Mirror any repo into a private repository on your GitHub account

mirror-repo.sh

#!/bin/bash

#===============================================================================
# mirror-repo.sh
#
# Clones a source repository and mirrors it to a new private repository on
# your GitHub account.
#
# Usage:
#   ./mirror-repo.sh <source_repository_url>
#
# Example:
#   ./mirror-repo.sh https://github.com/git/git.git
#
# Dependencies:
#   - git
#   - GitHub CLI (gh)
#===============================================================================

set -e
set -o pipefail

if [[ -z "$1" ]]; then
    echo "❌ Error: No source repository URL provided."
    echo "Usage: $0 <source_repository_url>"
    exit 1
fi

SOURCE_REPO_URL="$1"
DEST_REPO_NAME=$(basename -s .git "$SOURCE_REPO_URL")
BARE_CLONE_DIR="${DEST_REPO_NAME}.git"

if ! command -v git &> /dev/null; then
    echo "❌ Error: 'git' is not installed. Please install it and ensure it's in your PATH."
    exit 1
fi

if ! command -v gh &> /dev/null; then
    echo "❌ Error: GitHub CLI ('gh') is not installed. Please install it to continue."
    exit 1
fi

if ! gh auth status &> /dev/null; then
    echo "❌ Error: You are not logged into the GitHub CLI. Please run 'gh auth login' first."
    exit 1
fi

echo


echo "🔎 Checking if repository '$DEST_REPO_NAME' already exists on your GitHub account..."
if gh repo view "$DEST_REPO_NAME" &>/dev/null; then
    echo "❌ Error: A repository named '$DEST_REPO_NAME' already exists on your GitHub account."
    echo "Please choose a different name, or delete the existing repository and try again."
    exit 1
fi
echo "✅ Repo name $DEST_REPO_NAME available. Proceeding..."
echo

TEMP_DIR=$(mktemp -d)
trap 'rm -rf "$TEMP_DIR"' EXIT

cd "$TEMP_DIR"

echo "📂 Cloning '$SOURCE_REPO_URL' as a bare repository..."
git clone --bare "$SOURCE_REPO_URL" "$BARE_CLONE_DIR"
echo "✅ Clone complete."

cd "$BARE_CLONE_DIR"

echo "🔧 Removing original 'origin' remote to prevent conflict..."
git remote remove origin
echo "🚀 Creating private repository '$DEST_REPO_NAME' on GitHub and pushing the mirror..."
gh repo create "$DEST_REPO_NAME" --private --description "Private mirror of $SOURCE_REPO_URL" --source=. --push

echo "🎉 Success! Your private mirror has been created on GitHub."