How to keep node_modules in sync with package.json
Today we will be focusing on how to keep our local node_modules up to date whenever the package.json is modified when we pull from remote or switch between branches.
As JS developer, when we work on projects we frequently need to run
npm install command whenever we pull or checkout to a different git branch where package.json is modified.
In majority of the cases, the dependencies won’t cause any issues, but if there any breaking change introduced by the dependency package then we need to reinstall. We somehow forget to run the command (I mostly forget it at least 😛).
How do we automate this?
Well, it quite simple. Hooks!!!
Yes. Git hooks.
We can make use git hooks to trigger
npm install command if a package.json file has been updated.
Script to run inside git hooks.
changed_files="$(git diff-tree -r --name-only --no-commit-id ORIG_HEAD HEAD)"
echo "$changed_files" | grep --quiet "$1" && eval "$2"
check_run package.json "npm install"
Here we check whether package.json file is present in the diff between current HEAD and original HEAD. To learn more about refer to this Q&A
To run the above script on
- git pull — Run
chmod +x post-mergeto make it executable then
mv post-merge .git/hooks/put it into git hooks.
- git checkout — Run
chmod +x post-checkoutto make it executable then
mv post-checkout .git/hooks/
This article was originally published at bharathvaj.me