Cloner

Easily clone your production Mongoid or PostgreSQL / MySQL database and files for local development or staging area.

Uses rsync and database-specific default dump/restore tools (pg_dump/pg_restore, mysqldump/mysql, mongodump/mongorestore)

Installation

Add this line to your application's Gemfile:

gem 'cloner'

And then execute:

$ bundle

Or install it yourself as:

$ gem install cloner

Usage

For generate cloner base template, run:

bundle exec rails generate cloner

This is create lib/tasks/dl.thor file with following content:

require 'cloner'

class Dl < Cloner::Base
  no_commands do
    def rails_path
      File.expand_path("../../../config/environment", __FILE__)
    end
    def ssh_host
      'hottea.ru'
    end
    def ssh_user
      'tea'
    end
    def remote_dump_path
      '/data/tea/dump'
    end
    def remote_app_path
      "/data/tea/app/current"
    end
  end

  desc "download", "clone files and DB from production"
  def download
    load_env
    clone_db
    rsync_public("ckeditor_assets")
    rsync_public("uploads")
  end
end

Adjust it to your project and deployment.

Run it:

thor dl

If you generate extended cloner template as: rails g cloner -e, you can run thor dl with additional parameters, for example:

bundle exec thor dl -D # For skip clone database
bundle exec thor dl -F # For skip clone files

For details see help:

bundle exec thor help dl:download

Usage:
  thor dl:download

Options:
      [--from=FROM]                            # stage name where cloner get data
                                               # Default: production
  -D, [--skip-database], [--no-skip-database]  # skip clone database
  -F, [--skip-files], [--no-skip-files]        # skip clone files

clone files and DB from production

Additional

All functions from cloner/internal.rb can be overriden, for example:

def verbose?
  false
end
def env_from
  'production'
end
def ssh_opts
  {}
end

Docker Compose Support

Cloner now supports Docker Compose for both local and remote database operations. This is useful when your databases run inside Docker containers.

Generating Docker Compose Template

To generate a template with Docker Compose examples:

bundle exec rails generate cloner -d

Configuration

Add these methods to your dl.thor file to enable Docker Compose:

# For remote Docker Compose
def remote_docker_compose?
  true
end

def remote_docker_compose_service
  'db'  # Your database service name in compose.yml
end

def remote_docker_compose_path
  remote_app_path  # Path where compose.yml is located
end

# Optional: Override compose file name (default is 'compose.yml')
def remote_docker_compose_file
  'docker-compose.yml'  # Use if your file is named differently
end

# For local Docker Compose
def local_docker_compose?
  true
end

def local_docker_compose_service
  'db'  # Your local database service name
end

def local_docker_compose_path
  Rails.root.to_s  # Path where your local compose.yml is located
end

# Optional: Override compose file name for local (default is 'compose.yml')
def local_docker_compose_file
  'docker-compose.yml'  # Use if your file is named differently
end

# Optional: Override local database config (reads from local .env by default)
def local_db_config
  {
    adapter: 'postgresql',
    host: read_local_env('DB_HOST') || 'localhost',
    port: read_local_env('DB_PORT') || '5432',
    database: read_local_env('DB_NAME'),
    username: read_local_env('DB_USER'),
    password: read_local_env('DB_PASSWORD')
  }.stringify_keys
end

PostgreSQL with Docker Compose Example

class Dl < Cloner::Base
  no_commands do
    def ssh_host
      'production.example.com'
    end
    
    def ssh_user
      'deploy'
    end
    
    def remote_app_path
      '/home/deploy/myapp'
    end
    
    def remote_dump_path
      "#{remote_app_path}/tmp_dump"
    end
    
    # Enable Docker Compose for remote
    def remote_docker_compose?
      true
    end
    
    def remote_docker_compose_service
      'postgres'
    end
    
    # Override to read credentials from .env file
    def read_ar_r_conf
      # Read from remote .env file
      env_content = ""
      do_ssh do |ssh|
        env_content = ssh.exec!("cat #{e remote_app_path}/.env")
      end
      
      # Parse .env content
      env_vars = {}
      env_content.each_line do |line|
        next if line.strip.empty? || line.strip.start_with?('#')
        key, value = line.strip.split('=', 2)
        next unless key && value
        value = value.gsub(/^["']|["']$/, '')
        env_vars[key] = value
      end
      
      {
        adapter: "postgresql",
        host: env_vars['DB_HOST'] || 'postgres',
        database: env_vars['DB_NAME'],
        username: env_vars['DB_USER'],
        password: env_vars['DB_PASSWORD']
      }.stringify_keys
    end
    
    # Enable Docker Compose for local
    def local_docker_compose?
      true
    end
    
    def local_docker_compose_service
      'db'
    end
  end
  
  desc "download", "clone DB from production"
  def download
    load_env
    clone_db
  end
end

How It Works

When Docker Compose is enabled:

1. Remote operations: Database dump commands are wrapped with docker compose exec on the remote server
2. Local operations: Database restore commands pipe data into docker compose exec -T locally
3. Automatic command wrapping: The gem automatically detects and wraps database commands appropriately

Supported Databases

Docker Compose support is available for:

• PostgreSQL
• MySQL

Changelog

0.14.0

• Add Docker Compose support for local and remote database operations
• Add Docker Compose generator template with -d option
• Support automatic command wrapping for PostgreSQL and MySQL when using Docker Compose
• Add helper methods for Docker Compose configuration
• Default compose file name is now 'compose.yml' (configurable via docker_compose_file methods)
• Add local_db_config and remote_db_config methods for customizing database configurations
• Support reading from .env files for both local and remote environments
• Replace direct usage of ar_conf and ar_r_conf with configurable local_db_config and remote_db_config

0.10.0

• Support rails 6 multi database activerecord apps via option

def multi_db?
  true
end
def clone_databases
  ["primary", "gis"]
  # nil - clone all databases
end

• Backwards incompatible change:

Changed default dump file name to cloner.bak in postgresql to make it same, and to allow to override it and multiple files.

0.9.0

• Add option to rsync to allow sync one file (thx @AnatolyShirykalov)
• Add env_database to allow overriding database env (thx @Yarroo)

0.8.0

• Change default rsync flags - -z to -zz to support newer versions of rsync
• Allow overriding rsync flags via rsync_flags and rsync_compression

0.7.0

• Add thor file generators

0.6.0

• Support MySQL

Contributing

1. Fork it ( https://github.com/[my-github-username]/cloner/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request