Using SapServer with SAP NetWeaver

This is a short primer that explains how to use the SapServer class with a SAP NetWeaver 7 install, with SAPGUI. It is meant only as a guide, and is not designed to be all-encompassing.

The code below installs the function "Z_HELLO" and begins accepting and listening for connections from the SAP system.

SapServer1.AcceptConnections("Hello.App", "localhost", "sapgw00");
SapServer1.InstallFunction("Z_HELLO", "Simple greeting app.");
SapServer1.Listening = true;

Note that if the UseClientConnection config is set to true, or if the SapConnectionType property is set to ctNetWeaver (default), you must also set the appropriate properties. So the code would look like this instead:

SapClient1.Config("UseClientConnection=true");
SapClient1.SapConnectionConnectionType = ctNetWeaver
SapClient1.SapConnectionClient = "000"
SapClient1.SapConnectionDestination = ""
SapClient1.SapConnectionHost = "localhost"
SapClient1.SapConnectionUser = "BCUSER"
SapClient1.SapConnectionPassword = "minisap"
SapClient1.SapConnectionSystemNumber = 0
SapClient1.AcceptConnections("Hello.App", "localhost", "sapgw00")
SapServer1.InstallFunction("Z_HELLO", "Simple greeting app.")
SapClient1.Listening = true

Note that the credentials above are for connecting to a trial NetWeaver installation. You will need to provide your own credentials when connecting to your own SAP installation. Also, please ensure that all dependencies in the Dependencies section below are fulfilled.

Once you've called AcceptConnections , installed your functions, and set Listening to true as shown above, you may use the SAP NetWeaver system to execute your functions. To access this functionality from within NetWeaver, the first thing you need to do is Register an RFC Destination. Then you need to create a new function which is remote enabled. Finally, you need to execute that function on the RFC destination you created. The instructions below outline how to do this on the NetWeaver 7 platform with SAPGUI.

Creating an RFC Destination

First run transaction SM59, which manages RFC Connection configuration. Open the "TCP/IP connections" branch and then click the "Create" button. Under "RFC Destination" put in a name that will identify this destination. For this example, we're using "TESTDEST". Click the "Technical Settings" tab, and under "Activation Type" slick the "Registered Server Program" radio button. Below that, set the "Program ID" field to the same ProgramId you passed into the AcceptConnections method ("Hello.App" in this case).

You can now click the "Connection Test" button, and NetWeaver will attempt to connect to and ping your server application. You will not see this in the FunctionCall event, as the class will automatically respond to a ping. You may override this functionality by installing "RFC_PING" with InstallFunction.

Creating a new function

To create a new function you must first define a new function group, and then add a function module to that group. To do this, open the Object Navigator, or execute transaction SE80. On the left menu screen, click the "Repository Browser" bar. In the selection box displayed below, choose "Function Group". Under that, type a name for your new function group and press enter. This function group must start with "Z_" (capital Z, underscore), otherwise you will be asked for an access key. For this example, we will use "Z_TEST_GROUP". If the function group does not exist, you will be asked if you want to create the object. Select Yes, fill in the short text field, (just a simple description) and click Save. On the next screen, leave the "Package" field empty and click "Local Object" to save the function group.

You should now have your new function group listed in the left hand frame. Right click on your function group and select Create->Function Module. Put in a new name for your function module. This must match the name of the function you install with the SapServer class's InstallFunction method. Like the function group, it should also start with "Z_". For this example, we'll use "Z_HELLO". This will be the name of the function you'll implement on your server, and is the same name you'll register with the InstallFunction method.

The new function will now be displayed in the right frame. Click the "Attributes" tab, and under Processing Type select the "Remote-Enabled Module" radio button. The "Import" tab allows you to specify import parameters. These correspond to the ReceiveParams in the SapServer component. For this example, we'll add two parameters, "FIRSTNAME" and "LASTNAME". The "Typing" field should be set to "TYPE", and the Associated Type to "CHAR256" for both parameters. Check the "Pass Value" box for both as well.

Next, click the "Export" tab, and create a parameter called "GREETING", with typing "TYPE" and associated type "CHAR512". Pass Value should also be checked here as well. This corresponds to the ReplyParams property in the SapServer class. You may also add tables using the "Table" tab, but that will not be necessary for this example. Under the "Exceptions" tab you may define any exception you like. (There is no master list, you just name them as you see fit). Press ctrl-S to save (Or select "Function Module->Save" from the menu bar).

Running your function

Close all the open windows until you're back at the home screen. Now run transaction SE37. Put the name of the function you wish to call in the "Function Module" field (in this case "Z_HELLO") and click the "Display" button. Press F8 to test the function module. On this screen fill in the "RFC Target sys" field with the RFC destination you created above ("TESTDEST"). Fill the import parameters with the data you wish to send to the server. Check the "Uppercase/Lowercase" checkbox if you don't want NetWeaver to send uppercase parameter values. Now press either the Activate or Debugging button to execute the function.

If everything is set up correctly, the FunctionCall event will now fire with the FunctionName parameter "Z_HELLO". Add the FIRSTNAME and LASTNAME ReceiveParams and call UpdateReceiveParams(). Add the greeting you wish to send to the ReplyParams property, and then call SendReply(). For instance:

void SapServer1_OnFunctionCall(object sender, SapserverFuncionCallEventArgs e) {
  if (e.FunctionName.Equals("Z_HELLO")) {
    SapServer1.ReceiveParams.Add(new nsoftware.InERP.SapParam("FIRSTNAME", "",ptCharacters));
    SapServer1.ReceiveParams.Add(new nsoftware.InERP.SapParam("LASTNAME", "", ptCharacters));
    SapServer1.UpdateReceiveParams();
         
    String greeting = "Hello " + SapServer1.ReceiveParams.ElementAt(0).Value + " " +
                      SapServer1.ReceiveParams.ElementAt(1).Value + ", I hope that you are well.";
    SapServer1.ReplyParams.Add(new nsoftware.InERP.SapParam("GREETING", greeting, ptCharacters));
    SapServer1.SendReply();
  }
}

The result of calling this function from NetWeaver with FIRSTNAME "John" and LASTNAME "Smith" is: "Hello John Smith, I hope that you are well.", and is contained in the "GREETING" export parameter.

For more detailed information creating function modules, including the use of tables, please see: http://help.sap.com/saphelp_nw04/helpdata/en/26/64f61dfa8911d386e70000e82011b8/frameset.htm

Creating New tables

Transaction Code SE11 allows you to display existing tables or create new ones. Run SE11 and select the "Database table" radio button. Enter a name for your table, making sure it begins with a capital 'Z' character, (in this example, we'll use "ZMYTAB"). Then click the "Create" button. Fill in the short description field first. Then under "Delivery and Maintenance" set the "Delivery Class" to "A". Next click the "Fields" tab and add your fields. The very first field you add should be the key for this table. (This key is necessary and is used by the SAP system). Note that the "KEY" name is reserved, the first field in any table must be a key, and the maximum length for a key is 120 characters. (The maximum length for all other fields is 255 characters).

When adding fields, you may use predefined types or use existing data elements. For this example we will manually create each fields. To begin doing this, press the "Predefined Fields" button. Then, on each line enter the name of your field, the Data Type, Length, and Short Description. We'll add two fields this way. The first is named "MYKEY", has the "Key" checkbox marked, data type is CHAR, and length is 120. The next data element is named "DATA", data type CHAR, and length 255 (the maximum length for a field). You may also create other types of fields, but note that for some Data Types (INT1, INT2, etc) the SAP system will automatically select the correct field length.

After adding all of your data fields, you're not quite done yet. Click the "Extras" menu and then "Enhancement Category". Click the checkbox on the error message that pops up, and then on the "Maintain Enhancement Category" window select the "Cannot Be Enhanced" radio button, then press the "Copy" button.

Press CTRL-S (or Table->Save) to save the table. On the "Create Object Directory Entry" window that pops up, click the "Local Object" button. Ignore the warning message that the application table should be client-specific. We're almost done now. Click the "Technical Settings" button near the top of the current window. Set the "Data Class" field to "USER" and the "Size category" to 0. CTRL-S to save, and then the Back button (or press F3) to exit out. Now select the "Table" menu one last time, and click "Activate." (or press CTRL-F3). Your table is now activated and may be used by the functions you create.

To add a table, find a function you've already created (using the steps above) with Transaction Code SE37. Click the "Change" button, then click the "Tables" tab. Under "Parameter Name", make up a name for your table (eg, "GREETING"). In the "Typing" column put the word "LIKE", and in the "Associated Type" column, the name of the table you created (eg, "ZMYTAB"). Ctrl-S to save and Ctrl-F3 will activate the function. If you press F8 now you will see an entry under "Tables" called "GREETING". You can edit this table to send table data when calling the remote function, and when you add or edit RowData in the FunctionCall event it will show up in a result table of the same name.

Note that you can also use the Column* properties to modify the table. These properties will be populated when RowIndex is set, which will be set back to 0 whenever TableIndex is set.

SapServer Dependencies

In addition to the requirements detailed in Setting Up a Connection with a SAP System, the following services must be added to %WINDIR%\system32\drivers\etc\services, or /etc/services if your system is running Linux or Mac OS X. If SAP NetWeaver is already installed on the machine,then no further action is required.