baktainer

Easily backup databases running in docker containers.

Features

• Backup MySQL, PostgreSQL, MongoDB, and SQLite databases
• Run on a schedule using cron expressions
• Backup databases running in docker containers
• Define which databases to backup using docker labels

Installation

⚠️ Security Notice: Baktainer requires Docker socket access which grants significant privileges. Please review SECURITY.md for important security considerations and recommended mitigations.

services:
  baktainer:
    image: jamez001/baktainer:latest
    container_name: baktainer
    restart: unless-stopped
    volumes:
      - ./backups:/backups
      - /var/run/docker.sock:/var/run/docker.sock
    environment:
      - BT_CRON="0 0 * * *" # Backup every day at midnight
      - "BT_DOCKER_URL=unix:///var/run/docker.sock" 
      - BT_THREADS=4
      - BT_LOG_LEVEL=info
      # Enable if using SSL over tcp
      #- BT_SSL = true
      #- BT_CA
      #- BT_CERT
      #- BT_KEY    

For enhanced security, consider using a Docker socket proxy. See SECURITY.md for detailed security recommendations.

Environment Variables

Variable	Description	Default
BT_CRON	Cron expression for scheduling backups	0 0 * * *
BT_THREADS	Number of threads to use for backups	4
BT_LOG_LEVEL	Log level (debug, info, warn, error)	info
BT_COMPRESS	Enable gzip compression for backups	true
BT_SSL	Enable SSL for docker connection	false
BT_CA	Path to CA certificate	none
BT_CERT	Path to client certificate	none
BT_KEY	Path to client key	none
BT_DOCKER_URL	Docker URL	unix:///var/run/docker.sock

Usage

Add labels to your docker containers to specify which databases to backup.

services:
  db:
    image: postgres:17
    container_name: my-db
    restart: unless-stopped
    volumes:
    - db:/var/lib/postgresql/data
    environment:
      POSTGRES_DB: "${DB_BASE:-database}"
      POSTGRES_USER: "${DB_USER:-user}"
      POSTGRES_PASSWORD: "${DB_PASSWORD:-StrongPassword}"
    labels:
      - baktainer.backup=true
      - baktainer.db.engine=postgres
      - baktainer.db.name=my-db
      - baktainer.db.user=user
      - baktainer.db.password=StrongPassword
      - baktainer.name="MyApp"

Possible Values for Labels

Label	Description
baktainer.backup	Set to true to enable backup for this container
baktainer.db.engine	Database engine (mysql, postgres, mongodb, sqlite)
baktainer.db.name	Name of the database to backup
baktainer.db.user	Username for the database
baktainer.db.password	Password for the database
baktainer.name	Name of the application (optional). Determines name of sql dump file.
baktainer.compress	Enable gzip compression for this container's backups (true/false). Overrides BT_COMPRESS.

Backup Files

The backup files will be stored in the directory specified by the BT_BACKUP_DIR environment variable. The files will be named according to the following format:

/backups/<date>/<db_name>-<timestamp>.sql.gz

Where <date> is the date of the backup ('YY-MM-DD' format) <db_name> is the name provided by baktainer.name, or the name of the database, <timestamp> is the unix timestamp of the backup.

By default, backups are compressed with gzip. To disable compression, set BT_COMPRESS=false or add baktainer.compress=false label to specific containers.

Testing

The project includes comprehensive test coverage with both unit and integration tests.

Running Tests

# Run all tests
cd app && bundle exec rspec

# Run tests with coverage report
cd app && COVERAGE=true bundle exec rspec

# Run only unit tests
cd app && bundle exec rspec spec/unit/

# Run only integration tests (requires Docker)
cd app && bundle exec rspec spec/integration/

Test Coverage

• Line Coverage: 94.94% (150/158 lines)
• Branch Coverage: 71.11% (32/45 branches)
• Tests cover all database engines, container discovery, error handling, and backup workflows
• Integration tests validate full backup operations with real Docker containers

Test Commands

# Quick unit tests
bin/test

# All tests with coverage
bin/test --all --coverage

# Integration tests with setup/cleanup
bin/test --integration --setup --cleanup

Roadmap

• Add support for SQLite backups
• Add support for MongoDB backups
• Add support for MySQL backups
• Add support for PostgreSQL backups
• Add support for cron scheduling
• Add support for Docker labels to specify which databases to backup
• Add support for Docker socket
• Add support for Docker API over TCP
• Add support for Docker API over SSL
• Add support for Docker API over HTTP
• Add support for Docker API over HTTPS
• Add support for Docker API over Unix socket
• Add comprehensive test coverage (94.94% line coverage)
• Add individual hook for completed backups
• Add hook for fullly completed backups
• Optionally limit time for each backup