Start and stop Mule Flow at runtime

  • April 13, 2020

MuleSoft provides options to make a flow stop and start at a designated time, as well as to start and stop a flow dynamically/on request.

  • Start flow only once, on project start up
  • Enable and disable flows on demand or from the configuration file

In these cases, if you follow the standard approach, you’ll need to regenerate and redeploy the JAR file. Functionality-wise, there’s no code change.

This tech article explores the options for these cases without regenerating the JAR file:

  • Using Groovy script within the code
  • Using CURL or Postman
  • Using ARM REST services from Mule Flow

Using Groovy script within the code

  1. Add the scripting module to your project if you haven’t previously added it
  2. Add a scripting component like the following:
    3. Start and Stop Mule Flow at Runtime1

This script can switch the status of the flow identified by flow name — that is, if the flow is stopped, it will start and vice versa.

Using CURL or Postman

MuleSoft Anypoint Runtime Manager publishes an API to manage Anypoint Runtime Manager programmatically. One API can also be used to start and stop the specific flow.

ARM API URL: https://anypoint.mulesoft.com/hybrid/api/v1/applications/{applicationId}/flows/{flowId}

Method Name: PATCH

URI Parameters:

  • applicationId: Application ID of the Mule application in a deployed environment; this isn’t the application name. To get the application ID, perform the GET operation on https://anypoint.mulesoft.com/hybrid/api/v1/applications
  • flowId: Flow ID — that is, the flow name given in Anypoint Studio

Body: example {‘desiredStatus’: ‘STARTED’}

ACCESS_TOKEN: The access token to access the MuleSoft Anypoint Runtime Manager API

To change the flow status, run the following CURL command:

Start and Stop Mule Flow at Runtime2

Or use Postman:

Start and Stop Mule Flow at Runtime3

The output of both commands will look like the following example:

Start and Stop Mule Flow at Runtime4

Using ARM REST services from Mule Flow

MuleSoft asset list contain ARM REST Service (RAML) which can be downloaded from https://anypoint.mulesoft.com/exchange/portals/anypoint-platform/f1e97bc6-315a-4490-82a7-23abe036327a.anypoint-platform/arm-rest-services/

The REST service — https://anypoint.mulesoft.com/hybrid/api/v1/applications/{applicationId}/flows/{flowId} — can be triggered from Mule Flow using the HTTP Request component.

Pros and cons of these approaches

Pros Cons
Less Time Consuming Little bit of planning required which approach suits your use case
No Need to do code change and generate the jar As Status change by the method are not persistent so need to change the status after restart

References:

— By Mohammad Mazhar Ansari