This documentation is for WSO2 API Manager 1.10.0 View documentation for the latest release.
Page Comparison - Adding an API Subscription Workflow (v.3 vs v.4) - API Manager 1.10.0 - WSO2 Documentation

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This section explains how to attach a custom workflow to the API subscription operation in the API Manager. First, see Workflow Extensions for information on different types of workflows executors.

Attaching a custom workflow to API API subscription enables you to add throttling tiers to an API that consumers cannot choose at the time of subscribing. Only admins can set these tiers to APIs. It also allows you to restrict restrict API consumers to only subscribe to sandbox, and then go through an approval process to go to the next level of subscription.


Before you begin, if you have changed the API Manager's default user and role, make sure you do the following changes:

  • Give the correct credentials in the <BPS_HOME>/repository/conf/epr files.
  • Change the credentials of the workflow configurations in the registry resource _system/governance/apimgt/applicationdata/workflow-extensions.xml.
  • Point the database that has the API Manager user permissions to BPS.
  • Share any LDAPs, if exist.
  • Change the user credentials in <APIM_HOME>/repository/conf/api_manager.xml file.
  • Change the .ht file of the relevant human task.
  • Change the allowedRoles parameter in the <APIM_HOME>/repository/deployment/server/jaggeryapps/admin-dashboard/site/conf/site.json file.

Configuring the Business Process Server

  1. Download Download WSO2 Business Process Server.    
  2. Set an offset of 2 to the default BPS port in in <BPS_HOME>/repository/conf/carbon.xml file file. This prevents port conflicts that occur when you start more than one WSO2 product on the same server. Also see see Changing the Default Ports with Offset. 

    Code Block

    Tip: If you change the BPS port offset to a value other than 2 or run the API Manager and BPS on different machines (therefore, want to set the hostname to a different value than localhost), you do the following:

    • Search and replace the value 9765 in all the files (.epr) inside <APIM_HOME>/business-processes folder with the new port (9763 + port offset.)Search and replace port 9445 in <APIM


  3. Open the <BPS_HOME>/repository/

    deployment/server/jaggeryapps/admin-dashboard/site/conf/site.json file with the new port (9443 + port offset.)

    conf/humantask.xml file and <BPS_HOME>/repository/conf/b4p-coordination-config.xml file and set the TaskCoordinationEnabled property to true.

    Code Block
  4. Copy the following from <APIM_HOME>/business-processes/epr to <BPS_HOME>/repository/conf/epr folder. If  If the <BPS_HOME>/repository/conf/epr folder isn't there, please create it.

    • SubscriptionService.epr
    • SubscriptionCallbackService.epr
  5. Start the BPS server and log in to its management console (https://<Server Host>:9443+<port offset>/carbon).  

  6. Select Add under the Processes menu and upload t he the <APIM_HOME>/businessbusiness-processes/subscription-creation/BPEL/ file to BPS. This is the business process archive file.
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  7. Select Add under the Human Tasks menu and upload and upload the <APIM_HOME>/business-processes/subscription-creation/HumanTask/ zip file to BPS. This is the human task archived file.

Configuring the API Manager


Open the <APIM_HOME>/repository/deployment/server/jaggeryapps/admin-dashboard/site/conf/site.json


 file and configure "




 under "workflows"


 to point to BPS server


(e.g. "workFlowServerURL": "https://localhost:9445/services/")

Engaging the WS Workflow Executor in the API Manager

First, enable the API subscription workflow.

  1. Log in to APIM admin console (https://<Server Host>:9443/carbon) and select Browse under Resources.

  2. Go to /_system/governance/apimgt/applicationdata/workflow-extensions.xml resource, disable the Simple Workflow Executor and enable WS Workflow Executor. Also specify the service endpoint where the workflow engine is hosted and the credentials required to access the said service via basic authentication (i.e., username/password based authentication).  

    Code Block
        <SubscriptionCreation executor="org.wso2.carbon.apimgt.impl.workflow.SubscriptionCreationWSWorkflowExecutor">
             <Property name="serviceEndpoint">http://localhost:9765/services/SubscriptionApprovalWorkFlowProcess/</Property>
             <Property name="username">admin</Property>
             <Property name="password">admin</Property>
             <Property name="callbackURL">https://localhost:8243/services/WorkflowCallbackService</Property>

    Note that all workflow process services of the BPS run on port 9765 because you changed its default port (9763) with an offset of 2.

    The application creation WS Workflow Executor is now engaged.

  3. Go to the API Store Web interface and subscribe to an API.
    It invokes the API subscription process and creates a Human Task instance that holds the execution of the BPEL until some action is performed on it.

  4. Note the message that appears if the BPEL is invoked correctly, saying that the request is successfully submitted. 

  5. Log in to the Admin Dashboard Web application (https://<Server Host>:9443/admin-dashboard), list all the tasks for API subscription and approve the task. It resumes the BPEL process and completes the API subscription.

  6. Go Go back to the API Store and see that the user is now subscribed to the API.

    Whenever a user tries to subscribe to an API, a request of the following format is sent to the workflow endpoint:

    Code Block
    <soapenv:Envelope xmlns:soapenv=""xmlns:wor="">

     Elements of the above configuration are described below:

    Name of the API to which subscription is requested.
    Version of the API the user subscribes to.
    Context in which the requested API is to be accessed.
    Provider of the API.
    Name of the user requesting subscription.
    Name of the application through which the user subscribes to the API.
    Throttling tiers specified for the application.
    workflowExternalRefThe unique reference against which a workflow is tracked. This needs to be sent back from the workflow engine to the API Manager at the time of workflow completion.

    The URL to which the Workflow completion request is sent to by the workflow engine, at the time of workflow completion. This property is configured under the callBackURL property in the api-manager.xml file.