Bitbucket to GitHub Migration Script

migrate.sh

#! /bin/bash

# - Does not work with empty Bitbucket repositories
# - Does not work if repo description contains control characters, e.g. '\r'

ALL_REPOS=$@

# Check if any arguments were provided
if [[ $# -eq 0 ]]; then
    echo "No repository name(s) provided!" 1>&2
    exit 1
fi

# Define ANSI color codes
CLEAR='\033[0m'
RED='\033[00;31m'
GREEN='\033[00;32m'
YELLOW='\033[00;33m'
BLUE='\033[00;34m'

transfer_repo () {
    REPO_NAME=$1

    # Set up working directory...
    WORK_DIR="/tmp/repo-migrations/${REPO_NAME}"
    rm -rf $WORK_DIR
    mkdir -p $WORK_DIR

    # Get repo info from Bitbucket's API...
    BB_REPO_JSON=$(curl --request GET -s \
        --user $BITBUCKET_AUTH \
        --url "https://api.bitbucket.org/2.0/repositories/$REPO_NAME" \
        --header 'Accept: application/json')

    # Parse out description and trunk name...
    REPO_DESC=$(echo $BB_REPO_JSON | jq -r '.description' | tr -d '\r') || ''
    TRUNK_NAME=$(echo $BB_REPO_JSON | jq -r '.mainbranch.name') || 'main'

    # Clone the repo...
    echo -e "[${BLUE}$REPO_NAME${CLEAR}] ${GREEN}Cloning: ${YELLOW}git@bitbucket.org:$REPO_NAME.git${GREEN} to ${YELLOW}$WORK_DIR${CLEAR}"
    git clone --bare git@bitbucket.org:$REPO_NAME.git $WORK_DIR --quiet
    cd $WORK_DIR

    # Perform migration...
    create_github_repo
    rename_master_to_main
    push_to_github
}

create_github_repo () {
    if [ -n "$REPO_DESC" ]; then
        echo -e "[${BLUE}$REPO_NAME${CLEAR}] ${YELLOW}Name:${CLEAR} $REPO_NAME"
        echo -e "[${BLUE}$REPO_NAME${CLEAR}] ${YELLOW}Description:${CLEAR} $REPO_DESC"
        echo -e -n "[${BLUE}$REPO_NAME${CLEAR}] ${GREEN}Creating GitHub repository... ${CLEAR}"

        CREATE_OUTPUT=$(gh repo create $REPO_NAME --private --description="$REPO_DESC" 2>&1)

    else
        echo -e "[${BLUE}$REPO_NAME${CLEAR}] ${YELLOW}Name:${CLEAR} $REPO_NAME"
        echo -e "[${BLUE}$REPO_NAME${CLEAR}] ${YELLOW}Description:${CLEAR} (none)"
        echo -e -n "[${BLUE}$REPO_NAME${CLEAR}] ${GREEN}Creating GitHub repository... ${CLEAR}"

        CREATE_OUTPUT=$(gh repo create $REPO_NAME --private 2>&1)
    fi

    if [ $? -eq 0 ]; then
        echo -e "${GREEN}Done!${CLEAR}"
    elif [[ $CREATE_OUTPUT == *"Name already exists"* ]]; then
        echo -e "${YELLOW}Already exists!${CLEAR}" 1>&2
        echo -e "[${BLUE}$REPO_NAME${CLEAR}] ${YELLOW}Could not create GitHub repository, it already exists.${CLEAR}" 1>&2
    else
        echo -e "${RED}Failed!${CLEAR}" 1>&2
        echo -e "[${BLUE}$REPO_NAME${CLEAR}] ${RED}Could not create GitHub repository for some unknown reason.${CLEAR}" 1>&2

        exit 1
    fi
}

rename_master_to_main () {
    # Rename trunk if needed
    if [[ $TRUNK_NAME == "master" ]]; then
        echo -e -n "[${BLUE}$REPO_NAME${CLEAR}] Renaming master to main... "
        git branch -m master main --quiet
        if [ $? -eq 0 ]; then
            echo -e "${GREEN}Done!${CLEAR}"
        else
            echo -e "${RED}Failed!${CLEAR}" 1>&2
            echo -e "[${BLUE}$REPO_NAME${CLEAR}] ${RED}Could not rename master branch to main automatically, please change manually using GitHub web UI.${CLEAR}" 1>&2

            exit 1
        fi
    fi
}

push_to_github () {
    # Push mirror to GitHub
    echo -e -n "[${BLUE}$REPO_NAME${CLEAR}] Pushing to GitHub... "
    git push --mirror https://github.com/$REPO_NAME.git --quiet

    if [ $? -eq 0 ]; then
        echo -e "${GREEN}Done!${CLEAR}"
    else
        echo -e "${RED}Failed!${CLEAR}"
        echo -e "${RED}ERROR: Could not pushed changed repository to GitHub.${CLEAR}" 1>&2

        exit 1
    fi
}

for REPO in ${ALL_REPOS[@]}
do
    transfer_repo $REPO
done