Starting a process instance using REST call

[bsong]

I am trying to start a process instance using REST API. 

It can start the process and pass the variable but I also want to retrieve the data from the database. 

According to the variable I pass into the body. 

(POST) http://localhost:8080/activiti-app/api/runtime/process-instances?tenantId=tenant_1

{
"processDefinitionId":"vacationRequest",
"businessKey":"vacationRequest",
"variables": [
{
"name":"userId",
"value":"user123"
}
]
}

When I open the activiti app Task I can see the process is running and the userId is passed in, but I cannot get the userdata from Mysql database.  

If I start the process in the Task App it will work, but not uring REST call. 

Thanks, 

Brian 

[darkwind]

I'm not sure if you want to get the user involved by this process. if you want to get this ,you can call 

```

/runtime/process-instances/{processInstanceId}/identitylinks

```