typicode/husky : Git hooks made easy 🐶 woof!

Hooks

git hooks
Run a program before certain points in gits execution.
pre-commit and pre-push hooks are probably the most interesting.

They are defined in .git/hooks. You can find some example files in that directory. Remove their .sample suffix to test them out.

The githooks are saved locally and not pushed to the remote. This is obviously a problem when working in a team but the .git/hooks folder can be changed globally or for the current repository with the core.hooksPath setting.

This is obviously never going to happen but you could skip githooks with:

git commit --no-verify
git push --no-verify

# Or if you want to really quickly skip it ;)
git commit -n

Husky

Or, use Husky to easily make the git hooks part of the repository itself and share it with the entire team.

npm install husky --save-dev
npx husky init

This will add a prepare npm script in your package.json. The prepare script runs after an npm install to ensure things are setup for everyone.

"scripts": {
  "prepare": "husky"
},

And it creates a .husky/pre-commit which you can try out by doing a git commit!
Avoid having to git reset HEAD~ all the time by ending your script with exit 1 while testing/setting it up.

Finally it sets the core.hooksPath to .husky/_. Husky creates files in that directory to link all githooks with the h shell script which will execute a .husky/SOME_GITHOOK if it exists.
Husky also adds a gitignore to the _ folder to keep the generated files out of your git repository.

git config core.hooksPath
# --> .husky/_

Script h

In this order:

• If HUSKY=2 it executes set -x to print commands with arguments
• If the .husky/XXX file does not exist (with XXX for example pre-commit), the script exits
• If ~/.config/husky/init.sh (or $XDG_CONFIG_HOME/husky/init.sh) exists, it executes it
  • This is the place to setup PATH, or set an environment variable like NVM_DIR
• If HUSKY=0 the script exits
• It adds node_modules/.bin to the PATH
• It executes .husky/XXX (stops on first error)

CI/CD

You may not be installing the devDependencies during a production build. To avoid the prepare npm script from failing:

"scripts": {
  "prepare": "husky || true"
},

Project Not in Git Root Directory

Prepush script that works around the frontend project package.json not being in the root of the git repository.

Set the package.json script manually and then do an npm install.

"scripts": {
  "prepare": "cd .. && husky frontend/.husky"
},

The script with some path juggling:

#!/bin/sh

# Path Juggling
originalPath=`pwd`
if [ "`git rev-parse --show-cdup`" != "" ]; then cd `git rev-parse --show-cdup`; fi
cd ./frontend-project-folder/

# Linting
npm run lint
if [ $? -ne 0 ]; then
    cd $originalPath
    exit -1
fi

# Testing
npm test
if [ $? -ne 0 ]; then
  cd $originalPath
  exit -1
fi

# Build
npm run build
hasBuildErrors=$?

cd $originalPath
exit $hasBuildErrors

Alternatives

toplenboren/simple-git-hooks : A simple git hooks manager for small projects

evilmartians/lefthook : Fast and powerful Git hooks manager for any type of projects

pre-commit/pre-commit : A framework for managing and maintaining multi-language pre-commit hooks