Docker-compose 指定配置文件

Question

I'm new to docker and now I want to use docker-compose . I would like to provide the docker-compose.yml script the config file with host/port, maybe credentials and other cassandra configuration.

DockerHub link.

How to specify it in the compose script:

cassandra:
  image: bitnami/cassandra:latest

Answer 1

You can do it using Docker compose environment variables( https://docs.docker.com/compose/environment-variables/#substituting-environment-variables-in-compose-files ). You can also specify a separate environment file with environment variables.

Answer 2

Apparently, including a file outside of the scope of the image build, such as a config file, has been a major point of discussion (and perhaps some tension) between the community and the folks at Docker. A lot of the developers in that linked issue recommended adding config files in a folder as a volume (unfortunately, you cannot add an individual file).

It would look something like:

volumes:
  - ./config_folder:./config_folder

Where config_folder would be at the root of your project, at the same level as the Dockerfile.

Answer 3

If Docker compose environment cannot solved your problem, you should create a new image from the original image with COPY to override the file.

Dockerfile:

From orginal_image:xxx
COPY local_conffile in_image_dir/conf_dir/