Need mechanism to update JIRA Resolution field during a transition without user interaction

[John O_Leary]

During a workflow transition need a Post function that scans the Bitbucket commit string for something like
"# fix LMSTAX-1234" ? 
"# reject LMSTAX-1234" ?
"# invalid LMSTAX-1234" ?

Based on the keywords "fix or invalid" it automatically transitions and then changes the resolution field of issue LMSTAX-1234 to the value in the commit message that precedes the issue ID.