title: Jenkins and Git - how to grab a committer's name?
body: <p>I am trying to get more GIT commit information into a HipChat room. </p>
  
  <p>I see there are a number of GIT variables that can be used in jenkins.  I am working in the Execute Shell step of a job.</p>
  
  <p>These work:</p>
  
  <pre><code>echo "${GIT_BRANCH}"
  
  echo "${GIT_URL}"
  
  echo "${GIT_COMMIT}"
  </code></pre>
  
  <p>These do not:</p>
  
  <pre><code>echo "${GIT_COMMITTER_EMAIL}"
  
  echo "${GIT_COMMITTER_NAME}"
  
  echo "${GIT_AUTHOR_EMAIL}"
  
  echo "${GIT_AUTHOR_NAME}"   
  
  echo "${GIT_USER}"
  </code></pre>
  
  <p>Question 1: how come the vars above don't work?</p>
  
  <p>This works:</p>
  
  <pre><code>git show --name-only
  </code></pre>
  
  <p>Question 2: How come I cant do 
      Foo = "git show --name-only"
  And use Foo else where in the job, ie- send to HipChat?</p>
  
  <p>I see there is a plugin envInject.  But this is to write to a file in the workspace doing the execute shell step, then read from that file.  This seems to be a bit overkill for what I am trying to do.  </p>
  
  <p>Question 3: is the envInject my only option?</p>