When using the task query REST API from within an ADF application to show list task, access to the initiator of the workflow is required. The API response has a field called 'processInstanceStartUserId' but it is always set to null. Note that the same field does actually hold the initiator ID in other REST responses such as when getting a task.
Steps to reproduce
1. Install vanilla OOTB APS v220.127.116.11.
3. App Designer > Apps > Import App 'test.zip' and publish it > Create 3/4 tasks.
4. Get taskId from:
http://localhost:8080/activiti-admin/#/login > Login in as admin (username and password) > Tasks > Use any ID/
5. Invoke http://localhost:8080/activiti-app/api-explorer.html#!/tasks/getTaskUsingGET > Response >
processInstanceStartUserId = 1
Response is: processInstanceStartUserId = null
[ Note ] : activiti-admin > Apps > App ID can be obtained from here.
processInstanceStartUserId should be set with the correct value.
processInstanceStartUserId field value is null.