Git Submodule Setup

Overview

This script automates the setup of Git submodules in your project based on a configuration file. It reads the configuration, checks access to the specified repositories, adds them as submodules at specified paths, and sets them to specific branches or tags.

Features

• Automated Submodule Setup: Quickly add multiple submodules without manual configuration.
• Customizable Paths and Branches: Specify custom local paths and branches or tags for each submodule.
• Access Verification: Checks if you have access to the submodule repositories before adding them.
• Clean Working Directory: Unstages submodule changes to keep your working directory clean.

Prerequisites

• Git: Ensure Git is installed and accessible in your system's PATH.
• Node.js: This script is written in Node.js and requires Node.js to run.
• npm: Node Package Manager, usually installed with Node.js.

Installation

You can use the script as a local dependency in your project or run it directly using npx.

Option 1: Install as a Local Dependency

1. Navigate to Your Project Directory

   cd /path/to/your/project

2. Install the Package

   npm install git-setup-submodules --save-dev

Option 2: Run Directly with npx

You can run the script without installing it by using npx:

npx git-setup-submodules

Configuration

Create a configuration file named .git-setup-submodules in the root directory of your project. This file lists the submodules to be added along with their configurations.

Configuration File Format

Each line in the configuration file represents a submodule and follows this format:

<remote-path>[:<local-path>][#<branch-or-tag>]

• <remote-path>: Path to the submodule repository relative to your Git remote URL base.
• <local-path> (optional): Custom local directory name for the submodule. Defaults to the module name if omitted.
• <branch-or-tag> (optional): Branch or tag to check out. Defaults to main if omitted.

Examples

• Basic Submodule

  libs/utils

  • Clones utils from libs/utils into libs/utils, checking out the main branch.

• Custom Local Path

  apps/website:site

  • Clones website from apps/website into apps/site, checking out the main branch.

• Specific Branch

  libs/logger#v1.2.3

  • Clones logger from libs/logger into libs/logger, checking out the v1.2.3 branch or tag.

• Custom Path and Branch

  apps/website:site#production

  • Clones website from apps/website into apps/site, checking out the production branch.

Comments and Blank Lines

• Lines starting with # or // are treated as comments.
• Blank lines are ignored.

Sample Configuration File

# Submodules Configuration

# Add the utils library
libs/utils

# Add the website app to 'site' directory on 'production' branch
apps/website:site#production

# Add the logger library at tag 'v1.2.3'
libs/logger#v1.2.3

// Add the helpers library to 'helpersLib' directory
libs/helpers:helpersLib

// Add the console app
apps/console

Usage

Running the Script

If Installed Locally

If you've installed the script as a local dependency, you can run it using npx:

npx git-setup-submodules

Alternatively, you can add a script to your package.json:

{
  "scripts": {
    "setup-submodules": "git-setup-submodules"
  }
}

Then run:

npm run setup-submodules

Using npx Directly

If you haven't installed the script locally, you can run it directly with npx:

npx git-setup-submodules

Script Workflow

1. Check for Existing .gitmodules

   • If .gitmodules exists, the script assumes submodules are already initialized and exits.

2. Read Configuration File

   • Parses .git-setup-submodules for submodule definitions.

3. Determine Remote URL Base

   • Retrieves the Git remote origin URL to construct full submodule URLs.

4. Process Each Submodule

   For each submodule in the configuration:

   • Access Verification
     • Uses git ls-remote to check if you have access to the repository.
   • Add Submodule
     • Executes git submodule add --force to add the submodule.
   • Set Branch or Tag
     • Configures the submodule to track the specified branch or tag.
   • Update Submodule
     • Pulls the latest changes with git pull.
   • Unstage Changes
     • Runs git restore --staged to unstage the submodule and .gitmodules.

5. Final Output

   • Displays a success message if submodules were added.
   • Displays an error message if no submodules were added.

Error Handling

• Missing Configuration File

  • The script exits with an error if .git-setup-submodules is not found.

• Git Repository Not Found

  • If the script cannot retrieve the remote origin URL, it exits with an error, indicating you may not be in a Git repository.

• Access Denied to Submodule

  • If access to a submodule repository is denied, the script logs an error and continues with the next submodule.

Logging

• Progress Messages

  • The script logs the setup process for each submodule, including paths and branches.

• Access Notifications

  • Informs you whether you have access to each submodule.

• Final Status

  • Displays a summary message upon completion.

Contributing

1. Fork the Repository

   • Create a fork to contribute changes.

2. Create a Feature Branch

   git checkout -b feature/your-feature-name

3. Commit Your Changes

   git commit -m "Add your feature"

4. Push to Your Fork

   git push origin feature/your-feature-name

5. Open a Pull Request

   • Submit a pull request to the main repository for review.

License

This project is licensed under the Apache 2.0.