Solace producer flow-node

5 minute read

Overview

The Solace Producer flow-node writes messages to Solace topics. Using Solace is useful when implementing an event-driven microservice architecture.

It is part of the Solace plugin, @axway/api-builder-plugin-ft-solace. The plugin also contains a Solace Consumer flow-trigger and the Solace Acknowledge flow-node. They can be used independently in that your application may only just publish messages to Solace, it does not necessarily have to consume them.

You can install the Solace plugin from the Plugins page, or execute the following command:

npm install @axway/api-builder-plugin-ft-solace

For additional getting started information, refer to the Getting Started With API Builder.

Methods

The following sections provide details of the available Solace Producer flow-node methods.

Publish String

Publish text message as String to Solace topic.

Parameters

Outputs

Publish JSON

JSON encodes and publishes a message to a Solace topic.

Parameters

Outputs

Publish Binary

Publish message with attached binary to Solace topic.

Parameters

Outputs

How to use the Solace Producer

After the installation of the Solace plugin, you will find the Solace Producer flow-node in the list of available Flow-Nodes > Core in the left-hand panel of the flow editor:

Prerequisites

This example requires the example from the Solace Consumer flow-trigger. The Solace Consumer is required to be created before this example so that it creates a valid Connection ID that will be used in this example.

Example - Publish JSON to Solace

First create a new flow following the instructions on Create a new Flow page.

Once you have created a new blank flow, you will want to drag and drop the Solace Producer from the Flow-Nodes > Core panel on the left, into the flow graph on the right.

In this example, we will encode an Object as JSON and publish it to a Solace topic, “messages”. Configure the flow-node to have the properties as shown below. The Connection ID that is used here is a string identifier and can be found on the flow that contains the Solace Consumer configuration panel (e.g. “Consumer Flow”). Unless you have more than one, it is typically just, “solace”.

Click on the debugger icon in the upper-right of the graph, do not change any values, and click Execute Flow, and check your console debug log, you should see:

# Solace Producer debug output
1618853664944 DEBUG [request-id: a4d271b4-fbd8-4bcb-8a6e-d5f86fae7242] Flow invoked by debugger: Solace Producer
1618853664944 DEBUG [request-id: a4d271b4-fbd8-4bcb-8a6e-d5f86fae7242] Waiting: Publish JSON (solace.1)
1618853664944 DEBUG [request-id: a4d271b4-fbd8-4bcb-8a6e-d5f86fae7242] Invoking: Publish JSON (solace.1)
1618853664959 DEBUG [request-id: a4d271b4-fbd8-4bcb-8a6e-d5f86fae7242] Publish JSON (solace.1) route: []
1618853664959 DEBUG [request-id: a4d271b4-fbd8-4bcb-8a6e-d5f86fae7242] Flow debugging completed: Solace Producer

The flow-node successfully published JSON to Solace.

Example - Behave only as a Solace Producer

It is not possible for your application to behave only as a Solace producer. This is because the Solace server configuration settings on the Solace Consumer flow-trigger configuration panel, and it is a limitation with the product that flow-trigger connections cannot be managed independently. It is possible for your application to behave as a Solace Producer, but it is necessary to create a Solace Consumer, and then manually disable it. Follow the instructions to create a Solace Consumer, and then in a text editor, edit your triggers/solace.yaml file, and manually disable the flow-trigger by setting the “solace-1” flow-trigger property “enabled” to false (line 15):

# solace.yaml
channels:
  solace:
    name: Solace
    enabled: true
    parameters:
      url: 'tcp://localhost:55555'
      vpnName: default
      userName: admin
      password: admin
triggers:
  solace-1:
    name: Solace Consumer
    parameters:
      topicName: messages
    enabled: false
    invoke:
      flow: SolaceConsumer
      parameters:
        request: $.request.message
    channel: solace