WSServer Class

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The WSServer class is used to create a WebSocket server.

Syntax

class ipworks.WSServer

Remarks

The WSServer class functions as a server that facilitates incoming WebSocket connections and offers a convenient means of transmitting and receiving data over the established connections.

To start, the local_port property must be specified to a valid port. This port will be used to accept incoming connections. Then, call the start_listening method to start listening on the specified port. The WSServer class supports both plaintext and Secure Sockets Layer/Transport Layer Security (SSL/TLS) connections. The SSLStatus event provides information about the SSL handshake. Additional SSL related settings are also supported via the Config method. The SSLCert properties are used to select a certificate for the server. Note: A valid certificate MUST be selected before the server can function.

Upon a client's connection, the on_web_socket_open_request event will be fired. To accept the connection, simply allow the event to complete its execution. Conversely, to reject the request, the StatusCode parameter can be set to an appropriate HTTP error code, such as 401.

By default, each instance of WSServer has the capacity to handle up to 1,000 simultaneous incoming connections. You can change the maximum number of simultaneous connections by adjusting the MaxConnections configuration setting. This setting allows you to increase the limit up to 100,000 or decrease it to a lower value based on your needs.

Each connection is identified by a unique ConnectionId, an identifier generated by the component to distinguish individual connections. The ConnectionId is also included as a parameter in WSServer's events to identify the associated connection.

After receiving a connection, incoming data can be accessed through the DataIn event. To transmit data to a client, the send, send_text, or send_file methods can be employed, or the ws_connection_data_to_send field can be set accordingly.

Note: Server components are designed to process events as they occur. To ensure that events are processed in a timely manner, do_events should be called in a loop after the server is started.

Property List

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

Method List

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

Event List

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

Config Settings

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

connection_backlog Property

This property includes the maximum number of pending connections maintained by the Transmission Control Protocol (TCP)/IP subsystem.

Syntax

def get_connection_backlog() -> int: ...
def set_connection_backlog(value: int) -> None: ...

connection_backlog = property(get_connection_backlog, set_connection_backlog)

Default Value

5

Remarks

This property contains the maximum number of pending connections maintained by the TCP/IP subsystem. This value reflects the SOMAXCONN option for the main listening socket. The default value for most systems is 5. You may set this property to a larger value if the server is expected to receive a large number of connections, and queuing them is desirable.

ws_connection_count Property

The number of records in the WSConnection arrays.

Syntax

def get_ws_connection_count() -> int: ...

ws_connection_count = property(get_ws_connection_count, None)

Default Value

0

Remarks

This property controls the size of the following arrays:

• ws_connection_accept_data
• ws_connection_bytes_sent
• ws_connection_connected
• ws_connection_connection_id
• ws_connection_data_format
• ws_connection_data_to_send
• ws_connection_host
• ws_connection_line_mode
• ws_connection_local_address
• ws_connection_origin
• ws_connection_ready_to_send
• ws_connection_remote_host
• ws_connection_remote_port
• ws_connection_request_headers
• ws_connection_request_uri
• ws_connection_sub_protocols
• ws_connection_timeout

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

This property is read-only.

ws_connection_accept_data Property

Setting this property to false temporarily disables data reception (and the DataIn event) for the connection.

Syntax

def get_ws_connection_accept_data(connection_id: int) -> bool: ...
def set_ws_connection_accept_data(connection_id: int, value: bool) -> None: ...

Default Value

TRUE

Remarks

Setting this property to false temporarily disables data reception (and the on_data_in event) for the connection. Setting this to true re-enables data reception.

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

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

ws_connection_bytes_sent Property

This property shows how many bytes were sent after the last assignment to DataToSend .

Syntax

def get_ws_connection_bytes_sent(connection_id: int) -> int: ...

Default Value

0

Remarks

This property shows how many bytes were sent after the last assignment to ws_connection_data_to_send. Please check ws_connection_data_to_send for more information.

Note: This property will always return 0 when the class is operating in the synchronous mode (i.e., the ws_connection_timeout property is set to a positive value).

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_connected Property

This property is used to disconnect individual connections and/or show their status.

Syntax

def get_ws_connection_connected(connection_id: int) -> bool: ...
def set_ws_connection_connected(connection_id: int, value: bool) -> None: ...

Default Value

FALSE

Remarks

This property is used to disconnect individual connections and/or show their status.

The ws_connection_connected property may be set to false to close the connection.

ws_connection_connected also shows the status of a particular connection (connected/disconnected).

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

ws_connection_connection_id Property

This property contains an identifier generated by the class to identify each connection.

Syntax

def get_ws_connection_connection_id(connection_id: int) -> str: ...

Default Value

""

Remarks

This property contains an identifier generated by the class to identify each connection. This identifier is unique to this connection.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_data_format Property

The format of the data being sent.

Syntax

def get_ws_connection_data_format(connection_id: int) -> int: ...
def set_ws_connection_data_format(connection_id: int, value: int) -> None: ...

Default Value

0

Remarks

The format of the data being sent. When data is sent over an established connection it is either considered as text or binary data. Text data is UTF-8 encoded. Binary data has no encoding associated with it.

Possible values are:

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

ws_connection_data_to_send Property

This property contains a string of data to be sent to the remote host.

Syntax

def set_ws_connection_data_to_send(connection_id: int, value: bytes) -> None: ...

Default Value

""

Remarks

This property contains a string of data to be sent to the remote host. Write-only property.

Assigning a string to the ws_connection_data_to_send makes the class send the string to the remote host. The send method provides similar functionality.

If you are sending data to the remote host faster than it can process it, or faster than the network's bandwidth allows, the outgoing queue might fill up. When this happens, the operation fails with error 10035: "[10035] Operation would block" (WSAEWOULDBLOCK). You can check this error, and then try to send the data again. . The bytes_sent property shows how many bytes were sent (if any). If 0 bytes were sent, then you can wait for the on_ready_to_send event before attempting to send data again.

Note: The on_ready_to_send event is not fired when part of the data is sent successfully.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is write-only.

ws_connection_host Property

The Host header value of the connected client.

Syntax

def get_ws_connection_host(connection_id: int) -> str: ...

Default Value

""

Remarks

The Host header value of the connected client.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_line_mode Property

When LineMode is false (default), the class will fire the DataIn event once for each message received from the server.

Syntax

def get_ws_connection_line_mode(connection_id: int) -> bool: ...

Default Value

FALSE

Remarks

When ws_connection_line_mode is false (default), the component will fire the on_data_in event once for each message received from the server. When line_mode is True, the component will instead fire on_data_in for each line of data received. The maximum length of a line can be controlled by the MaxLineLength configuration setting.

Note: This property is read-only, and should be set through the change_line_mode method.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_local_address Property

This property shows the IP address of the interface through which the connection is passing.

Syntax

def get_ws_connection_local_address(connection_id: int) -> str: ...

Default Value

""

Remarks

This property shows the IP address of the interface through which the connection is passing.

ws_connection_local_address is important for multihomed hosts so that it can be used to find the particular network interface through which an individual connection is going.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_origin Property

The Origin header value of the connected client.

Syntax

def get_ws_connection_origin(connection_id: int) -> str: ...

Default Value

""

Remarks

The Origin header value of the connected client.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_ready_to_send Property

This indicates whether the class is ready to send data.

Syntax

def get_ws_connection_ready_to_send(connection_id: int) -> bool: ...

Default Value

FALSE

Remarks

This indicates whether the class is ready to send data.

This property indicates that the underlying TCP/IP subsystem is ready to accept data. This is True after a client connects but will become False after a failed ws_connection_data_to_send.

After a failed ws_connection_data_to_send, the on_ready_to_send event will fire and this property will be True when data can be sent again.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_remote_host Property

This property shows the IP address of the connected client.

Syntax

def get_ws_connection_remote_host(connection_id: int) -> str: ...

Default Value

""

Remarks

This property shows the IP address of the connected client.

The connection must be valid or an error will be fired.

If the class 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.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_remote_port Property

This property shows the port of the connected client.

Syntax

def get_ws_connection_remote_port(connection_id: int) -> int: ...

Default Value

0

Remarks

This property shows the port of the connected client.

The connection must be valid or an error will be fired.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_request_headers Property

The HTTP headers sent by the client in the initial WebSocket connection request.

Syntax

def get_ws_connection_request_headers(connection_id: int) -> str: ...

Default Value

""

Remarks

The HTTP headers sent by the client in the initial WebSocket connection request.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_request_uri Property

The requested URI sent by the client in the initial WebSocket connection request.

Syntax

def get_ws_connection_request_uri(connection_id: int) -> str: ...

Default Value

""

Remarks

The requested URI sent by the client in the initial WebSocket connection request.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_sub_protocols Property

The subprotocols (application-level protocols layered over the WebSocket Protocol) sent by the client in the initial WebSocket connection request.

Syntax

def get_ws_connection_sub_protocols(connection_id: int) -> str: ...

Default Value

""

Remarks

The subprotocols (application-level protocols layered over the WebSocket Protocol) sent by the client in the initial WebSocket connection request.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

This property is read-only.

ws_connection_timeout Property

This property specifies a timeout for the class.

Syntax

def get_ws_connection_timeout(connection_id: int) -> int: ...
def set_ws_connection_timeout(connection_id: int, value: int) -> None: ...

Default Value

0

Remarks

This property specifies a timeout for the class.

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

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

The class will use do_events 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 class 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 ws_connection_timeout property is 0 (asynchronous operation).

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the ws_connection_count property.

default_timeout Property

An initial timeout value to be used by incoming connections.

Syntax

def get_default_timeout() -> int: ...
def set_default_timeout(value: int) -> None: ...

default_timeout = property(get_default_timeout, set_default_timeout)

Default Value

0

Remarks

This property is used by the class to set the operational timeout value of all inbound connections once they are established.

By default, the timeout is 0, meaning that all inbound connections will behave asynchronously.

listening Property

If set to True, the class accepts incoming connections on LocalPort.

Syntax

def get_listening() -> bool: ...
def set_listening(value: bool) -> None: ...

listening = property(get_listening, set_listening)

Default Value

FALSE

Remarks

This property indicates whether the class is listening for connections on the port specified by the local_port property.

Note: Use the start_listening and stop_listening methods to control whether the class is listening.

local_host Property

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

Syntax

def get_local_host() -> str: ...
def set_local_host(value: str) -> None: ...

local_host = property(get_local_host, set_local_host)

Default Value

""

Remarks

The local_host 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 class initiate connections (or accept in the case of server classs) only through that interface.

If the class is connected, the local_host 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: local_host is not persistent. You must always set it in code, and never in the property window.

local_port Property

This property includes the Transmission Control Protocol (TCP) port in the local host where the class listens.

Syntax

def get_local_port() -> int: ...
def set_local_port(value: int) -> None: ...

local_port = property(get_local_port, set_local_port)

Default Value

0

Remarks

This property must be set before the class can start listening. If its value is 0, then the TCP/IP subsystem picks a port number at random. The port number can be found by checking the value of this property after the class is listening (i.e., after successfully assigning True to the listening property).

The service port is not shared among servers so two classs cannot be listening on the same port at the same time.

ssl_authenticate_clients Property

If set to True, the server asks the client(s) for a certificate.

Syntax

def get_ssl_authenticate_clients() -> bool: ...
def set_ssl_authenticate_clients(value: bool) -> None: ...

ssl_authenticate_clients = property(get_ssl_authenticate_clients, set_ssl_authenticate_clients)

Default Value

FALSE

Remarks

This property is used in conjunction with the on_ssl_client_authentication event. Please refer to the documentation of the on_ssl_client_authentication event for details.

ssl_cert_encoded Property

This is the certificate (PEM/Base64 encoded).

Syntax

def get_ssl_cert_encoded() -> bytes: ...
def set_ssl_cert_encoded(value: bytes) -> None: ...

ssl_cert_encoded = property(get_ssl_cert_encoded, set_ssl_cert_encoded)

Default Value

""

Remarks

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

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

ssl_cert_store Property

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

Syntax

def get_ssl_cert_store() -> bytes: ...
def set_ssl_cert_store(value: bytes) -> None: ...

ssl_cert_store = property(get_ssl_cert_store, set_ssl_cert_store)

Default Value

"MY"

Remarks

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

The ssl_cert_store_type property denotes the type of the certificate store specified by ssl_cert_store. If the store is password protected, specify the password in ssl_cert_store_password.

ssl_cert_store is used in conjunction with the ssl_cert_subject property to specify client certificates. If ssl_cert_store has a value, and ssl_cert_subject or ssl_cert_encoded is set, a search for a certificate is initiated. Please see the ssl_cert_subject 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).

ssl_cert_store_password Property

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

Syntax

def get_ssl_cert_store_password() -> str: ...
def set_ssl_cert_store_password(value: str) -> None: ...

ssl_cert_store_password = property(get_ssl_cert_store_password, set_ssl_cert_store_password)

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.

ssl_cert_store_type Property

This is the type of certificate store for this certificate.

Syntax

def get_ssl_cert_store_type() -> int: ...
def set_ssl_cert_store_type(value: int) -> None: ...

ssl_cert_store_type = property(get_ssl_cert_store_type, set_ssl_cert_store_type)

Default Value

0

Remarks

This is the type of certificate store for this certificate.

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

ssl_cert_subject Property

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

Syntax

def get_ssl_cert_subject() -> str: ...
def set_ssl_cert_subject(value: str) -> None: ...

ssl_cert_subject = property(get_ssl_cert_subject, set_ssl_cert_subject)

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.

use_ssl Property

Determines if SSL is negotiated with incoming connections.

Syntax

def get_use_ssl() -> bool: ...
def set_use_ssl(value: bool) -> None: ...

use_ssl = property(get_use_ssl, set_use_ssl)

Default Value

FALSE

Remarks

When set to True the class will attempt to negotiate SSL with all connecting clients. To enable SSL support you must supply a valid certificate via the ssl_cert_store_type, ssl_cert_store, ssl_cert_store_password, and ssl_cert_subject properties

The default value is False.

change_line_mode Method

Controls whether the class will fire DataIn when an EOL is received for the specified connection.

Syntax

def change_line_mode(connection_id: int, line_mode: bool) -> None: ...

Remarks

When ws_connection_line_mode is set to false (default), the component will fire the on_data_in event once for each message received from the client. When LineMode is set to True, the component will instead fire on_data_in for each line of data received. The maximum length of a line can be controlled by the MaxLineLength[ConnectionId]; configuration setting.

Note: This method is offered as a convenience feature, and has no effect on the behavior of the WebSocket protocol.

config Method

Sets or retrieves a configuration setting.

Syntax

def config(configuration_string: str) -> str: ...

Remarks

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

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, 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.

disconnect Method

This method disconnects the specified client.

Syntax

def disconnect(connection_id: int) -> None: ...

Remarks

Calling this method will disconnect the client specified by the ConnectionId parameter.

do_events Method

Processes events from the internal message queue.

Syntax

def do_events() -> None: ...

Remarks

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

interrupt Method

Interrupts a synchronous send to the remote host.

Syntax

def interrupt(connection_id: int) -> None: ...

Remarks

This property is called using the Connection ID if you wish to interrupt a connection and stop a file from uploading without disconnecting the client connected to the class. If you use send_file to upload a file, the class will run synchronously on that Connection ID until it is completed.

ping Method

Sends a Ping request to the remote host.

Syntax

def ping(connection_id: int) -> None: ...

Remarks

This method sends a Ping request to the remote host and waits for a corresponding Pong response.

The timeout property specifies how long to wait for the Pong response.

send Method

Sends binary data to the client.

Syntax

def send(connection_id: int, data: bytes) -> None: ...

Remarks

This method sends the binary data specified by Data to the client specified by ConnectionId.

send_bytes Method

This method sends binary data to the specified client.

Syntax

def send_bytes(connection_id: int, data: bytes) -> None: ...

Remarks

This method sends binary data to the client identified by ConnectionId. To send text, use the send_text method instead.

When ws_connection_timeout is set to 0, the class will behave asynchronously. If you are sending data to the remote host faster than it can process it, or faster than the network's bandwidth allows, the outgoing queue might fill up. When this happens, the operation fails with error 10035: "[10035] Operation would block" (WSAEWOULDBLOCK). You can check this error, and then try to send the data again. . The bytes_sent property shows how many bytes were sent (if any). If 0 bytes were sent, then you can wait for the on_ready_to_send event before attempting to send data again.

Note: The on_ready_to_send event is not fired when part of the data is sent successfully.

This method sends binary data to the client identified by ConnectionId. To send text, use the send_text method instead.

When ws_connection_timeout is set to 0, the class will behave asynchronously. If you are sending data to the remote host faster than it can process it, or faster than the network's bandwidth allows, the outgoing queue might fill up. When this happens, the operation fails with error 10035: "[10035] Operation would block" (WSAEWOULDBLOCK). You can check this error, and then try to send the data again. . The bytes_sent property shows how many bytes were sent (if any). If 0 bytes were sent, then you can wait for the on_ready_to_send event before attempting to send data again.

Note: The on_ready_to_send event is not fired when part of the data is sent successfully.

send_file Method

This method sends the file to the remote host.

Syntax

def send_file(connection_id: int, file_name: str) -> None: ...

Remarks

This method sends the file to the client specified by the ConnectionId.

send_text Method

Sends text data to the client.

Syntax

def send_text(connection_id: int, text: str) -> None: ...

Remarks

This method sends text to the client identified by ConnectionId. To send binary data, use the send_bytes method instead.

When ws_connection_timeout is set to 0, the class will behave asynchronously. If you are sending data to the remote host faster than it can process it, or faster than the network's bandwidth allows, the outgoing queue might fill up. When this happens, the operation fails with error 10035: "[10035] Operation would block" (WSAEWOULDBLOCK). You can check this error, and then try to send the data again. . The bytes_sent property shows how many bytes were sent (if any). If 0 bytes were sent, then you can wait for the on_ready_to_send event before attempting to send data again.

Note: The on_ready_to_send event is not fired when part of the data is sent successfully.

This method sends text to the client identified by ConnectionId. Data sent with this method will always be treated as text data regardless of the value of ws_connection_data_format. The class will UTF-8 encode the supplied text.

shutdown Method

This method shuts down the server.

Syntax

def shutdown() -> None: ...

Remarks

This method shuts down the server. Calling this method is equivalent to calling stop_listening and then breaking every client connection by calling disconnect.

start_listening Method

This method starts listening for incoming connections.

Syntax

def start_listening() -> None: ...

Remarks

This method begins listening for incoming connections on the port specified by local_port. Once listening, events will fire as new clients connect and data are transferred.

To stop listening for new connections, call stop_listening. To stop listening for new connections and to disconnect all existing clients, call shutdown.

stop_listening Method

This method stops listening for new connections.

Syntax

def stop_listening() -> None: ...

Remarks

This method stops listening for new connections. After being called, any new connection attempts will be rejected. Calling this method does not disconnect existing connections.

To stop listening and to disconnect all existing clients, call shutdown instead.

on_connected Event

Fired when a WebSocket is successfully opened.

Syntax

class WSServerConnectedEventParams(object):
  @property
  def connection_id() -> int: ...

# In class WSServer:
@property
def on_connected() -> Callable[[WSServerConnectedEventParams], None]: ...
@on_connected.setter
def on_connected(event_hook: Callable[[WSServerConnectedEventParams], None]) -> None: ...

Remarks

The on_connected event is fired when a WebSocket is successfully opened on a connection.

ConnectionId identifies the connection.

on_connection_request Event

This event is fired when a request for connection comes from a remote host.

Syntax

class WSServerConnectionRequestEventParams(object):
  @property
  def address() -> str: ...

  @property
  def port() -> int: ...

  @property
  def accept() -> bool: ...
  @accept.setter
  def accept(value) -> None: ...

# In class WSServer:
@property
def on_connection_request() -> Callable[[WSServerConnectionRequestEventParams], None]: ...
@on_connection_request.setter
def on_connection_request(event_hook: Callable[[WSServerConnectionRequestEventParams], None]) -> None: ...

Remarks

This event indicates an incoming connection. The connection is accepted by default. Address and Port will contain information about the remote host requesting the inbound connection. If you want to refuse it, you can set the Accept parameter to False.

on_data_in Event

Fired when data is received.

Syntax

class WSServerDataInEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def data_format() -> int: ...

  @property
  def text() -> bytes: ...

  @property
  def eom() -> bool: ...

  @property
  def eol() -> bool: ...

# In class WSServer:
@property
def on_data_in() -> Callable[[WSServerDataInEventParams], None]: ...
@on_data_in.setter
def on_data_in(event_hook: Callable[[WSServerDataInEventParams], None]) -> None: ...

Remarks

The on_data_in event provides the data received from the client identified by the ConnectionId parameter.

The incoming data is provided through the Text parameter.

The DataFormat parameter identifies the encoding (if any) of the data. Possible value are:

The EOM parameter stands for End Of Message. By default the class will fire the on_data_in event as data is received. Larger messages will be fragmented and will cause the event to fire multiple times. When EOM is true within the event this indicates the current fragment is also the final fragment of the message. The class may also be configured to buffer the message internally until the complete message is received. To enable this set BufferMessage to true.

The EOL parameter stands for End of Line. When line_mode is false, EOL will always be false. When line_mode is true, EOL will be True if the on_data_in event fired because an EOL was received, and false if the on_data_in event fired because MaxLineLength was reached.

on_disconnected Event

Fired when a WebSocket connection is disconnected.

Syntax

class WSServerDisconnectedEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def status_code() -> int: ...

  @property
  def description() -> str: ...

# In class WSServer:
@property
def on_disconnected() -> Callable[[WSServerDisconnectedEventParams], None]: ...
@on_disconnected.setter
def on_disconnected(event_hook: Callable[[WSServerDisconnectedEventParams], None]) -> None: ...

Remarks

When the connection is closed the StatusCode parameter may be used to determine if the disconnect occurred normally or if there was an error condition. If the connection is closed normally the StatusCode will be 1000. The Description parameter will contain a textual description returned by the server. Common StatusCode values are:

on_error Event

Information about errors during data delivery.

Syntax

class WSServerErrorEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def error_code() -> int: ...

  @property
  def description() -> str: ...

# In class WSServer:
@property
def on_error() -> Callable[[WSServerErrorEventParams], None]: ...
@on_error.setter
def on_error(event_hook: Callable[[WSServerErrorEventParams], None]) -> None: ...

Remarks

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

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

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

on_log Event

Fires once for each log message.

Syntax

class WSServerLogEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def log_level() -> int: ...

  @property
  def message() -> str: ...

  @property
  def log_type() -> str: ...

# In class WSServer:
@property
def on_log() -> Callable[[WSServerLogEventParams], None]: ...
@on_log.setter
def on_log(event_hook: Callable[[WSServerLogEventParams], None]) -> None: ...

Remarks

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

LogLevel indicates the level of message. Possible values are:

The value 1 (Info) logs basic information including the URL, HTTP version, and connection status details.

The value 2 (Verbose) logs additional information about the initial HTTP request.

The value 3 (Debug) logs additional debug information (if available).

Message is the log entry.

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

• "Info"
• "Error"
• "Verbose"
• "Debug"

on_ping Event

Fired when a ping request or response is received.

Syntax

class WSServerPingEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def payload() -> bytes: ...

  @property
  def response() -> bool: ...

# In class WSServer:
@property
def on_ping() -> Callable[[WSServerPingEventParams], None]: ...
@on_ping.setter
def on_ping(event_hook: Callable[[WSServerPingEventParams], None]) -> None: ...

Remarks

This event fires when a ping request or response is received from the client identified by the ConnectionId parameter. This event is informational only. When the class receives a ping request it will automatically reply with a pong.

Payload holds the payload of the request, if any.

Response is True if the incoming packet is a ping response. If the incoming packet is a ping request this is False.

on_ready_to_send Event

This event is fired when the class is ready to send data.

Syntax

class WSServerReadyToSendEventParams(object):
  @property
  def connection_id() -> int: ...

# In class WSServer:
@property
def on_ready_to_send() -> Callable[[WSServerReadyToSendEventParams], None]: ...
@on_ready_to_send.setter
def on_ready_to_send(event_hook: Callable[[WSServerReadyToSendEventParams], None]) -> None: ...

Remarks

The on_ready_to_send event indicates that the underlying Transmission Control Protocol (TCP)/IP subsystem is ready to accept data after a failed data_to_send. This event is also fired immediately after a connection is established.

on_ssl_client_authentication Event

This event is fired when the client presents its credentials to the server.

Syntax

class WSServerSSLClientAuthenticationEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def cert_encoded() -> bytes: ...

  @property
  def cert_subject() -> str: ...

  @property
  def cert_issuer() -> str: ...

  @property
  def status() -> str: ...

  @property
  def accept() -> bool: ...
  @accept.setter
  def accept(value) -> None: ...

# In class WSServer:
@property
def on_ssl_client_authentication() -> Callable[[WSServerSSLClientAuthenticationEventParams], None]: ...
@on_ssl_client_authentication.setter
def on_ssl_client_authentication(event_hook: Callable[[WSServerSSLClientAuthenticationEventParams], None]) -> None: ...

Remarks

This event enables the server to decide whether or not to continue. The Accept parameter is a recommendation on whether to continue or to 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").

on_ssl_connection_request Event

This event fires when a Secure Sockets Layer (SSL) connection is requested.

Syntax

class WSServerSSLConnectionRequestEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def supported_cipher_suites() -> str: ...

  @property
  def supported_signature_algs() -> str: ...

  @property
  def cert_store_type() -> int: ...
  @cert_store_type.setter
  def cert_store_type(value) -> None: ...

  @property
  def cert_store() -> str: ...
  @cert_store.setter
  def cert_store(value) -> None: ...

  @property
  def cert_password() -> str: ...
  @cert_password.setter
  def cert_password(value) -> None: ...

  @property
  def cert_subject() -> str: ...
  @cert_subject.setter
  def cert_subject(value) -> None: ...

# In class WSServer:
@property
def on_ssl_connection_request() -> Callable[[WSServerSSLConnectionRequestEventParams], None]: ...
@on_ssl_connection_request.setter
def on_ssl_connection_request(event_hook: Callable[[WSServerSSLConnectionRequestEventParams], None]) -> None: ...

Remarks

This event fires when an SSL connection is requested and ssl_provider is set to Internal. This event provides an opportunity to select an alternative certificate to the connecting client. This event does not fire when ssl_provider is set to Platform.

This event allows the class to be configured to use both RSA and ECDSA certificates depending on the connecting client's capabilities.

ConnectionId is the connection Id of the client requesting the connection.

SupportedCipherSuites is a comma-separated list of cipher suites that the client supports.

SupportedSignatureAlgs is a comma-separated list of certificate signature algorithms that the client supports.

CertStoreType is the store type of the alternate certificate to use for this connection. The class supports both public and private keys in a variety of formats. When the cstAuto value is used, the class will automatically determine the type. This property can take one of the following values:

CertStore is the store name or location of the alternate certificate to use for this connection.

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).

CertPassword is the password of the certificate store containing the alternate certificate to use for this connection.

CertSubject is the subject of the alternate certificate to use for this connection.

The special value * matches any subject and will select the first certificate in the 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.

on_ssl_status Event

This event is fired to show the progress of the secure connection.

Syntax

class WSServerSSLStatusEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def message() -> str: ...

# In class WSServer:
@property
def on_ssl_status() -> Callable[[WSServerSSLStatusEventParams], None]: ...
@on_ssl_status.setter
def on_ssl_status(event_hook: Callable[[WSServerSSLStatusEventParams], None]) -> None: ...

Remarks

The event is fired for informational and logging purposes only. It is used to track the progress of the connection.

on_web_socket_open_request Event

Fired when a client attempts to open a WebSocket.

Syntax

class WSServerWebSocketOpenRequestEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def request_uri() -> str: ...

  @property
  def host_header() -> str: ...

  @property
  def origin_header() -> str: ...

  @property
  def sub_protocols() -> str: ...
  @sub_protocols.setter
  def sub_protocols(value) -> None: ...

  @property
  def extensions() -> str: ...

  @property
  def request_headers() -> str: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

  @property
  def response_headers() -> str: ...
  @response_headers.setter
  def response_headers(value) -> None: ...

# In class WSServer:
@property
def on_web_socket_open_request() -> Callable[[WSServerWebSocketOpenRequestEventParams], None]: ...
@on_web_socket_open_request.setter
def on_web_socket_open_request(event_hook: Callable[[WSServerWebSocketOpenRequestEventParams], None]) -> None: ...

Remarks

This event fires when a client connects. It provides an opportunity to inspect the WebSocket request and either accept or reject the connection attempt.

By default, the class will accept the connection. You do not need to set anything to accept the connection. The class will return a StatusCode of 101 to the connecting client and the request will proceed as normal. To reject a connection, set StatusCode to an HTTP error code, such as 401.

ConnectionId identifies the connecting client.

RequestURI provides the URI requested by the connecting client. This may be used to implement logic to select appropriate SubProtocols or determine if the connection should be accepted based on access restrictions to the URI.

HostHeader holds the value of the Host header sent by the client.

OriginHeader holds the value of the Origin header sent by the client.

SubProtocols holds a comma separated list of subprotocols sent by the client (if any). Set SubProtocols to the selected value from the list sent by the client. The class will return this value to the client as the subprotocol the server has selected.

Extensions provides a list of extensions supported by the client.

RequestHeaders contains the HTTP headers sent in the request by the connecting client.

StatusCode determines success or failure. The value 101 (default) indicates success. This may be set to any HTTP status code. For instance a value of 401 indicates an authorization failure.

ResponseHeaders may be set to include additional headers in the response. This is typically used when rejecting a request. For instance when StatusCode is set to 401 you might set ResponseHeaders to "WWW-Authenticate: Basic realm="Secure Realm"" to request authorization from the connecting client.

WSServer Config Settings

WebSocketServer Config Settings

TCPServer 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-----

Base Config Settings

WSServer Errors

WSServer Errors

TCPServer Errors

SSL Errors

TCP/IP Errors