Rails and Git hooks

Automate your repeated task like bundle install and rake db:migrate on every pull.


  • Enter into hooks directory in your projects.
cd myawesomeproject/.git/hooks
  • Create a post-merge file in hooks directory.
touch post-merge
  • Open the post-merge file.
vim post-merge
  • Add the following script to your file:
#/usr/bin/env bash
changed_files="$(git diff-tree -r --name-only --no-commit-id ORIG_HEAD HEAD)"

echo $changed_files

check_and_run_bundle() {
  echo "$changed_files" | grep -E --quiet "$1" && eval "$2"

check_and_run_bundle Gemfile "bundle install"

  git diff --name-only HEAD@{1} HEAD | grep -E "db/migrate" && eval "rake db:migrate"

  • Save and exit.
  • File is a shell script so we need to make it executable.
chmod +x post-merge
  • From now on everypull script will check if any new dependency(Gem) or new migration it will be resolved automatically.

Happy Coding :)

Written on April 17, 2015

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