title: Jenkins pipeline conditional branch builds
body: <p>Using a multibranch pipeline I'd like trigger a slightly different build and deploy procedure depending on which git branch has triggered the build.</p>
  
  <p>The two approaches I can think of are :
  1) Use a different jenkins file in each branch
  2) Use a series of when {branch 'X'} blocks in the jenkins file</p>
  
  <p>The first approach mean I'll need to be careful when merging branches which I know I'll forget to be at some point.</p>
  
  <p>The second approach is pretty messy but does mean I can use just one Jenkins file.</p>
  
  <p>I can't believe there isn't a better way than these two approaches.</p>