Sends WebSocket messages to the specified WebSocket server. The first input feature will cause the WebSocketSender to initialize a connection with the specified WebSocket server. The specified Data to Transmit will be sent to the WebSocket server for each input feature of the WebSocketServer, including the first feature that initiated the connection.
Usage Notes
The performance of this transformer is dependent on the amount of memory allocated to the Java Virtual Machine (JVM). The following environment variables allow you to specify memory available to Java Plugins:
- FME_JVM_MIN_HEAP_SIZE: Initial heap size for initializing the JVM. Default value is 1024K.
- FME_JVM_MAX_HEAP_SIZE: Maximum heap size for initializing JVM. Default value is 16384K.
If unset, the JVM applies the default values. If set, the values must be multiples of 1024K (for example, 4M and 64M, or 4096K and 32768K).
Note: To pass additional parameters used by FME to the Java Virtual Machine, use the JAVA_TOOL_OPTIONS environment variable.
Input Ports
Input
This transformer accepts any feature.
Output Ports
Output
All input features are directly output through this port after the specified data has been transmitted.
Parameters
WebSocket Server URL
The URL of the remote WebSocket server that the WebSocketSender will connect to and transmit WebSocket messages. The default value is ws://localhost:7078. To initiate a secure connection to a WebSocket server using TLS, specify wss://<hostname>:<port>.
Verify SSL Certificates
If Yes is specified, either explicitly or through a parameter, the WebSocketSender verifies the certificate (or chain of certificates) of the WebSocket server before establishing a connection.
Connection Preamble
If this optional parameter has a value, then the WebSocketSender will transmit the contents of this parameter to the remote WebSocket server before transmitting the specified data.
To connect to the FME Server WebSocket server, use the following preamble:
{
"ws_op" : "open",
"ws_stream_ids" : ["<STREAMID>", "<STREAMID>", "<STREAMID>", ...]
}
To specify this preamble, click the ellipsis (...) to open the Connection Preamble dialog. Under FME Server WebSocket Preambles, select the Open Public Stream template. Then, specify a ws_stream_ids value.
ws_stream_ids identifies one or more message streams in order for the WebSocket server to associate them with the correct requesting application.
Data to Transmit
This parameter specifies the data to transmit to the specified WebSocket server. This may be a text value, an attribute value, or the result of an expression.
To send a message to the FME Server WebSocket server, use the following template:
{
"ws_op" : "send",
"ws_msg" : "<MESSAGE>"
}
To specify this template, click the ellipsis (...) to open the Data to Transmit dialog. Under FME Server WebSocket Messages, select the Send Message template. Then, specify a ws_msg value.
Editing Transformer Parameters
Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click 
beside the applicable parameter. For more information, see Transformer Parameter Menu Options.
Transformer Categories
FME Licensing Level
FME Professional edition and above
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