docker-compose-mixer

Package which allow to run docker-compose with several docker-compose.yml files

Installation (only for UNIX & MacOS)

• Download bin file sudo wget https://github.com/paunin/docker-compose-mixer/blob/master/dist/dc-mixer?raw=true -O /usr/local/bin/dc-mixer
• Make it executable sudo chmod +x /usr/local/bin/dc-mixer
• Run it as console command dc-mixer from directory with docker-compose-mixer.yml file

Internal flow

• get containers definitions
• change services names
• resolving services names as atomic operation with:
  • remove ignored services (all from ignores section of config)
  • remove links to ignored services
• resolve paths
• resolving ports conflicts (to avoid binding the same ports from different files)
• apply overrides
• add master services

Configuration and syntax

By default Mixer uses file in the same directory with name docker-compose-mixer.yml

Includes

includes:
  proja: projectA/docker-compose.yml
  projb: projectB/docker-compose.yml
...

Based on this configuration all services from projectA in result file will change names and will have prefix proja That means prefixes should contain only allowed symbols according docker-compose syntax.

If projectA/docker-compose.yml contains code:

mysql:
  image: mysql:latest

pgsql:
  image: postgres:latest

php:
  build: images/php
  links:
    - pgsql
    - mysql:database
  volumes_from:
    - pgsql

...and projectB/docker-compose.yml contains code:

pgsql:
  build: images/pgsql

In result file you will see configuration:

projamysql:
  image: mysql:latest

projapgsql:
  image: postgres:latest

projaphp:
  build: projectA/images/php
  links:
    - projapgsql:pgsql
    - projamysql:database
  volumes_from:
    - projapgsql

projbpgsql:
  build: projectB/images/pgsql

That means Mixer added prefix to services names and solved problems in names conflicts with using aliases. Resolving names conflicts is available for:

• links
• volumes_from
• container_name (if only container name defined it will be changed with prefix after processing)
• extends.service (if only extends.file not defined)

Also in example above you can see that Mixer changed paths to build: Resolving paths is available for:

• build
• volumes
• env_file
• extends

Overrides

...
overrides:
  projaphp:
    ports:
      - 80:80
    links:
      - projbpgsql:pgsql

  projbphp:
    ports:
      - 81:80
...

In section overrides you can define values to merge in result file.

NOTES:

• Ports you defined in overrides will be in result file without changes. Mixer will not try to solve conflicts in overrides.
• To redefine values for paths (e.g. build, voluems) be sure paths will be related to docker-compose-mixer.yml file
• If you want redefine attribute which should contain array, keep in mind: your array will be in result file without any merging to original value (e.g. ports, links)

Master services

If you want to link services from two(or more) different docker-compose.yml, you have to define it in overrides or create another service where you will define links. In section master_services you must define normal

...
master_services:
  php:
    ports:
      8080:80
    links:
      - projbpgsql:pgsql
      - projamysql:mysql
    volumes_from:
      - projaphp

NOTES:

• Any services in master_services section will be in result file without any changes.
• You have to use names of services with prefixes because of... @see case above ;)

Ignores

...
ignores:
  - projbpgsql

This section will remove services from result file and will check if any service linked with it and clean it as well. Cleaning available for same services where resolving names conflicts available.

If services uses for extend directive, child service will be ignored as well

Result

File docker-compose.yml will be result of Mixer job. You can put that file in .gitignore if you will use Mixer every build.

After run of Mixer you can work with docker-compose.yml file like you do with any docker-compose configurations.

Examples

More examples you can find in examples directory.

Copyright

• Dmitriy Paunin [email protected]