How to Subscribe to Salesforce Platform Events with Mule 4

In this article, please follow an example in Trailhead Define and Publish Platform Events.

1. Login to Salesforce and create a Salesforce Platform Events. Please follow the example in the Trailhead to create a Platform Events “Cloud_News__e”.
2. Create a Mule application
2-1. Create a component Subscribe Channel, then specify “/event/Cloud_News__e” as Streaming channel.
2-2. Create a logger component to show payload, so that we will see the received message on Console.
Example)

<flow name="SampleFlow" doc:id="d25ff96a-aec9-45ee-89f2-74080fb83b45" >
  <salesforce:subscribe-channel doc:name="Subscribe channel" doc:id="cb21f452-9280-41f8-ba52-93c49a03ea38" config-ref="Salesforce_Config" 
   streamingChannel="/event/Cloud_News__e"/>
  <logger level="INFO" doc:name="Logger" doc:id="5ebd77bf-87de-4f55-ab81-2af3abbe2bee" message="#[payload]"/>
</flow>

3. As written in the above Trailhead content, Publish a Platform Event Message to “Cloud_News__e“. You can use Apex code, Process, Flow, or Salesforce APIs. For example, you can request POST with the below body.

{
   "Location__c" : "Mountain City",
   "Urgent__c" : true,
   "News_Content__c" : "Lake Road is closed due to mudslides."
}

4. You will see something like below in the Console log, which is equivalent to the above POST body.

INFO  2019-10-26 16:11:50,483 [[MuleRuntime].cpuLight.05: [test].SampleFlow.CPU_LITE @2b42bef0] 
[event: e00096e0-f7bf-11e9-b534-8c85907d741e] org.mule.runtime.core.internal.processor.LoggerMessageProcessor: 
{data={schema=eGRz2Sfoy-YO9mVvH8J4fg, 
payload=
{News_Content__c=Lake Road is closed due to mudslides.,
 CreatedById=0050o00000U3Q8vAAF,
 CreatedDate=2019-10-26T07:12:01.026Z,
 Location__c=Mountain City, Urgent__c=true},
 event={replayId=49544589}},
 channel=/event/Cloud_News__e}