Changing environment

All service versions are stored and taken from variables, independently configurable for each environment. For global changes in services (enable, disable, add), you should edit docker-compose.yml.

For specific environment edits, like port mapping, file sharing etc, you should not edit docker-compose.yml, and work on environment specific overwrites, eg: docker-compose.local.yml.

Two types of variable configuration is used:

ARG

These parameters are set and used for building application container, changed in the .env file, the default values set in Dockerfile and persisted via ENV with the same name.

When you change any ARG parameter, you need to rebuild container, test it, and push changes to the repo.

ENV

This set of parameters are used in application and service runtime, couple of them are set in .env, and the rest in the .application.

The .application contains:

• Magento admin credentials

• Magento configurations, i.e: base url, mode

• MySQL credentials

The .env contains:

• Open ports

• Service versions

• Project tag

When those settings are changed, you need to recreate the needed container.

Reference

• https://vsupalov.com/docker-arg-env-variable-guide/ - complete guide and description about ARG/ENV usage in docker/docker-compose
• https://docs.docker.com/compose/compose-file/ - full docker-compose.yml reference
• https://docs.docker.com/compose/env-file/ - docker-compose .env usage