Question

I use git as my version control system and have set up a Gerrit site to do the code review. I would like to create a hook to do the following:

• When the admin clicks the Submit button, a file (called version.txt)
  should be modified.
• Script should open the file.

• Find the following text (where the ID may change)

  #version Change-Id: Ie1411d50f6beb885bc3d3b7d8c587635e1446c18

• Replace the Change-Id with the Change-Id of the new patch.

• So, if the patch being merged has the Change-Id: I1c25f7b967084008b69a6a8aefa6e3bb32967b82 then the version.txt file
  should contain the following string after the script is run:

  #version Change-Id: I1c25f7b967084008b69a6a8aefa6e3bb32967b82

• Then the hook should create a new commit (since now there has been a change in one of the files) and push this last commit to master.

I feel this would be possible using a change-merged hook. Am I right?

Thanks in advance.

Answer 1

Something like this:

#!/bin/sh

# See link below for actual command line format
# you may need to make the argument parsing more robust
CHANGE_ID=$2

git clone ${GIT_DIR} /tmp/repo-${CHANGE_ID}
echo "#version Change-Id: ${CHANGE_ID}" > /tmp/repo-${CHANGE_ID}/version.txt
GIT_DIR=/tmp/repo-${CHANGE_ID}/
cd /tmp/repo-${CHANGE_ID}/
git add /tmp/repo-${CHANGE_ID}/version.txt
git commit -m'Auto-updated version'
git push origin master
rm -rf /tmp/repo-${CHANGE_ID}/

http://gerrit-documentation.googlecode.com/svn/Documentation/2.2.2/config-hooks.html#_change_merged

On principle, I’m not a fan of this approach, and I think it should be better done on the way out (e.g., a “install.sh” script, which can use git commands to extract the revision hash, and generate a version.txt file from there). But something like this should put you in the right direction. This is untested, but it should work.