title: How to find which activity called another activity in my ADF Pipeline
body: <p>I have created a pipeline (LogPipeline) that logs other pipelines' status to a database. The idea is that every pipeline will call the LogPipeline at the start and at the end by passing pipeline name and pipeline ID along with other parameters like started/ended/failed. </p>
  
  <p>The last parameter is "Reason" where I want to capture the error message of why a pipeline may have failed.</p>
  
  <p>However, in a given pipeline there are multiple activities that could fail. So I want to direct any and all failed activities to my Execute Pipeline activity and pass the error message. </p>
  
  <p>But on the Execute Pipeline when filling out the parameters, I can only reference an activity by its name, e.g. <code>Reason = @activity['Caller Activity'].Error.Message.</code><br>
  However, since multiple activities are calling this Execute Pipeline, is there a way to say 
  <code>Reason = @activity[activityThatCalledExecutePipeline].Error.Message?</code></p>