message does not have a content encoding set.

This value must be specified as a string no longer than 255 characters.

This property is not available at design time.

Data Type

String

MessageContentType Property (AMQPClassic Control)

The content type (MIME type) of the message's body.

Syntax

amqpclassiccontrol.MessageContentType[=string]

Default Value

""

Remarks

The content type (MIME type) of the message's body.

This property holds the content type (MIME type) of the message's body. It may be empty if the message does not have a content type set.

This value must be specified as a string no longer than 255 characters.

This property is not available at design time.

Data Type

String

MessageCorrelationId Property (AMQPClassic Control)

The correlation Id of the message.

Syntax

amqpclassiccontrol.MessageCorrelationId[=string]

Default Value

""

Remarks

The correlation Id of the message.

This property holds the correlation Id of the message. It may be empty if the message does not have a correlation Id set.

This value must be specified as a string no longer than 255 characters.

This property is not available at design time.

Data Type

String

MessageDeliveryMode Property (AMQPClassic Control)

The delivery mode of the message.

Syntax

amqpclassiccontrol.MessageDeliveryMode[=integer]

Default Value

0

Remarks

The delivery mode of the message.

This property holds the delivery mode of the message; possible values are:

• 0: Unspecified.
• 1: Non-persistent; the message may be lost if the server encounters an error.
• 2: Persistent; the message will not be lost, even in case of server errors.

The default is 0, which indicates that the message does not have an explicit delivery mode set.

This property is not available at design time.

Data Type

Integer

MessageExpiration Property (AMQPClassic Control)

The time-to-live value for this message.

Syntax

amqpclassiccontrol.MessageExpiration[=string]

Default Value

""

Remarks

The time-to-live value for this message.

This property specifies the time-to-live (TTL) value, in milliseconds, for this message. It may be -1 if this message does not have a TTL.

This property is not available at design time.

Data Type

String

MessageHeaders Property (AMQPClassic Control)

Headers associated with the message.

Syntax

amqpclassiccontrol.MessageHeaders[=string]

Default Value

""

Remarks

Headers associated with the message.

This property holds additional Headers associated with the message. It may be empty if the message does not have any headers set.

This property must be specified as a JSON object containing name-type-value tuples; for example:

[
  { "name": "Header1", "type": "long", "value": 12345678901234 },
  { "name": "Header2", "type": "boolean", "value": "false" },
  { "name": "Header3", "type": "string", "value": "This is a test." }
]

All "name" values must be ASCII strings that:

• Start with an ASCII letter, $, or $ character.
• Only contain ASCII letters, digits, underscores, $, and $ characters.
• Are unique among their siblings.
• Are no longer than 128 characters.

The following table describes all valid "type" values, and how to format the "value" field for each:

Note: The ulong and sstring value types are not supported when the RabbitMQCompatible configuration setting is enabled.

Headers of the table type should be specified in the same manner as shown above, while headers of the array type should be specified as a JSON array of type-value pairs; for example:

[
  { "type": "int", "value": 23 },
  { "type": "int", "value": -52 },
  { "type": "int", "value": 153325 }
]

Nesting and mixing multiple levels of arrays and tables is allowed.

This property is not available at design time.

Data Type

String

MessageId Property (AMQPClassic Control)

The unique Id of the message.

Syntax

amqpclassiccontrol.MessageId[=string]

Default Value

""

Remarks

The unique Id of the message.

This property holds the unique Id of the message. It may be empty if the message does not have a unique Id.

This value must be specified as a string no longer than 255 characters.

This property is not available at design time.

Data Type

String

MessagePriority Property (AMQPClassic Control)

The priority of the message.

Syntax

amqpclassiccontrol.MessagePriority[=integer]

Default Value

0

Remarks

The priority of the message.

This property holds the priority of the message. Valid priority values are 0-9; any other value causes the message to have unspecified priority when sent.

This property is not available at design time.

Data Type

Integer

MessageReplyTo Property (AMQPClassic Control)

The address to send replies to for the message.

Syntax

amqpclassiccontrol.MessageReplyTo[=string]

Default Value

""

Remarks

The address to send replies to for the message.

This property specifies the address to send replies to for the message. It may be empty if the message does not have a specific reply-to address set.

This value must be specified as a string no longer than 255 characters.

This property is not available at design time.

Data Type

String

MessageTimestamp Property (AMQPClassic Control)

The message's timestamp.

Syntax

amqpclassiccontrol.MessageTimestamp[=long64]

Default Value

0

Remarks

The message's timestamp.

This property holds the timestamp of the message, specified as milliseconds since the Unix epoch (January 1, 1970 00:00:00 UTC). It may be less than or equal to 0 (default) if the message does not have a timestamp set.

This property is not available at design time.

Data Type

Long64

MessageType Property (AMQPClassic Control)

The message's type.

Syntax

amqpclassiccontrol.MessageType[=string]

Default Value

""

Remarks

The message's type.

This property holds the type of the message. It may be empty if the message does not have a type set.

This value must be specified as a string no longer than 255 characters.

This property is not available at design time.

Data Type

String

MessageUserId Property (AMQPClassic Control)

The identity of the user responsible for producing the message.

Syntax

amqpclassiccontrol.MessageUserId[=string]

Default Value

""

Remarks

The identity of the user responsible for producing the message.

This property specifies the identity of the user responsible for producing the message. It may be empty if no specific user was responsible for creating the message.

A message's user Id may be used for verification or authentication by the server and/or the final consumer.

This value must be specified as a string no longer than 255 characters.

This property is not available at design time.

Data Type

String

OutgoingMessageCount Property (AMQPClassic Control)

The number of records in the OutgoingMessage arrays.

Syntax

amqpclassiccontrol.OutgoingMessageCount

Default Value

0

Remarks

This property controls the size of the following arrays:

• OutgoingMessageAppId
• OutgoingMessageBody
• OutgoingMessageChannelName
• OutgoingMessageContentEncoding
• OutgoingMessageContentType
• OutgoingMessageCorrelationId
• OutgoingMessageDeliveryMode
• OutgoingMessageExpiration
• OutgoingMessageHeaders
• OutgoingMessageId
• OutgoingMessagePriority
• OutgoingMessageReplyTo
• OutgoingMessageTimestamp
• OutgoingMessageType
• OutgoingMessageUserId

The array indices start at 0 and end at OutgoingMessageCount - 1.

This property is read-only and not available at design time.

Data Type

Integer

OutgoingMessageAppId Property (AMQPClassic Control)

The Id of the application that created the message.

Syntax

amqpclassiccontrol.OutgoingMessageAppId(OutgoingMessageIndex)

Default Value

""

Remarks

The Id of the application that created the message.

This property holds the Id of the application that created the message. It may be empty if the message does not have an application Id set.

This value must be specified as a string no longer than 255 characters.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessageBody Property (AMQPClassic Control)

The message body.

Syntax

amqpclassiccontrol.OutgoingMessageBody(OutgoingMessageIndex)

Default Value

""

Remarks

The message body.

This property holds the body of the message. It may be empty.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

To read or write binary data to the property, a Variant (Byte Array) version is provided in .OutgoingMessageBodyB.

This property is read-only and not available at design time.

Data Type

Binary String

OutgoingMessageChannelName Property (AMQPClassic Control)

The name of the channel the message is associated with.

Syntax

amqpclassiccontrol.OutgoingMessageChannelName(OutgoingMessageIndex)

Default Value

""

Remarks

The name of the channel the message is associated with.

This property reflects the name of the channel which the message is associated with; it is populated automatically by the control.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessageContentEncoding Property (AMQPClassic Control)

The content encoding of the message's body.

Syntax

amqpclassiccontrol.OutgoingMessageContentEncoding(OutgoingMessageIndex)

Default Value

""

Remarks

The content encoding of the message's body.

This property holds the content encoding of the message's body. It may be empty if the message does not have a content encoding set.

This value must be specified as a string no longer than 255 characters.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessageContentType Property (AMQPClassic Control)

The content type (MIME type) of the message's body.

Syntax

amqpclassiccontrol.OutgoingMessageContentType(OutgoingMessageIndex)

Default Value

""

Remarks

The content type (MIME type) of the message's body.

This property holds the content type (MIME type) of the message's body. It may be empty if the message does not have a content type set.

This value must be specified as a string no longer than 255 characters.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessageCorrelationId Property (AMQPClassic Control)

The correlation Id of the message.

Syntax

amqpclassiccontrol.OutgoingMessageCorrelationId(OutgoingMessageIndex)

Default Value

""

Remarks

The correlation Id of the message.

This property holds the correlation Id of the message. It may be empty if the message does not have a correlation Id set.

This value must be specified as a string no longer than 255 characters.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessageDeliveryMode Property (AMQPClassic Control)

The delivery mode of the message.

Syntax

amqpclassiccontrol.OutgoingMessageDeliveryMode(OutgoingMessageIndex)

Default Value

0

Remarks

The delivery mode of the message.

This property holds the delivery mode of the message; possible values are:

• 0: Unspecified.
• 1: Non-persistent; the message may be lost if the server encounters an error.
• 2: Persistent; the message will not be lost, even in case of server errors.

The default is 0, which indicates that the message does not have an explicit delivery mode set.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

Integer

OutgoingMessageExpiration Property (AMQPClassic Control)

The time-to-live value for this message.

Syntax

amqpclassiccontrol.OutgoingMessageExpiration(OutgoingMessageIndex)

Default Value

""

Remarks

The time-to-live value for this message.

This property specifies the time-to-live (TTL) value, in milliseconds, for this message. It may be -1 if this message does not have a TTL.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessageHeaders Property (AMQPClassic Control)

Headers associated with the message.

Syntax

amqpclassiccontrol.OutgoingMessageHeaders(OutgoingMessageIndex)

Default Value

""

Remarks

Headers associated with the message.

This property holds additional Headers associated with the message. It may be empty if the message does not have any headers set.

This property must be specified as a JSON object containing name-type-value tuples; for example:

[
  { "name": "Header1", "type": "long", "value": 12345678901234 },
  { "name": "Header2", "type": "boolean", "value": "false" },
  { "name": "Header3", "type": "string", "value": "This is a test." }
]

All "name" values must be ASCII strings that:

• Start with an ASCII letter, $, or $ character.
• Only contain ASCII letters, digits, underscores, $, and $ characters.
• Are unique among their siblings.
• Are no longer than 128 characters.

The following table describes all valid "type" values, and how to format the "value" field for each:

Note: The ulong and sstring value types are not supported when the RabbitMQCompatible configuration setting is enabled.

Headers of the table type should be specified in the same manner as shown above, while headers of the array type should be specified as a JSON array of type-value pairs; for example:

[
  { "type": "int", "value": 23 },
  { "type": "int", "value": -52 },
  { "type": "int", "value": 153325 }
]

Nesting and mixing multiple levels of arrays and tables is allowed.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessageId Property (AMQPClassic Control)

The unique Id of the message.

Syntax

amqpclassiccontrol.OutgoingMessageId(OutgoingMessageIndex)

Default Value

""

Remarks

The unique Id of the message.

This property holds the unique Id of the message. It may be empty if the message does not have a unique Id.

This value must be specified as a string no longer than 255 characters.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessagePriority Property (AMQPClassic Control)

The priority of the message.

Syntax

amqpclassiccontrol.OutgoingMessagePriority(OutgoingMessageIndex)

Default Value

0

Remarks

The priority of the message.

This property holds the priority of the message. Valid priority values are 0-9; any other value causes the message to have unspecified priority when sent.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

Integer

OutgoingMessageReplyTo Property (AMQPClassic Control)

The address to send replies to for the message.

Syntax

amqpclassiccontrol.OutgoingMessageReplyTo(OutgoingMessageIndex)

Default Value

""

Remarks

The address to send replies to for the message.

This property specifies the address to send replies to for the message. It may be empty if the message does not have a specific reply-to address set.

This value must be specified as a string no longer than 255 characters.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessageTimestamp Property (AMQPClassic Control)

The message's timestamp.

Syntax

amqpclassiccontrol.OutgoingMessageTimestamp(OutgoingMessageIndex)

Default Value

0

Remarks

The message's timestamp.

This property holds the timestamp of the message, specified as milliseconds since the Unix epoch (January 1, 1970 00:00:00 UTC). It may be less than or equal to 0 (default) if the message does not have a timestamp set.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

Long64

OutgoingMessageType Property (AMQPClassic Control)

The message's type.

Syntax

amqpclassiccontrol.OutgoingMessageType(OutgoingMessageIndex)

Default Value

""

Remarks

The message's type.

This property holds the type of the message. It may be empty if the message does not have a type set.

This value must be specified as a string no longer than 255 characters.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

OutgoingMessageUserId Property (AMQPClassic Control)

The identity of the user responsible for producing the message.

Syntax

amqpclassiccontrol.OutgoingMessageUserId(OutgoingMessageIndex)

Default Value

""

Remarks

The identity of the user responsible for producing the message.

This property specifies the identity of the user responsible for producing the message. It may be empty if no specific user was responsible for creating the message.

A message's user Id may be used for verification or authentication by the server and/or the final consumer.

This value must be specified as a string no longer than 255 characters.

The OutgoingMessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.

This property is read-only and not available at design time.

Data Type

String

Password Property (AMQPClassic Control)

A password to use for SASL authentication.

Syntax

amqpclassiccontrol.Password[=string]

Default Value

""

Remarks

This property contains a password to use for SASL authentication.

This property is not available at design time.

Data Type

String

QueueMessageCount Property (AMQPClassic Control)

The message count returned by various queue operations.

Syntax

amqpclassiccontrol.QueueMessageCount

Default Value

0

Remarks

This property is populated with a message count after calling certain queue-related methods.

This property is read-only and not available at design time.

Data Type

Integer

ReceivedMessageAppId Property (AMQPClassic Control)

The Id of the application that created the message.

Syntax

amqpclassiccontrol.ReceivedMessageAppId

Default Value

""

Remarks

The Id of the application that created the message.

This property holds the Id of the application that created the message. It may be empty if the message does not have an application Id set.

This value must be specified as a string no longer than 255 characters.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessageBody Property (AMQPClassic Control)

The message body.

Syntax

amqpclassiccontrol.ReceivedMessageBody

Default Value

""

Remarks

The message body.

This property holds the body of the message. It may be empty.

To read or write binary data to the property, a Variant (Byte Array) version is provided in .ReceivedMessageBodyB.

This property is read-only and not available at design time.

Data Type

Binary String

ReceivedMessageChannelName Property (AMQPClassic Control)

The name of the channel the message is associated with.

Syntax

amqpclassiccontrol.ReceivedMessageChannelName

Default Value

""

Remarks

The name of the channel the message is associated with.

This property reflects the name of the channel which the message is associated with; it is populated automatically by the control.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessageContentEncoding Property (AMQPClassic Control)

The content encoding of the message's body.

Syntax

amqpclassiccontrol.ReceivedMessageContentEncoding

Default Value

""

Remarks

The content encoding of the message's body.

This property holds the content encoding of the message's body. It may be empty if the message does not have a content encoding set.

This value must be specified as a string no longer than 255 characters.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessageContentType Property (AMQPClassic Control)

The content type (MIME type) of the message's body.

Syntax

amqpclassiccontrol.ReceivedMessageContentType

Default Value

""

Remarks

The content type (MIME type) of the message's body.

This property holds the content type (MIME type) of the message's body. It may be empty if the message does not have a content type set.

This value must be specified as a string no longer than 255 characters.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessageCorrelationId Property (AMQPClassic Control)

The correlation Id of the message.

Syntax

amqpclassiccontrol.ReceivedMessageCorrelationId

Default Value

""

Remarks

The correlation Id of the message.

This property holds the correlation Id of the message. It may be empty if the message does not have a correlation Id set.

This value must be specified as a string no longer than 255 characters.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessageDeliveryMode Property (AMQPClassic Control)

The delivery mode of the message.

Syntax

amqpclassiccontrol.ReceivedMessageDeliveryMode

Default Value

0

Remarks

The delivery mode of the message.

This property holds the delivery mode of the message; possible values are:

• 0: Unspecified.
• 1: Non-persistent; the message may be lost if the server encounters an error.
• 2: Persistent; the message will not be lost, even in case of server errors.

The default is 0, which indicates that the message does not have an explicit delivery mode set.

This property is read-only and not available at design time.

Data Type

Integer

ReceivedMessageExpiration Property (AMQPClassic Control)

The time-to-live value for this message.

Syntax

amqpclassiccontrol.ReceivedMessageExpiration

Default Value

""

Remarks

The time-to-live value for this message.

This property specifies the time-to-live (TTL) value, in milliseconds, for this message. It may be -1 if this message does not have a TTL.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessageHeaders Property (AMQPClassic Control)

Headers associated with the message.

Syntax

amqpclassiccontrol.ReceivedMessageHeaders

Default Value

""

Remarks

Headers associated with the message.

This property holds additional Headers associated with the message. It may be empty if the message does not have any headers set.

This property must be specified as a JSON object containing name-type-value tuples; for example:

[
  { "name": "Header1", "type": "long", "value": 12345678901234 },
  { "name": "Header2", "type": "boolean", "value": "false" },
  { "name": "Header3", "type": "string", "value": "This is a test." }
]

All "name" values must be ASCII strings that:

• Start with an ASCII letter, $, or $ character.
• Only contain ASCII letters, digits, underscores, $, and $ characters.
• Are unique among their siblings.
• Are no longer than 128 characters.

The following table describes all valid "type" values, and how to format the "value" field for each:

Note: The ulong and sstring value types are not supported when the RabbitMQCompatible configuration setting is enabled.

Headers of the table type should be specified in the same manner as shown above, while headers of the array type should be specified as a JSON array of type-value pairs; for example:

[
  { "type": "int", "value": 23 },
  { "type": "int", "value": -52 },
  { "type": "int", "value": 153325 }
]

Nesting and mixing multiple levels of arrays and tables is allowed.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessageId Property (AMQPClassic Control)

The unique Id of the message.

Syntax

amqpclassiccontrol.ReceivedMessageId

Default Value

""

Remarks

The unique Id of the message.

This property holds the unique Id of the message. It may be empty if the message does not have a unique Id.

This value must be specified as a string no longer than 255 characters.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessagePriority Property (AMQPClassic Control)

The priority of the message.

Syntax

amqpclassiccontrol.ReceivedMessagePriority

Default Value

0

Remarks

The priority of the message.

This property holds the priority of the message. Valid priority values are 0-9; any other value causes the message to have unspecified priority when sent.

This property is read-only and not available at design time.

Data Type

Integer

ReceivedMessageReplyTo Property (AMQPClassic Control)

The address to send replies to for the message.

Syntax

amqpclassiccontrol.ReceivedMessageReplyTo

Default Value

""

Remarks

The address to send replies to for the message.

This property specifies the address to send replies to for the message. It may be empty if the message does not have a specific reply-to address set.

This value must be specified as a string no longer than 255 characters.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessageTimestamp Property (AMQPClassic Control)

The message's timestamp.

Syntax

amqpclassiccontrol.ReceivedMessageTimestamp

Default Value

0

Remarks

The message's timestamp.

This property holds the timestamp of the message, specified as milliseconds since the Unix epoch (January 1, 1970 00:00:00 UTC). It may be less than or equal to 0 (default) if the message does not have a timestamp set.

This property is read-only and not available at design time.

Data Type

Long64

ReceivedMessageType Property (AMQPClassic Control)

The message's type.

Syntax

amqpclassiccontrol.ReceivedMessageType

Default Value

""

Remarks

The message's type.

This property holds the type of the message. It may be empty if the message does not have a type set.

This value must be specified as a string no longer than 255 characters.

This property is read-only and not available at design time.

Data Type

String

ReceivedMessageUserId Property (AMQPClassic Control)

The identity of the user responsible for producing the message.

Syntax

amqpclassiccontrol.ReceivedMessageUserId

Default Value

""

Remarks

The identity of the user responsible for producing the message.

This property specifies the identity of the user responsible for producing the message. It may be empty if no specific user was responsible for creating the message.

A message's user Id may be used for verification or authentication by the server and/or the final consumer.

This value must be specified as a string no longer than 255 characters.

This property is read-only and not available at design time.

Data Type

String

RemoteHost Property (AMQPClassic Control)

This property includes the address of the remote host. Domain names are resolved to IP addresses.

Syntax

amqpclassiccontrol.RemoteHost[=string]

Default Value

""

Remarks

This property specifies the IP address (IP number in dotted internet format) or the domain name of the remote host. It is set before a connection is attempted and cannot be changed once a connection is established.

If this property is set to a domain name, a DNS request is initiated, and upon successful termination of the request, this property is set to the corresponding address. If the search is not successful, an error is returned.

If the control is configured to use a SOCKS firewall, the value assigned to this property may be preceded with an "*". If this is the case, the host name is passed to the firewall unresolved and the firewall performs the DNS resolution.

Example. Connecting:

TCPClientControl.RemoteHost = "MyHostNameOrIP" TCPClientControl.RemotePort = 777 TCPClientControl.Connected = true

Data Type

String

RemotePort Property (AMQPClassic Control)

The port of the AQMP server (default is 5672). The default port for SSL is 5671.

Syntax

amqpclassiccontrol.RemotePort[=integer]

Default Value

5672

Remarks

This property specifies a service port on the remote host to connect to.

A valid port number (a value between 1 and 65535) is required for the connection to take place. The property must be set before a connection is attempted and cannot be changed once a connection is established. Any attempt to change this property while connected will fail with an error.

This property is not available at design time.

Data Type

Integer

ServerPropertyCount Property (AMQPClassic Control)

The number of records in the ServerProperty arrays.

Syntax

amqpclassiccontrol.ServerPropertyCount

Default Value

0

Remarks

This property controls the size of the following arrays:

• ServerPropertyName
• ServerPropertyValue
• ServerPropertyValueType

The array indices start at 0 and end at ServerPropertyCount - 1.

This property is read-only and not available at design time.

Data Type

Integer

ServerPropertyName Property (AMQPClassic Control)

The table property's name.

Syntax

amqpclassiccontrol.ServerPropertyName(ServerPropertyIndex)

Default Value

""

Remarks

The table field's name.

This property specifies the table field's name. The name must be an ASCII string that:

• Starts with an ASCII letter, $, or $ character.
• Only contains ASCII letters, digits, underscores, $, and $ characters.
• Is unique among all sibling table field ServerPropertyNames.
• Is no longer than 128 characters.

The ServerPropertyIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ServerPropertyCount property.

This property is read-only and not available at design time.

Data Type

String

ServerPropertyValue Property (AMQPClassic Control)

The table property's value.

Syntax

amqpclassiccontrol.ServerPropertyValue(ServerPropertyIndex)

Default Value

""

Remarks

The table field's value.

This property specifies the table field's value.

The ServerPropertyIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ServerPropertyCount property.

This property is read-only and not available at design time.

Data Type

String

ServerPropertyValueType Property (AMQPClassic Control)

The table property's value type.

Syntax

amqpclassiccontrol.ServerPropertyValueType(ServerPropertyIndex)

Possible Values

fvtBoolean(0), 
fvtByte(1), 
fvtUbyte(2), 
fvtShort(3), 
fvtUshort(4), 
fvtInt(5), 
fvtUint(6), 
fvtLong(7), 
fvtUlong(8), 
fvtFloat(9), 
fvtDouble(10), 
fvtDecimal(11), 
fvtSstring(12), 
fvtString(13), 
fvtArray(14), 
fvtTimestamp(15), 
fvtTable(16), 
fvtNull(17)

Default Value

17

Remarks

The table field's value type.

This property specifies the table field's value type (and thus, the format of the data in the ServerPropertyValue property). Acceptable value types are:

Note: The fvtUlong (8) and fvtSstring (12) value types are not supported when the RabbitMQCompatible configuration setting is enabled.

For the fvtArray (14) value type, the ServerPropertyValue should be specified as a JSON array of type-value pairs; for example:

[
  { "type": "int", "value": 23 },
  { "type": "int", "value": -52 },
  { "type": "int", "value": 153325 }
]

For the fvtTable (16) value type, the ServerPropertyValue should be specified as a JSON object containing name-type-value tuples; for example:

{
  { "name": "Test1", "type": "long", "value": 12345678901234 },
  { "name": "Test2", "type": "boolean", "value": "false" },
  { "name": "Test3", "type": "string", "value": "This is a test." }
}

Notes regarding fvtArray (14) and fvtTable (16) type ServerPropertyValues:

• All "type" fields in the JSON content must be set to one of the value types in the table above.
• For fvtTable (16) type ServerPropertyValues, all "name" fields must adhere to the rules described by the ServerPropertyKey documentation.
• Nesting and mixing multiple levels of arrays and tables in the JSON is allowed.

The ServerPropertyIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ServerPropertyCount property.

This property is read-only and not available at design time.

Data Type

Integer

SSLAcceptServerCertEncoded Property (AMQPClassic Control)

This is the certificate (PEM/Base64 encoded).

Syntax

amqpclassiccontrol.SSLAcceptServerCertEncoded[=string]

Default Value

""

Remarks

This is the certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The SSLAcceptServerCertStore and SSLAcceptServerCertSubject properties also may be used to specify a certificate.

When SSLAcceptServerCertEncoded is set, a search is initiated in the current SSLAcceptServerCertStore for the private key of the certificate. If the key is found, SSLAcceptServerCertSubject is updated to reflect the full subject of the selected certificate; otherwise, SSLAcceptServerCertSubject is set to an empty string.

To read or write binary data to the property, a Variant (Byte Array) version is provided in .SSLAcceptServerCertEncodedB.

This property is not available at design time.

Data Type

Binary String

SSLCertEncoded Property (AMQPClassic Control)

This is the certificate (PEM/Base64 encoded).

Syntax

amqpclassiccontrol.SSLCertEncoded[=string]

Default Value

""

Remarks

This is the certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The SSLCertStore and SSLCertSubject properties also may be used to specify a certificate.

When SSLCertEncoded is set, a search is initiated in the current SSLCertStore for the private key of the certificate. If the key is found, SSLCertSubject is updated to reflect the full subject of the selected certificate; otherwise, SSLCertSubject is set to an empty string.

To read or write binary data to the property, a Variant (Byte Array) version is provided in .SSLCertEncodedB.

This property is not available at design time.

Data Type

Binary String

SSLCertStore Property (AMQPClassic Control)

This is the name of the certificate store for the client certificate.

Syntax

amqpclassiccontrol.SSLCertStore[=string]

Default Value

"MY"

Remarks

This is the name of the certificate store for the client certificate.

The SSLCertStoreType property denotes the type of the certificate store specified by SSLCertStore. If the store is password protected, specify the password in SSLCertStorePassword.

SSLCertStore is used in conjunction with the SSLCertSubject property to specify client certificates. If SSLCertStore has a value, and SSLCertSubject or SSLCertEncoded is set, a search for a certificate is initiated. Please see the SSLCertSubject property for details.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:

When the certificate store type is PFXFile, this property must be set to the name of the file. When the type is PFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

To read or write binary data to the property, a Variant (Byte Array) version is provided in .SSLCertStoreB.

Data Type

Binary String

SSLCertStorePassword Property (AMQPClassic Control)

If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store.

Syntax

amqpclassiccontrol.SSLCertStorePassword[=string]

Default Value

""

Remarks

If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store.

Data Type

String

SSLCertStoreType Property (AMQPClassic Control)

This is the type of certificate store for this certificate.

Syntax

amqpclassiccontrol.SSLCertStoreType[=integer]

Possible Values

cstUser(0), 
cstMachine(1), 
cstPFXFile(2), 
cstPFXBlob(3), 
cstJKSFile(4), 
cstJKSBlob(5), 
cstPEMKeyFile(6), 
cstPEMKeyBlob(7), 
cstPublicKeyFile(8), 
cstPublicKeyBlob(9), 
cstSSHPublicKeyBlob(10), 
cstP7BFile(11), 
cstP7BBlob(12), 
cstSSHPublicKeyFile(13), 
cstPPKFile(14), 
cstPPKBlob(15), 
cstXMLFile(16), 
cstXMLBlob(17), 
cstJWKFile(18), 
cstJWKBlob(19), 
cstSecurityKey(20), 
cstBCFKSFile(21), 
cstBCFKSBlob(22), 
cstPKCS11(23), 
cstAuto(99)

Default Value

0

Remarks

This is the type of certificate store for this certificate.

The control supports both public and private keys in a variety of formats. When the cstAuto value is used, the control will automatically determine the type. This property can take one of the following values:

Data Type

Integer

SSLCertSubject Property (AMQPClassic Control)

This is the subject of the certificate used for client authentication.

Syntax

amqpclassiccontrol.SSLCertSubject[=string]

Default Value

""

Remarks

This is the subject of the certificate used for client authentication.

This property must be set after all other certificate properties are set. When this property is set, a search is performed in the current certificate store to locate a certificate with a matching subject.

If a matching certificate is found, the property is set to the full subject of the matching certificate.

If an exact match is not found, the store is searched for subjects containing the value of the property.

If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks a random certificate in the certificate store.

The certificate subject is a comma-separated list of distinguished name fields and values. For instance, "CN=www.server.com, OU=test, C=US, E=support@nsoftware.com". Common fields and their meanings are as follows:

If a field value contains a comma, it must be quoted.

Data Type

String

SSLEnabled Property (AMQPClassic Control)

Whether TLS/SSL is enabled.

Syntax

amqpclassiccontrol.SSLEnabled[=boolean]

Default Value

False

Remarks

This setting specifies whether TLS/SSL is enabled in the control. When False (default) the control operates in plaintext mode. When True TLS/SSL is enabled.

TLS/SSL may also be enabled by setting SSLStartMode. Setting SSLStartMode will automatically update this property value.

If the default port (5672) is selected when SSLEnabled is set to true, the port will automatically be changed to the default port for AMQP with SSL (5671). Likewise, if port 5671 is selected when SSLEnabled is set to false, the port will automatically be changed to the default port. If the port has been set to any value other than the default values, it will remain the same when the value of SSLEnabled changes.

This property is not available at design time.

Data Type

Boolean

SSLProvider Property (AMQPClassic Control)

This specifies the SSL/TLS implementation to use.

Syntax

amqpclassiccontrol.SSLProvider[=integer]

Possible Values

sslpAutomatic(0), 
sslpPlatform(1), 
sslpInternal(2)

Default Value

0

Remarks

This property specifies the SSL/TLS implementation to use. In most cases the default value of 0 (Automatic) is recommended and should not be changed. When set to 0 (Automatic) the control will select whether to use the platform implementation or the internal implementation depending on the operating system as well as the TLS version being used.

Possible values are:

In most cases using the default value (Automatic) is recommended. The control will select a provider depending on the current platform.

When Automatic is selected the platform implementation is used by default. When TLS 1.3 is enabled via SSLEnabledProtocols the internal implementation is used.

Data Type

Integer

SSLServerCertEncoded Property (AMQPClassic Control)

This is the certificate (PEM/Base64 encoded).

Syntax

amqpclassiccontrol.SSLServerCertEncoded

Default Value

""

Remarks

This is the certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The SSLServerCertStore and SSLServerCertSubject properties also may be used to specify a certificate.

When SSLServerCertEncoded is set, a search is initiated in the current SSLServerCertStore for the private key of the certificate. If the key is found, SSLServerCertSubject is updated to reflect the full subject of the selected certificate; otherwise, SSLServerCertSubject is set to an empty string.

To read or write binary data to the property, a Variant (Byte Array) version is provided in .SSLServerCertEncodedB.

This property is read-only and not available at design time.

Data Type

Binary String

Timeout Property (AMQPClassic Control)

A timeout for the control.

Syntax

amqpclassiccontrol.Timeout[=integer]

Default Value

60

Remarks

If the Timeout property is set to 0, all operations return immediately, potentially failing with a WOULDBLOCK error if data cannot be sent immediately.

If Timeout is set to a positive value, data is sent in a blocking manner and the control will wait for the operation to complete before returning control. The control will handle any potential WOULDBLOCK errors internally and automatically retry the operation for a maximum of Timeout seconds.

The control will use DoEvents to enter an efficient wait loop during any potential waiting period, making sure that all system events are processed immediately as they arrive. This ensures that the host application does not "freeze" and remains responsive.

If Timeout expires, and the operation is not yet complete, the control fails with an error.

Please note that by default, all timeouts are inactivity timeouts, i.e. the timeout period is extended by Timeout seconds when any amount of data is successfully sent or received.

The default value for the Timeout property is 60 seconds.

Data Type

Integer

User Property (AMQPClassic Control)

A username to use for SASL authentication.

Syntax

amqpclassiccontrol.User[=string]

Default Value

""

Remarks

This property contains a username to use for SASL authentication.

This property is not available at design time.

Data Type

String

VirtualHost Property (AMQPClassic Control)

The virtual host to connect to.

Syntax

amqpclassiccontrol.VirtualHost[=string]

Default Value

"/"

Remarks

This property specifies the virtual host to connect to on the server, and is set to / by default.

Note that the configuration of the server defines what virtual hosts are available.

This setting cannot be changed while connected.

This property is not available at design time.

Data Type

String

BindQueue Method (AMQPClassic Control)

Binds a queue to an exchange.

Syntax

amqpclassiccontrol.BindQueue ChannelName, QueueName, ExchangeName, RoutingKey, NoWait

Remarks

This method is used to bind the queue named QueueName to the exchange named ExchangeName. Exchanges use bindings to determine which queues to route messages to.

Multiple bindings between the same queue and exchange with different RoutingKeys and/or arguments are allowed; requests that would create a duplicate binding are ignored. No queue will ever receive duplicate copies of any message, regardless of what bindings are present on the server.

Note that all AMQP 0.9.1 servers automatically bind all queues to their default exchange (which is always a direct exchange with no name) using each queue's name as the binding's routing key. This makes it easy to send a message to a specific queue without having to declare bindings; just call PublishMessage, pass empty string for ExchangeName, and the name of the desired queue for RoutingKey.

ChannelName controls what channel the control will send the request over. While any channel can technically be used, keep in mind that the server will close it if a channel error occurs. For this reason, it is good practice to make requests such as this one using a channel that is not involved in message publishing or consumption.

QueueName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters.

The server's default exchange may be specified by passing empty string for ExchangeName. Otherwise, ExchangeName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters.

The RoutingKey parameter specifies the binding's routing key. Exchanges that use routing-key-based logic make some sort of comparison between the routing keys of incoming messages and this value to decide which messages should be forwarded to the specified queue. Examples of exchange types which use routing keys include:

• direct exchanges, which compare (for equality) the routing keys of incoming messages to the routing keys of each queue bound to them.
• topic exchanges, which match the routing keys of incoming messages against the routing pattern of each queue bound to them.

Not all exchange types make use of routing keys, in which case empty string can be passed for the RoutingKey parameter. Examples of exchange types which don't use routing keys include:

• fanout exchanges simply forward incoming messages to all queues bound to them, unconditionally.
• header exchanges only forward messages that include certain headers. When binding a queue to a header exchange, add items to the Argument* properties to describe the headers that eligible messages must have, and whether they must have any or all of those headers.

Note that the format of the RoutingKey parameter and/or the content of the Argument* properties may differ slightly between server implementations. Refer to your server's documentation to determine what it expects to receive for each exchange type that it supports.

The NoWait parameter, if True, will cause the server to execute the request asynchronously. For asynchronous request handling, the server only sends back a response in case of an error.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because:

• No queue with the given QueueName exists.
• No exchange with the given ExchangeName exists.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Binding a Queue to an Exchange // Bind a queue to an exchange. Messages will only be delivered to the queue if their routing key is "MyRoutingKey". amqpc1.BindQueue("channel", "MyQueue", "MyExchange", "MyRoutingKey", false);

CancelConsume Method (AMQPClassic Control)

Cancels an existing consumer.

Syntax

amqpclassiccontrol.CancelConsume ChannelName, ConsumerTag, NoWait

Remarks

This method requests that the server cancel the consumer identified by the given ConsumerTag on the channel specified by ChannelName.

The NoWait parameter, if True, will cause the server to execute the request asynchronously. For asynchronous request handling, the server only sends back a response in case of an error.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because no consumer with the given ConsumerTag exists.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

CloseChannel Method (AMQPClassic Control)

Closes a channel.

Syntax

amqpclassiccontrol.CloseChannel ChannelName

Remarks

This method closes the channel named ChannelName and removes it from the Channel* properties.

If no channel with the given ChannelName exists, an exception will be thrown.

CommitTransaction Method (AMQPClassic Control)

Commits the current transaction for a channel.

Syntax

amqpclassiccontrol.CommitTransaction ChannelName

Remarks

This method commits the current transaction for the channel with the given ChannelName. A new transaction is started immediately after the current one is committed.

Refer to EnableTransactionMode for more information about transactions.

An exception is thrown if a channel with the given ChannelName doesn't exist, or if the server returns an error because the channel does not have transaction mode enabled.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Config Method (AMQPClassic Control)

Sets or retrieves a configuration setting.

Syntax

amqpclassiccontrol.Config ConfigurationString

Remarks

Config is a generic method available in every control. It is used to set and retrieve configuration settings for the control.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the control, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

Connect Method (AMQPClassic Control)

This method connects to a remote host.

Syntax

amqpclassiccontrol.Connect 

Remarks

This method connects to the remote host specified by RemoteHost and RemotePort. For instance: component.RemoteHost = "MyHostNameOrIP"; component.RemotePort = 7777; component.Connect();

ConnectTo Method (AMQPClassic Control)

This method connects to a remote host.

Syntax

amqpclassiccontrol.ConnectTo Host, Port

Remarks

This method connects to the remote host specified by the Host and Port parameters. For instance: component.ConnectTo("MyHostNameOrIP", 777)

Consume Method (AMQPClassic Control)

Starts a new consumer for a given queue.

Syntax

amqpclassiccontrol.Consume ChannelName, QueueName, ConsumerTag, NoLocal, NoAck, Exclusive, NoWait

Remarks

This method instructs the server to start a new consumer on the queue named QueueName; once the consumer is created, it will cause messages enqueued to the specified queue to be delivered to the control over the channel specified by ChannelName.

Consumers last as long as the channel they were created on, or until they are cancelled using the CancelConsume method. Each time a message is delivered to the control, it is immediately added to the IncomingMessage* properties, the ReceivedMessage* properties are populated, and the MessageIn event fires.

ConsumerTag is a string which uniquely identifies the new consumer on the specified channel. If empty string is passed for ConsumerTag, the server will generate a consumer tag automatically when it creates the . this auto-generated consumer tag can then be retrieved by querying the ConsumerTag configuration setting after this method returns.

The NoLocal parameter, if True, ensures that the consumer never consumes messages published on the same channel. (Note that this functionality is not available on RabbitMQ servers, which ignore the NoLocal parameter).

The NoAck parameter controls whether the server will expect the control to acknowledge the each message delivered. Refer to MessageIn for more information about acknowledging messages.

The Exclusive parameter, if True, will cause the control to request that the server create an exclusive consumer. Attaching an exclusive consumer to a queue prevents any other consumers from consuming messages from that queue.

The NoWait parameter, if True, will cause the server to execute the request asynchronously. For asynchronous request handling, the server only sends back a response in case of an error.

Additional arguments may be sent with this request by adding them to the Argument* properties. Arguments are server-dependent; refer to your server's documentation to determine if any additional arguments apply for this request.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because:

• No queue with the given QueueName exists.
• The given ConsumerTag is already in use on the specified channel.
• An exclusive consumer was requested for a queue which already has consumers attached to it.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Receiving a Message // MessageIn event handler. amqpc1.OnMessageIn += (s, e) => { if (e.MessageCount == -1) { // The server pushed a message to us asynchronously due to a consumer we created. Console.WriteLine("The server pushed this message to us via consumer '" + e.ConsumerTag + "':"); Console.WriteLine(amqpc1.ReceivedMessage.Body); } else if (e.DeliveryTag > 0) { // We pulled a message from a queue with the FetchMessage() method. Console.WriteLine("Message successfully pulled:"); Console.WriteLine(amqpc1.ReceivedMessage.Body); Console.WriteLine(e.MessageCount + " messages are still available to pull."); } else { // We tried to pull a message, but there were none available to pull. Console.WriteLine("No messages available to pull."); } }; // Attach a consumer to "MyQueue". amqpc1.Consume("channel", "MyQueue", "consumerTag", false, true, false, false); // Or, try to fetch a message from "MyQueue". amqpc1.FetchMessage("channel", "MyQueue", true);

CreateChannel Method (AMQPClassic Control)

Creates a new channel.

Syntax

amqpclassiccontrol.CreateChannel ChannelName

Remarks

This method creates a new channel with the name ChannelName and adds it to the Channel* properties. If a channel with the given ChannelName already exists, an error will be thrown.

Connecting and Creating a Channel // The examples in this documentation use a RabbitMQ server, which requires SASL Plain auth. amqpc1.AuthScheme = AmqpclassicAuthSchemes.smSASLPlain; amqpc1.User = "guest"; amqpc1.Password = "guest"; amqpc1.SSLEnabled = true; amqpc1.ConnectTo("amqpclassic.test-server.com", 5671); amqpc1.CreateChannel("channel");

DeclareExchange Method (AMQPClassic Control)

Verifies that an exchange exists, potentially creating it if necessary.

Syntax

amqpclassiccontrol.DeclareExchange ChannelName, ExchangeName, ExchangeType, Passive, Durable, AutoDelete, NoWait

Remarks

This method is used to verify that an exchange named ExchangeName exists; and potentially creates it if no such exchange exists.

ChannelName controls what channel the control will send the request over. While any channel can technically be used, keep in mind that the server will close it if a channel error occurs. For this reason, it is good practice to make requests such as this one using a channel that is not involved in message publishing or consumption.

ExchangeName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters, and must not begin with amq. unless the Passive parameter is True.

ExchangeType specifies the exchange type. All servers support the direct and fanout exchange types, and most should also support the topic and header exchange types. Some servers may support additional, custom exchange types as well. Refer to your server's documentation for more information about each exchange type, and to determine what exchange types it supports other than direct and fanout.

If Passive is True, the server will only verify that an exchange with the given ExchangeName actually exists (regardless of how it is configured).

If Passive is False, and no exchange named ExchangeName currently exists, the server will create one.

If Passive is False, and there is a preexisting exchange named ExchangeName, the server will verify that its current configuration matches the given parameters and arguments.

Durable specifies what happens to the exchange in the event of a server restart. Durable exchanges will be recreated, while non-durable (transient) exchanges will not.

AutoDelete specifies whether the server should automatically delete the exchange when all queues have been unbound from it. Note that this parameter is only sent if the RabbitMQCompatible configuration setting is enabled; it is ignored otherwise.

The NoWait parameter, if True, will cause the server to execute the request asynchronously. For asynchronous request handling, the server only sends back a response in case of an error.

Additional arguments may be sent with this request by adding them to the Argument* properties. Arguments are server-dependent; refer to your server's documentation to determine if any additional arguments apply for this request.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because:

• One of the parameter constraints described above was violated.
• One of the verification cases described above fails.
• The value passed for ExchangeType did not correspond to an exchange type supported by the server.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Declaring an Exchange // Declare a direct-type exchange. amqpc1.DeclareExchange("channel", "MyExchange", "direct", false, false, false, false);

DeclareQueue Method (AMQPClassic Control)

Verifies that a queue exists, potentially creating it if necessary.

Syntax

amqpclassiccontrol.DeclareQueue ChannelName, QueueName, Passive, Durable, Exclusive, AutoDelete, NoWait

Remarks

This method is used to verify that a queue named QueueName exists; and potentially creates it if no such queue exists.

After each successful call to this method, the control populates the QueueMessageCount property, as well as the QueueConsumerCount and QueueName configuration settings. Refer to each one for more information.

ChannelName controls what channel the control will send the request over. While any channel can technically be used, keep in mind that the server will close it if a channel error occurs. For this reason, it is good practice to make requests such as this one using a channel that is not involved in message publishing or consumption.

If creating a new queue, empty string can be passed for QueueName to have the server automatically generate a name for the new queue (which can then be retrieved using the QueueName configuration setting). In all other cases, QueueName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters, and must not begin with amq. unless the Passive parameter is True.

If Passive is True, the server will only verify that a queue with the given QueueName actually exists (regardless of how it is configured).

If Passive is False, and no queue named QueueName currently exists, the server will create one.

If Passive is False, and there is a preexisting queue named QueueName, the server will verify that its current configuration matches the given parameters and arguments.

Durable specifies what happens to the queue in the event of a server restart. Durable queue will be recreated, while non-durable (transient) queue will not. (Note that the messages in durable queues will still be lost unless they are marked as persistent.)

Exclusive, if True, indicates that the queue may only be accessed by the current connection. Exclusive queues are deleted when the current connection closes.

AutoDelete specifies whether the server should automatically delete the queue when all consumers have finished using it. (Note that auto-delete queues aren't eligible for deletion until after a consumer attaches to them for the first time.)

The NoWait parameter, if True, will cause the server to execute the request asynchronously. For asynchronous request handling, the server only sends back a response in case of an error.

Additional arguments may be sent with this request by adding them to the Argument* properties. Arguments are server-dependent; refer to your server's documentation to determine if any additional arguments apply for this request.

An exception is thrown if no channel with the given ChannelName exists, if QueueName empty string and NoWait is True, or if the server returns an error because:

• One of the parameter constraints described above was violated.
• One of the verification cases described above fails.
• An attempt was made to verify (i.e., the Passive parameter was True) another connection's exclusive queue.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Declaring a Queue // Declare a queue. amqpc1.DeclareQueue("channel", "MyQueue", false, false, false, false, false);

DeleteExchange Method (AMQPClassic Control)

Deletes an exchange.

Syntax

amqpclassiccontrol.DeleteExchange ChannelName, ExchangeName, IfUnused, NoWait

Remarks

This method is used to delete an exchange.

ChannelName controls what channel the control will send the request over. While any channel can technically be used, keep in mind that the server will close it if a channel error occurs. For this reason, it is good practice to make requests such as this one using a channel that is not involved in message publishing or consumption.

ExchangeName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters, and must not begin with amq..

When IfUnused is True, the server will only delete the exchange if no queues are bound to it.

The NoWait parameter, if True, will cause the server to execute the request asynchronously. For asynchronous request handling, the server only sends back a response in case of an error.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because:

• The value passed for ExchangeName fails one or more of the constraints described above.
• No exchange named ExchangeName exists. (This does not apply for RabbitMQ; attempting to delete a non-existent exchange will always succeed.)
• The IfUnused parameter was True, but the exchange still had one or more queues bound to it.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

DeleteQueue Method (AMQPClassic Control)

Deletes a queue.

Syntax

amqpclassiccontrol.DeleteQueue ChannelName, QueueName, IfUnused, IfEmpty, NoWait

Remarks

This method is used to delete the queue named QueueName.

After each successful call to this method, the control populates the QueueMessageCount property with the number of messages deleted along with the queue. (Note that this does not occur if the NoWait parameter is set to True.)

ChannelName controls what channel the control will send the request over. While any channel can technically be used, keep in mind that the server will close it if a channel error occurs. For this reason, it is good practice to make requests such as this one using a channel that is not involved in message publishing or consumption.

QueueName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters, and must not begin with amq..

When IfUnused is True, the server will only delete the queue if no consumers are attached to it.

When IfEmpty is True, the server will only delete the queue if it has no messages in it. (When IfEmpty is False, servers will typically move any remaining messages to a dead-letter queue, if one is available.)

The NoWait parameter, if True, will cause the server to execute the request asynchronously. For asynchronous request handling, the server only sends back a response in case of an error.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because:

• The value passed for QueueName fails one or more of the constraints described above.
• No queue named QueueName exists. (This does not apply for RabbitMQ; attempting to delete a non-existent queue will always succeed.)
• The IfUnused parameter was True, but the queue still had one or more consumers attached to it.
• The IfEmpty parameter was True, but the queue still had one or more messages in it.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Disconnect Method (AMQPClassic Control)

This method disconnects from the remote host.

Syntax

amqpclassiccontrol.Disconnect 

Remarks

This method disconnects from the remote host. Calling this method is equivalent to setting the Connected property to False.

DoEvents Method (AMQPClassic Control)

Processes events from the internal message queue.

Syntax

amqpclassiccontrol.DoEvents 

Remarks

When DoEvents is called, the control processes any available events. If no events are available, it waits for a preset period of time, and then returns.

EnablePublishConfirms Method (AMQPClassic Control)

Enables publish confirmations mode for a channel.

Syntax

amqpclassiccontrol.EnablePublishConfirms ChannelName, NoWait

Remarks

This method enables publish confirmations mode for the channel with the given ChannelName.

While a channel is in publish confirmations mode, the server will acknowledge each message published by the control. The control will wait to fire the MessageOut event until it receives this acknowledgement. (Note that this mode is only available when the RabbitMQCompatible configuration setting is enabled.)

Note that a channel will stay in publish confirmations mode, once enabled, until it is deleted.

The NoWait parameter, if True, will cause the server to execute the request asynchronously. For asynchronous request handling, the server only sends back a response in case of an error.

An exception is thrown if the RabbitMQCompatible configuration setting is currently False, if no channel with the given ChannelName exists, or if EnableTransactionMode has been called for the specified channel previously.

EnableTransactionMode Method (AMQPClassic Control)

Enables transaction mode for a channel.

Syntax

amqpclassiccontrol.EnableTransactionMode ChannelName

Remarks

This method enables transaction mode for the channel with the given ChannelName.

While a channel is in transaction mode, all messages published and acknowledgements sent over it will be part of a transaction, and the server will wait to process them until the transaction is either committed or rolled back.

To commit the current transaction on a channel, call CommitTransaction; and to roll it back (and discard the messages and acknowledgements that were part of it), call RollbackTransaction.

Keep in mind that, according to the AMQP 0.9.1 specification:

• A new transaction is always started immediately after committing or rolling back the current one, which means that...
• ...a channel will stay in transaction mode, once enabled, until it is deleted.
• Transactions are only guaranteed to be atomic if all messages published and acknowledgements sent affect a single queue.
• Any messages published on a channel in transaction mode that have the Mandatory or Immediate flags set are not guaranteed to be included in the transaction.

An exception is thrown if no channel with the given ChannelName exists, or if EnablePublishConfirms has been called for the specified channel previously.

FetchMessage Method (AMQPClassic Control)

Attempts to fetch a message from a given queue.

Syntax

amqpclassiccontrol.FetchMessage ChannelName, QueueName, NoAck

Remarks

This method attempts to fetch a message from the queue named QueueName over the channel named ChannelName.

If a message is fetched as a result of this method being called, it is immediately added to the IncomingMessage* properties, the ReceivedMessage* properties are populated, and the MessageIn event fires.

Even if no message gets fetched, the MessageIn event will still fire as long as the request was successful. The server returns the number of available messages in the specified queue in response to all successful fetch requests, and that count is exposed by MessageIn event's MessageCount parameter. Refer to the MessageIn event for more information.

QueueName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters.

The NoAck parameter controls whether the server will expect the control to acknowledge the fetched message. Refer to MessageIn for more information about acknowledging messages.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because:

• No queue with the given QueueName exists.
• The specified queue exists, but is locked or otherwise unavailable to consume from (e.g., an exclusive consumer might be attached to it).

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Receiving a Message // MessageIn event handler. amqpc1.OnMessageIn += (s, e) => { if (e.MessageCount == -1) { // The server pushed a message to us asynchronously due to a consumer we created. Console.WriteLine("The server pushed this message to us via consumer '" + e.ConsumerTag + "':"); Console.WriteLine(amqpc1.ReceivedMessage.Body); } else if (e.DeliveryTag > 0) { // We pulled a message from a queue with the FetchMessage() method. Console.WriteLine("Message successfully pulled:"); Console.WriteLine(amqpc1.ReceivedMessage.Body); Console.WriteLine(e.MessageCount + " messages are still available to pull."); } else { // We tried to pull a message, but there were none available to pull. Console.WriteLine("No messages available to pull."); } }; // Attach a consumer to "MyQueue". amqpc1.Consume("channel", "MyQueue", "consumerTag", false, true, false, false); // Or, try to fetch a message from "MyQueue". amqpc1.FetchMessage("channel", "MyQueue", true);

Interrupt Method (AMQPClassic Control)

Interrupt the current action and disconnects from the remote host.

Syntax

amqpclassiccontrol.Interrupt 

Remarks

This method will interrupt the current method (if applicable) and cause the control to disconnect from the remote host.

PublishMessage Method (AMQPClassic Control)

Publishes a message.

Syntax

amqpclassiccontrol.PublishMessage ChannelName, ExchangeName, RoutingKey, Mandatory, Immediate

Remarks

This method is used to publish the message specified by the Message* properties to the exchange named ExchangeName over the channel specified by ChannelName.

When this method is called, the message to publish is immediately added to the OutgoingMessage* properties, and the MessageOut event fires once it has been sent (or, if the specified channel is in "publish confirmations" mode, after the server has acknowledged it).

Note that all AMQP 0.9.1 servers automatically bind all queues to their default exchange (which is always a direct exchange with no name) using each queue's name as the binding's routing key. This makes it easy to send a message to a specific queue without having to declare bindings; just call PublishMessage, pass empty string for ExchangeName, and the name of the desired queue for RoutingKey.

Note that messages published over channels which are in either transaction or "publish confirmations" mode may be handled differently than they would be on a channel in normal mode. Refer to the EnableTransactionMode and EnablePublishConfirms methods for more information about what each mode entails.

The server's default exchange may be specified by passing empty string for ExchangeName. Otherwise, ExchangeName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters.

The RoutingKey parameter specifies the message's routing key. Whether this parameter needs to be non-empty, and what format it should have if so, depends on the type of exchange it is being sent to. Some exchange types may use information included with the message, such as its MessageHeaders. Refer to BindQueue for more information about how routing keys are used, and to your server's documentation for information on what it expects.

The Mandatory parameter controls what the server should do if the message can't be routed to any queue (either because it isn't eligible for any of the queues bound to the specified exchange because of how their bindings are configured, or because no queues are bound to the exchange in the first place). If True, the server will return the message, at which point the MessageReturned event will be fired. If False, the server will drop the message.

The Immediate parameter controls what the server should do if the message can't be immediately delivered to any consumer (either because it cannot be routed to a queue, or because the queues it can be routed to have no active consumers attached to them). If True, the server will return the message, at which point the MessageReturned event will be fired. If False, the server will queue the message if possible, or drop it if not.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because:

• The value passed for ExchangeName fails one or more of the constraints described above.
• No exchange named ExchangeName exists.
• The message is rejected for some reason.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Publishing a Message amqpc1.Message.Body = "Hello, world!"; // Publish a message to the server's default (no-name) exchange, using the name of a specific queue as the routing key. amqpc1.PublishMessage("channel", "", "MyQueue", false, false); // Publish a message to the "MyExchange" exchange, using the routing key "MyRoutingKey". amqpc1.PublishMessage("channel", "MyExchange", "MyRoutingKey", false, false);

PurgeQueue Method (AMQPClassic Control)

Purges all messages from a queue.

Syntax

amqpclassiccontrol.PurgeQueue ChannelName, QueueName, NoWait

Remarks

This method purges all messages from the queue named QueueName. Messages which have been sent but are awaiting acknowledgement are not affected.

After each successful call to this method, the control populates the QueueMessageCount property with the number of messages purged from the queue. (Note that this does not occur if the NoWait parameter is set to True.)

ChannelName controls what channel the control will send the request over. While any channel can technically be used, keep in mind that the server will close it if a channel error occurs. For this reason, it is good practice to make requests such as this one using a channel that is not involved in message publishing or consumption.

QueueName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters.

The NoWait parameter, if True, will cause the server to execute the request asynchronously. For asynchronous request handling, the server only sends back a response in case of an error.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because no queue named QueueName exists.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Recover Method (AMQPClassic Control)

Request that the server redeliver all messages on a given channel that have not been acknowledged.

Syntax

amqpclassiccontrol.Recover ChannelName, Requeue

Remarks

This method is used to request that the server redeliver all messages that it previously sent to the control on the channel specified by ChannelName which are still awaiting acknowledgement.

A call to this method may cause the server to redeliver zero or more messages over the channel specified by ChannelName. Those messages will cause the MessageIn event to fire with its Redelivered event parameter set to True.

The Requeue parameter controls how the server should attempt to redeliver the messages awaiting acknowledgement. If set to True, the server will simple put the messages back on their original queues, and they will be delivered like any other queued messages (potentially to other consumers). If set to False, the server will redeliver the messages to the control directly.

An exception is thrown if no channel with the given ChannelName exists, or (for RabbitMQ only) if the server returns an error because Requeue was False. (RabbitMQ only supports setting Requeue to True.)

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

Reset Method (AMQPClassic Control)

Reset the control.

Syntax

amqpclassiccontrol.Reset 

Remarks

This method will reset the control's properties to their default values.

ResetMessage Method (AMQPClassic Control)

Resets the Message properties.

Syntax

amqpclassiccontrol.ResetMessage 

Remarks

This method resets the Message* properties.

RollbackTransaction Method (AMQPClassic Control)

Rolls back the current transaction for a channel.

Syntax

amqpclassiccontrol.RollbackTransaction ChannelName

Remarks

This method rolls back the current transaction for the channel with the given ChannelName. A new transaction is started immediately after the current one is rolled back.

Refer to EnableTransactionMode for more information about transactions.

An exception is thrown if a channel with the given ChannelName doesn't exist, or if the server returns an error because the channel does not have transaction mode enabled.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

SetChannelAccept Method (AMQPClassic Control)

Disables or enables message acceptance for a given channel.

Syntax

amqpclassiccontrol.SetChannelAccept ChannelName, Accept

Remarks

This method is used to disable and enable message acceptance for the channel specified by ChannelName.

A channel is always configured to accept messages when first created, allowing the server to freely deliver messages to the control for any consumers that have been created on that channel using the Consume method.

Disabling message acceptance for a channel prevents the server from automatically delivering messages to the control over it; however, it is still possible to use the FetchMessage method to synchronously attempt to retrieve a message on a channel with message acceptance disabled.

An exception is thrown if no channel with the given ChannelName exists, or (for RabbitMQ only) if the server returns an error because Accept was False. (RabbitMQ does not support disabling message acceptance.)

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

SetQoS Method (AMQPClassic Control)

Requests a specific quality of service (QoS).

Syntax

amqpclassiccontrol.SetQoS ChannelName, PrefetchSize, PrefetchCount, Global

Remarks

This method is used to request a specific quality of service for a certain scope. When the PrefetchSize and/or PrefetchCount are set for a certain scope, the server will limit how many messages it sends to the control before stopping to wait for or or more of them to be acknowledged.

ChannelName is the name of the channel which is used to send the request. Depending on the server and what Global is set to, it may also be significant to the request itself (refer to the Global parameter's description, below, for more information).

PrefetchSize specifies a window size in bytes; i.e., the server will stop sending messages if the total size of all of the currently unacknowledged messages already sent, plus the size of the next message that could be sent, exceeds PrefetchSize bytes. A PrefetchSize of 0 indicates no limit. (Note that RabbitMQ does not support prefetch size limits.)

PrefetchCount specifies the number of unacknowledged messages the server will limit itself to sending. A PrefetchCount of 0 indicates no limit.

Global specifies the scope which the QoS request should apply to. It is interpreted differently based on whether the server is RabbitMQ or not. Refer to this table:

Keep the following things in mind when using QoS:

• The limits specified by a QoS request only affect messages that require acknowledgement.
• How the server chooses to handle interactions between QoS settings at different scopes is server-dependent.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error for any reason.

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

UnbindQueue Method (AMQPClassic Control)

Removes a previously-created queue binding.

Syntax

amqpclassiccontrol.UnbindQueue ChannelName, QueueName, ExchangeName, RoutingKey

Remarks

This method removes a previously-created queue binding.

ChannelName controls what channel the control will send the request over. While any channel can technically be used, keep in mind that the server will close it if a channel error occurs. For this reason, it is good practice to make requests such as this one using a channel that is not involved in message publishing or consumption.

QueueName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters.

The server's default exchange may be specified by passing empty string for ExchangeName. Otherwise, ExchangeName must be a non-empty string consisting only of letters, digits, hyphens, underscores, periods, and colons. It must be no longer than 255 characters.

RoutingKey should be the same routing key used when originally creating the binding that is to be removed. For bindings created using arguments instead of a routing key, the Argument* properties must contain the same items used originally instead.

An exception is thrown if no channel with the given ChannelName exists, or if the server returns an error because:

• No queue with the given QueueName exists. (Does not apply to RabbitMQ.)
• No exchange with the given ExchangeName exists. (Does not apply to RabbitMQ.)

Note that in AMQP, server errors are grouped into "connection errors" and "channel errors", and both are fatal. That is, if the server returns a channel error, it will then close the channel which caused the error; and if it returns a connection error, it will then close the connection. The AMQPClassic control's Error Codes page includes AMQP's various connection and channel errors.

ChannelReadyToSend Event (AMQPClassic Control)

Fires when a channel is ready to send messages.

Syntax

Sub amqpclassiccontrol_ChannelReadyToSend(ChannelName As String)

Remarks

This event fires when a channel is ready to send messages.

ChannelName is the name of the channel.

Connected Event (AMQPClassic Control)

This event is fired immediately after a connection completes (or fails).

Syntax

Sub amqpclassiccontrol_Connected(StatusCode As Integer, Description As String)

Remarks

If the connection is made normally, StatusCode is 0 and Description is "OK".

If the connection fails, StatusCode has the error code returned by the Transmission Control Protocol (TCP)/IP stack. Description contains a description of this code. The value of StatusCode is equal to the value of the error. The corresponding Visual Basic error code can be obtained by adding 15001 to this value.

Please refer to the Error Codes section for more information.

ConnectionStatus Event (AMQPClassic Control)

This event is fired to indicate changes in the connection state.

Syntax

Sub amqpclassiccontrol_ConnectionStatus(ConnectionEvent As String, StatusCode As Integer, Description As String)

Remarks

The ConnectionStatus event is fired when the connection state changes: for example, completion of a firewall or proxy connection or completion of a security handshake.

The ConnectionEvent parameter indicates the type of connection event. Values may include the following:

Disconnected Event (AMQPClassic Control)

This event is fired when a connection is closed.

Syntax

Sub amqpclassiccontrol_Disconnected(StatusCode As Integer, Description As String)

Remarks

If the connection is broken normally, StatusCode is 0 and Description is "OK".

If the connection is broken for any other reason, StatusCode has the error code returned by the Transmission Control Protocol (TCP/IP) subsystem. Description contains a description of this code. The value of StatusCode is equal to the value of the TCP/IP error. The corresponding Visual Basic error code can be obtained by adding 15001 to this value.

Please refer to the Error Codes section for more information.

Error Event (AMQPClassic Control)

Fired when information is available about errors during data delivery.

Syntax

Sub amqpclassiccontrol_Error(ErrorCode As Integer, Description As String)

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the control fails with an error.

The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

Log Event (AMQPClassic Control)

Fires once for each log message.

Syntax

Sub amqpclassiccontrol_Log(LogLevel As Integer, Message As String, LogType As String)

Remarks

This event fires once for each log message generated by the control. The verbosity is controlled by the LogLevel setting.

LogLevel indicates the level of the Message. Possible values are:

LogType identifies the type of log entry. Possible values are:

• Info: General information about the control.
• Frame: Frame status messages.

MessageIn Event (AMQPClassic Control)

Fires when a message is received; as well as when an attempt is made to fetch a message from a currently empty queue.

Syntax

Sub amqpclassiccontrol_MessageIn(ChannelName As String, ConsumerTag As String, DeliveryTag As Long64, Redelivered As Boolean, ExchangeName As String, RoutingKey As String, MessageCount As Integer, Accept As Integer)

Remarks

This event fires anytime a message is received. There are two possible ways for the control to receive a message:

• Messages can be asynchronously pushed to the control from the server. At any point in time, the server may push a message to the control from a queue that the Consume method has been used to attach a consumer to.
• Messages can be synchronously pulled from the server by the control. The FetchMessage method is used to attempt to pull (or "fetch") messages from a specific queue.

This event also fires anytime FetchMessage is called against a queue that currently has no messages available to pull. This is a special case, and results in only the ChannelName and MessageCount event parameters being populated.

Other than that special case, and any exceptions noted below, this event's parameters are populated the same way regardless of the manner in which messages are received.

ChannelName always reflects the name of the associated channel.

ConsumerTag reflects the consumer tag associated with the consumer that caused the server to push the message to the control. (ConsumerTag is always empty for messages pulled from the server by FetchMessage since no consumers are involved.)

DeliveryTag reflects the server-assigned, channel-specific delivery tag number for the incoming message.

Redelivered reflects whether the server is redelivering a message that is has delivered previously.

ExchangeName reflects the name of the exchange to which the incoming message was originally published. (If the message was originally published to the server's default exchange, whose name is always the empty string, ExchangeName will also be empty.)

RoutingKey reflects the routing key that the message was originally published with.

MessageCount is always -1 when this event fires due to a message being pushed to the control by the server. When this event fires as a result of FetchMessage being called, MessageCount reflects the number of messages still available in the queue the control tried to pull a message from (even if there were no messages available to pull).

The Accept parameter can be set to control how the control responds to the incoming message, if it needs to be acknowledged (if the message doesn't need to be acknowledged, the value set to the Accept parameter is ignored). Valid values are:

• 0 - default: Accept the message; send a positive acknowledgement.
• 1: Silently accept the message; don't send any acknowledgement.
• 2: Accept the message; send a cumulative positive acknowledgement coving this, and all previously unacknowledged, messages.
• 3: Reject the message; send a negative acknowledgement for it, and instruct the server not to return it to the queue.
• 4: Reject the message; send a negative acknowledgement for it, and instruct the server to return it to the queue.

If the value provided for the Accept parameter isn't one of those described above, the default (0) will be used instead.

Receiving a Message // MessageIn event handler. amqpc1.OnMessageIn += (s, e) => { if (e.MessageCount == -1) { // The server pushed a message to us asynchronously due to a consumer we created. Console.WriteLine("The server pushed this message to us via consumer '" + e.ConsumerTag + "':"); Console.WriteLine(amqpc1.ReceivedMessage.Body); } else if (e.DeliveryTag > 0) { // We pulled a message from a queue with the FetchMessage() method. Console.WriteLine("Message successfully pulled:"); Console.WriteLine(amqpc1.ReceivedMessage.Body); Console.WriteLine(e.MessageCount + " messages are still available to pull."); } else { // We tried to pull a message, but there were none available to pull. Console.WriteLine("No messages available to pull."); } }; // Attach a consumer to "MyQueue". amqpc1.Consume("channel", "MyQueue", "consumerTag", false, true, false, false); // Or, try to fetch a message from "MyQueue". amqpc1.FetchMessage("channel", "MyQueue", true);

MessageOut Event (AMQPClassic Control)

Fires when a message is published.

Syntax

Sub amqpclassiccontrol_MessageOut(ChannelName As String, ExchangeName As String, RoutingKey As String, MessageId As String, DeliveryTag As Long64, Accepted As Boolean)

Remarks

This event fires anytime a message is published; or after an outgoing message has been acknowledged by the server, if the channel it was published on is in "publish confirmations" mode.

ChannelName reflects the name of the channel the message was published on.

ExchangeName reflects the name of the exchange the message was published to. (If the message was published to the server's default exchange, whose name is always the empty string, ExchangeName will also be empty.)

RoutingKey reflects the routing key that the message was published with.

MessageId reflects the message's unique Id, if one was set.

DeliveryTag reflects the channel-specific delivery tag number for the message. (Note that this is only populated for messages published on a channel in "publish confirmations" mode; otherwise it will be set to -1.)

Accepted indicates whether the server published back a positive True or negative False acknowledgement for the outgoing message. Note that this is only valid for messages published on a channel in "publish confirmations" mode; Accepted will always be True messages published on a channel in normal or transaction mode.

Refer to EnablePublishConfirms for more information about channels in "publish confirmations" mode.

MessageReturned Event (AMQPClassic Control)

Fires if a previously published message is returned by the server due to it being undeliverable.

Syntax

Sub amqpclassiccontrol_MessageReturned(ChannelName As String, ReplyCode As Integer, ReplyText As String, ExchangeName As String, RoutingKey As String)

Remarks

This event fires if the server returns a previously published message because it could not deliver it. Typically, messages are only undeliverable in one of the following situations:

• The message was originally published with the Mandatory option enabled, but there were no queues it could be routed to.
• The message was originally published with the Immediate option enabled, but there were no consumers it could be delivered to immediately on any queue it was routed to (or there were no queues it could be routed to).

The ReceivedMessage* properties will be populated with the returned message.

ChannelName reflects the name of the channel the message was originally published on.

ReplyCode will be an AMQP error code that indicates the reason why the message was returned. (Tip: The AMQPClassic control's Error Codes page includes the various AMQP error codes.)

ReplyText will be a message with further details about why the message was returned.

ExchangeName reflects the name of the exchange to which the message was originally published. (If the message was originally published to the server's default exchange, whose name is always the empty string, ExchangeName will also be empty.)

RoutingKey reflects the routing key that the message was originally published with.

SSLServerAuthentication Event (AMQPClassic Control)

Fired after the server presents its certificate to the client.

Syntax

Sub amqpclassiccontrol_SSLServerAuthentication(CertEncoded As String, CertSubject As String, CertIssuer As String, Status As String, Accept As Boolean)

Remarks

During this event, the client can decide whether or not to continue with the connection process. The Accept parameter is a recommendation on whether to continue or close the connection. This is just a suggestion: application software must use its own logic to determine whether or not to continue.

When Accept is False, Status shows why the verification failed (otherwise, Status contains the string OK). If it is decided to continue, you can override and accept the certificate by setting the Accept parameter to True.

SSLStatus Event (AMQPClassic Control)

Fired when secure connection progress messages are available.

Syntax

Sub amqpclassiccontrol_SSLStatus(Message As String)

Remarks

The event is fired for informational and logging purposes only. This event tracks the progress of the connection.

Config Settings (AMQPClassic Control)

AMQPClassic Config Settings

TCPClient Config Settings

SSL Config Settings

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
..
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
..
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

Socket Config Settings

Trappable Errors (AMQPClassic Control)

AMQPClassic Errors

TCPClient Errors

SSL Errors

TCP/IP Errors