Publishing Events

Once data is analyzed by WSO2 SP, the resulting data is output via a selected transport to the required interface in the required data format. In order to output results, a Siddhi application that processes events must have one or more sinks configured in it.

A sink configuration specifies the following:

Source types

Each sink configuration must specify the transport type via which the events to be published by the Siddhi appliction should be published. The parameters to be configured for the transport differs based on the transport types. The following is the list of transport types supported by WSO2 SP. For detailed instructions to configure a sink of a specific transport type, click on the relevant link.

A sink could also be defined externally, and referred to from several siddhi applications as described below. A <PROFILE> could refer to dashboard, editor, manager or worker.

Multiple sinks can be defined in the <SP HOME>/conf/<PROFILE>/deployment.yaml file. The following is a sample configuration of a sink.

siddhi:
  refs:
    -
      ref:
        name: 'sink1'
        type: '<sink.type>'
        properties:
          <property1>: <value1>
          <property2>: <value2>

You can refer to a source configured in the  <SP HOME>/conf/<PROFILE>/deployment.yaml file from a Siddhi application as shown in the example below.

@Sink(ref='sink1', @map(type='json', @attributes( name='$.name', amount='$.quantity')))
define stream SweetProductionStream (name string, amount double);

Event format

The format in which the output events need to be published is specified as the mapping type in the sink configuration. The parameters related to mapping that need to be configured differ based on the mapping type. The following is a list of supported mapping types. For detailed instructions to configure each type, click on the relevant link.