How can I make docker-compose build an image from a remote git repository?

Are you running version 1.5.2? It looks like this was actually recently added in https://github.com/docker/compose/pull/2430. Try upgrading.

Example:

---version: '2'services:  redis:    image: "redis:3.2.3"    hostname: redis  redis-commander:    build: https://github.com/joeferner/redis-commander.git    command: --redis-host redis    links:      - "redis:redis"    ports:      - 8081

Tested with:

$ docker-compose -vdocker-compose version 1.11.2, build dfed245

The file tests/unit/config/config_test.py shows:

def test_valid_url_in_build_path(self):    valid_urls = [        'git://github.com/docker/docker',        'git@github.com:docker/docker.git',        'git@bitbucket.org:atlassianlabs/atlassian-docker.git',        'https://github.com/docker/docker.git',        'http://github.com/docker/docker.git',        'github.com/docker/docker.git',    ]

This is confirmed with compose/config/config.py#L79-L85:

DOCKER_VALID_URL_PREFIXES = (    'http://',    'https://',    'git://',    'github.com/',    'git@',)

I think there is a better way to do this now!

If you want to use a Dockerfile that's located inside the repo and the repo is public, your best guess is to use the raw file.

E.g. for the file Dockerfile_dev inside https://github.com/certbot/certbot, you could use https://raw.githubusercontent.com/certbot/certbot/master/Dockerfile-dev

Then in docker-compose, add it like this in order to use the Dockerfile from the remote location.

certbot_dev:  image: certbot-dev  build: https://raw.githubusercontent.com/certbot/certbot/master/Dockerfile-dev

You can find the raw link, when you click on a button called 'Raw' inside the file preview: https://github.com/certbot/certbot/blob/master/Dockerfile-dev