How do I define the name of image built with docker-compose

Question

I'm using docker-compose to create my development environment. I want to build a specific image, but I don't know how to set a name for that image.

wildfly:
  build: /path/to/dir/Dockerfile
  container_name: wildfly_server
  ports:
   - 9990:9990
   - 80:8080
  environment:
   - MYSQL_HOST=mysql_server
   - MONGO_HOST=mongo_server
   - ELASTIC_HOST=elasticsearch_server
  volumes:
   - /Volumes/CaseSensitive/development/wildfly/deployments/:/opt/jboss/wildfly/standalone/deployments/
  links:
   - mysql:mysql_server
   - mongo:mongo_server
   - elasticsearch:elasticsearch_server

When I execute docker-compose everything is ok, but I get a random name for the new image. Is it possible to set a name to the build image?

Answer 1

For docker-compose version 2 file format, you can build and tag an image for one service and then use that same built image for another service.

For my case, I want to set up an elasticsearch cluster with 2 nodes, they both need to use the same image, but configured to run differently. I also want to build my own custom elasticsearch image from my own Dockerfile. So this is what I did (docker-compose.yml):

version: '2'

services:
  es-master:
    build: ./elasticsearch
    image: porter/elasticsearch
    ports:
      - "9200:9200"
    container_name: es_master

  es-node:
    image: porter/elasticsearch
    depends_on:
      - es-master
    ports:
      - "9200"
    command: elasticsearch --discovery.zen.ping.unicast.hosts=es_master

You can see that in the first service definition es-master, I use the build option to build an image from the Dockerfile in ./elasticsearch. I tag the image with the name porter/elasticsearch with the image option.
Then, I reference this built image in the es-node service definition with the image option, and also use a depends_on to make sure the other container es-master is built and run first.

Answer 2

As per docker-compose 1.6.0:

You can now specify both a build and an image key if you're using the new file format. docker-compose build will build the image and tag it with the name you've specified, while docker-compose pull will attempt to pull it.

So your docker-compose.yml would be

version: '2'
services:
  wildfly:
      build: /path/to/dir/Dockerfile
      image: wildfly_server
      ports:
       - 9990:9990
       - 80:8080

To update docker-compose

sudo pip install -U docker-compose==1.6.0

Answer 3

Option 1: Hinting default image name

The name of the image generated by docker-compose depends on the folder name by default but you can override it by using --project-name argument:

$ docker-compose --project-name foo build bar
$ docker images foo_bar

Option 2: Specifying image name

Once docker-compose 1.6.0 is out, you may specify build: and image: to have an explicit image name (see arulraj.net's answer).

Option 3: Create image from container

A third is to create an image from the container:

$ docker-compose up -d bar
$ docker commit $(docker-compose ps -q bar) foo_bar
$ docker-compose rm -f bar

Answer 4

Depending on your use case, you can use an image which has already been created and specify it's name in docker-compose.

We have a production use case where our CI server builds a named Docker image. (docker build -t <specific_image_name> .). Once the named image is specified, our docker-compose always builds off of the specific image. This allows a couple of different possibilities:

1- You can ensure that where ever you run your docker-compose from, you will always be using the latest version of that specific image.

2- You can specify multiple named images in your docker-compose file and let them be auto-wired through the previous build step.

So, if your image is already built, you can name the image with docker-compose. Remove build and specify image:

wildfly:
  image: my_custom_wildfly_image
  container_name: wildfly_server
  ports:
   - 9990:9990
   - 80:8080
  environment:
   - MYSQL_HOST=mysql_server
   - MONGO_HOST=mongo_server
   - ELASTIC_HOST=elasticsearch_server
  volumes:
   - /Volumes/CaseSensitive/development/wildfly/deployments/:/opt/jboss/wildfly/standalone/deployments/
  links:
   - mysql:mysql_server
   - mongo:mongo_server
   - elasticsearch:elasticsearch_server