Git config with directory scope, containing multiple repositories

The solution I came up with is inspired from Scott Weldon's answer. Since it was not directly applicable for my case, I adapted the hook's bash script and improved several parts*.

Assume the following directory structure from the home directory:

~
   .gitconfig           // [init] templatedir
   .git-template
      hooks
         post-checkout  // our bash script
   MyDomain
      .gitconfig        // [user] name, email

Initially I let Git know where my template directory is. On Windows, you may need to specify the absolute path instead (C:/Users/MyUser/.git-template).

git config --global init.templatedir '~/.git-template'

In ~/MyDomain/.gitconfig I store the configuration for that directory (domain), which should be applied to all repositories inside it and its subdirectories.

cd ~/MyDomain
git config --file .gitconfig user.name "My Name"
git config --file .gitconfig user.email "[email protected]"

The interesting part is the post-checkout bash script, which defines the post-checkout hook. I used a custom user.inferredConfig flag to execute it only once (on git clone), not repeatedly (on git checkout). It would of course also be possible to create a separate file to represent that state.

#!/bin/bash

# Git post-checkout hook for automated use of directory-local git config
# https://stackoverflow.com/a/40450106

# Check for custom git-config flag, to execute hook only once on clone, not repeatedly on every checkout
if grep -q "inferredConfig" .git/config
then
    exit
fi

# Automatically set Git config values from parent folders.
echo "Infer Git configuration from directory..."

# Go upwards in directory hierarchy, examine all .gitconfig files we find
# Allows to have multiple nested .gitconfig files with different scopes
dir=$(pwd)
configFiles=()
while [ "$dir" != "/" ]
do
    # Skip first directory (the newly created Git repo)
    dir=$(dirname "$dir")
    if [ -f "$dir/.gitconfig" ]
    then
        configFiles+=("$dir/.gitconfig")
    fi
done

# Iterate through configFiles array in reverse order, so that more local configurations override parent ones
for (( index=${#configFiles[@]}-1 ; index>=0 ; index-- )) ; do
    gitconfig="${configFiles[index]}"

    echo "* From $gitconfig:"
    # Iterate over each line in found .gitconfig file
    output=$(git config --file "$gitconfig" --list)
    while IFS= read -r line
    do
        # Split line into two parts, separated by '='
        IFS='=' read key localValue <<< "$line"

        # For values that differ from the parent Git configuration, adjust the local one
        parentValue=$(git config $key)
        if [ "$parentValue" != "$localValue" ]
        then
            echo "  * $key: $localValue"
            git config "$key" "$localValue"
        fi
    done <<< "$output"

    # Set custom flag that we have inferred the configuration, so that future checkouts don't need to do it
    git config user.inferredConfig 1
done

*: The changes from the original code include:

1. Works with spaces in paths (especially interesting on Windows)
2. Parses key-value pairs from .gitconfig correctly (don't read lines with for, iterate with while read instead)
3. Checks .gitconfig files from root to local directory, not vice-versa
4. Invokes hook only at initial clone, not at every checkout
5. Output the config settings that are applied on git clone

As a simple solution, use something like autoenv (sorry for the self-advertising) to set your mail address with environment variables:

echo 'export GIT_AUTHOR_NAME="Your name"' > professional/.env
echo 'export GIT_AUTHOR_EMAIL="[email protected]"' >> professional/.env
cd professional