Script for GitLab to Github Repository Migration

account.yaml

gitlab_username: <your-gitlab-username>
gitlab_access_token: <your-gitlab-access-token>
github_username: <your-github-username>
github_access_token: <your-github-access-token>
github_repo_owner: <your-github-repo-owner username or organization name>

gitlab2github_migrate.py

# Pre-requisites:
# 1. Install GitHub CLI: https://cli.github.com/
# 2. Install Git: https://git-scm.com/
# 3. Install PyYAML: pip3 install pyyaml
# 4. Run 'gh auth login' to login to GitHub CLI
# 5. Prepare the configuration file with the following fields:
#    gitlab_username: <GitLab username>
#    gitlab_access_token: <GitLab access token>
#    github_username: <GitHub username>
#    github_access_token: <GitHub access token>
#    github_repo_owner: <GitHub repository owner>
# 6. Get ready the GitLab project ID and GitHub repository name
# 7. Get ready the GitLab and Github access tokens
# 8. Run the script with the following command:
#    python gitlab2github_migrate.py <config_file> <gitlab_project_id> <github_repo_name>
import subprocess
import yaml
import sys
import os

root_dir = os.path.dirname(os.path.realpath(__file__))


def is_github_cli_logged_in():
    try:
        result = subprocess.run(
            ["gh", "auth", "status"], capture_output=True, text=True
        )
        if "Logged in to github.com" in result.stdout:
            return True
        else:
            return False
    except FileNotFoundError:
        print("GitHub CLI is not installed.")
        return False


def load_config(config_file):
    with open(config_file, "r") as file:
        config = yaml.safe_load(file)

    return config


def check_config(config):
    required_fields = [
        "gitlab_username",
        "gitlab_access_token",
        "github_username",
        "github_access_token",
        "github_repo_owner",
    ]

    result = True
    for field in required_fields:
        if field not in config:
            print(f"Configuration file is missing {field}")
            result = False

    return result


def try_command(command):
    try:
        result = subprocess.run(
            command,
            capture_output=False,
            text=True,
        )
        # if "Error" in result.stdout:
        #     return False
        # else:
        return True
    except FileNotFoundError:
        print("Command not found.")
        return False


def get_github_repo_url(config, github_repo_name):
    github_repo_owner = config.get("github_repo_owner")
    github_access_token = config.get("github_access_token")

    return f"https://{github_access_token}@github.com/{github_repo_owner}/{github_repo_name}.git"


def clone_repo_to_github(config, gitlab_project_id, github_repo_name):
    folder_name = gitlab_project_id.split("/")[-1] + ".git"
    full_folder_name = os.path.join(root_dir, folder_name)
    github_repo_url = get_github_repo_url(config, github_repo_name)

    print(f"folder_name: {folder_name}")
    print(f"github_repo_url: {github_repo_url}")

    try:
        os.chdir(full_folder_name)
    except FileNotFoundError:
        print(f"Directory {folder_name} not found.")
        return False

    # try_command(["pwd"])

    if not try_command(["git", "remote", "remove", "origin"]):
        print(f"Error removing remote origin")
        return False

    if not try_command(["git", "remote", "add", "origin", github_repo_url]):
        print(f"Error adding remote origin")
        return False

    if not try_command(["git", "push", "--mirror", "origin"]):
        print(f"Error pushing to remote origin")
        return False

    try:
        os.chdir(root_dir)
    except FileNotFoundError:
        print(f"Directory {root_dir} not found.")
        # return Falseif

    # try_command(["pwd"])
    try:
        os.system(f"rm -rf {folder_name}")
    except FileNotFoundError:
        print(f"Error removing directory {folder_name}")
        # return False

    print(f"Repository {folder_name} migrated to GitHub repository {github_repo_name}")


def get_gitlab_repo_url(config, gitlab_project_id):
    gitlab_username = config.get("gitlab_username")
    gitlab_access_token = config.get("gitlab_access_token")

    return f"https://{gitlab_username}:{gitlab_access_token}@gitlab.com/{gitlab_project_id}.git"


def download_gitlab_repo(config, gitlab_project_id):
    repo_url = get_gitlab_repo_url(config, gitlab_project_id)
    print(f"repo_url: {repo_url}")
    try:
        result = subprocess.run(
            [
                "git",
                "clone",
                "--bare",
                repo_url,
            ],
            capture_output=True,
            text=True,
        )
        if "Error" in result.stdout:
            print(f"Error cloning GitLab repository {repo_url}")
            return False
        else:
            print(f"GitLab repository {repo_url} cloned successfully")
            return True
    except FileNotFoundError:
        print("Git is not installed.")
        return False


def create_github_repo(config, repo_name):
    owner = config.get("github_repo_owner")
    if owner == None:
        repo_location = repo_name
    else:
        repo_location = owner + "/" + repo_name

    try:
        result = subprocess.run(
            ["gh", "repo", "create", repo_location, "--private", "--confirm"],
            capture_output=True,
            text=True,
        )
        if "Error" in result.stdout:
            print(f"Error creating GitHub repository {repo_location}")
            return False
        else:
            print(f"GitHub repository {repo_location} created successfully")
            return True
    except FileNotFoundError:
        print("GitHub CLI is not installed.")
        return False


# Example usage
if __name__ == "__main__":
    if len(sys.argv) != 4:
        print(
            "Usage: python gitlab2github_migrate.py <config_file> <gitlab_project_id> <github_repo_name>"
        )
        exit(1)

    config_file = sys.argv[1]
    gitlab_project_id = sys.argv[2]
    github_repo_name = sys.argv[3]
    config = load_config(config_file)

    if not check_config(config):
        exit(1)

    if not is_github_cli_logged_in():
        print("GitHub CLI is not logged in. Please run 'gh auth login'")
        exit(1)

    print("Migration Config")
    print(yaml.dump(config, default_flow_style=False))
    

# Example usage
if __name__ == "__main__":

    # Output
    print("Begin migration...")

    print("Create GitHub repository")
    create_github_repo(config, github_repo_name)
    print(get_gitlab_repo_url(config, gitlab_project_id))
    result = download_gitlab_repo(config, gitlab_project_id)
    if not result:
        print("Error downloading GitLab repository")
        exit(1)

    clone_repo_to_github(config, gitlab_project_id, github_repo_name)

    print("Migration complete.")