git pre-commit hook preventing large files

_Instructions.md

Usage

You can use in two ways.

1. Directly as the pre-commit hook in your .git/hooks folder.

2. With Husky by updating your package.json with:

"husky": {
    "hooks": {
      "pre-commit": "sh ./some-path/pre-commit-prevent-large-files.sh"
    }
}

Installation

@guysmoilov wrote an awesome installer script over here that means this hook will be added to all future repos you clone; how cool!

Credits

Based on @kiwidamien's original gist here

Alternatives

pre-commit is "a framework for managing and maintaining multi-language pre-commit hooks" and has a hook you can plug-in called: check-added-large-files. pre-commit is built with Python though, so you'll need Python installed.

Use a GitHub Aaction (see .yml file)

pre-commit-prevent-large-files.sh

#!/bin/bash

# This is a pre-commit hook that ensures attempts to commit files that are
# larger than $limit to your _local_ repo fail, with a helpful error message.

# Maximum file size limit in bytes
limit=$(( 5 * 2**20 )) # 5MB
limitInMB=$(( $limit / 2**20 ))

# Move to the repo root so git files paths make sense
repo_root=$( git rev-parse --show-toplevel )
cd $repo_root

empty_tree=$( git hash-object -t tree /dev/null )

if git rev-parse --verify HEAD > /dev/null 2>&1
then
	against=HEAD
else
	against="$empty_tree"
fi

# Set split so that for loop below can handle spaces in file names by splitting on line breaks
IFS='
'

echo "Checking staged file sizes"
shouldFail=false
# `--diff-filter=d` -> skip deletions
for file in $( git diff-index --cached --diff-filter=d --name-only "$against" ); do
	# Skip for directories (git submodules)
	if [[ -f "$file" ]]; then
		file_size=$( ls -lan $file | awk '{ print $5 }' )
		if [ "$file_size" -gt  "$limit" ]; then
	    	echo File $file is $(( $file_size / 2**20 )) MB, which is larger than our configured limit of $limitInMB MB
        	shouldFail=true
		fi
	fi
done

if $shouldFail
then
    echo If you really need to commit this file, you can push with the --no-verify switch, but the file should definitely, definitely be under $limitInMB MB!!!
	  echo Commit aborted
    exit 1;
fi

z-lfs-warning.yml

# This workflow will check for large files being added in PRs
# and label the PR if one is found that exceeds the configured limit.
#
# For more information, see: https://github.com/marketplace/actions/lfs-warning

name: Large file size warning

on: 
  pull_request:
    # Ignore some files to avoid consuming Actions minutes unnecessarily 
    # for file types we're fairly confident we'll never need to worry about
    paths-ignore: 
      - '**.config'
      - '**.cs'
      - '**.cshtml'
      - '**.cs'
      - '**.csproj'
      - '**.cmd'
      - '**.dockerignore'
      - '**.gitignore'
      - '**.graphql'
      - '**.jsx?'
      - '**.md'
      - '**.props'
      - '**.ps1'
      - '**.scss'
      - '**.sh'
      - '**.sln'
      - '**.tsx?'
      - '**.yml'
      - '**/appsettings.*.json'
      - '**/Dockerfile'
      
jobs:
  run-check:
    runs-on: ubuntu-latest
    steps:
    - uses: actionsdesk/lfs-warning@v2.0
      with:
        #token: ${{ secrets.GITHUB_TOKEN }} # Optional
        filesizelimit: '5242880' # 5MB

Thanks @Cyberbeni, updated

I put a GitHub action in place instead

@benmccallum is that available at all? :D

Hey @george-angel , just added a yml file that details how we still do it in a GH Action.