goreleaser/docs/130-docker.md

title
Docker

Since v0.31.0, GoReleaser supports building and pushing Docker images.

How it works

You can declare multiple Docker images. They will be matched against the binaries generated by your builds section.

If you have only one build setup, the configuration is as easy as adding the name of your image to your .goreleaser.yml file:

dockers:
  - image: user/repo

You also need to create a Dockerfile in your project's root folder:

FROM scratch
COPY mybin /
ENTRYPOINT ["/mybin"]

This configuration will build and push a Docker image named user/repo:tagname.

Customization

Of course, you can customize a lot of things:

# .goreleaser.yml
dockers:
  # You can have multiple Docker images.
  -
    # GOOS of the built binary that should be used.
    goos: linux
    # GOARCH of the built binary that should be used.
    goarch: amd64
    # GOARM of the built binary that should be used.
    goarm: ''
    # Name of the built binary that should be used.
    binary: mybinary
    # Docker image name.
    image: myuser/myimage
    # Path to the Dockerfile (from the project root).
    dockerfile: Dockerfile
    # Template of the docker tag. Defaults to `{{ .Version }}`. Other allowed
    # fields are `.Tag`, `.Major`, `.Minor` and `.Patch` and
    # `.Env.VARIABLE_NAME`.
    tag_templates:
    - "{{ .Tag }}"
    - "{{ .Tag }}-{{ .Env.GO_VERSION }}"
    - "v{{ .Major }}"
    - latest
    # If your Dockerfile copies files other than the binary itself,
    # you should list them here as well.
    extra_files:
    - config.yml

These settings should allow you to generate multiple Docker images, for example, using multiple FROM statements, as well as generate one image for each binary in your project.

Passing environment variables to tag_template

You can do that by using {{ .Env.VARIABLE_NAME }} in the template, for example:

dockers:
  -
    tag_template: "{{ .Tag }}-{{ .Env.GOVERSION_NR }}"

Then you can run:

GOVERSION_NR=$(go version | awk '{print $3}') goreleaser

Keeping docker images updated for current major

Some users might want to when version to push docker tags :v1, :v1.6, :v1.6.4 and :latest when v1.6.4 (for example) is built. That can be accomplished by using multiple tag_templates:

# .goreleaser.yml
dockers:
  -
    binary: mybinary
    image: myuser/myimage
    tag_templates:
    - "{{ .Tag }}"
    - "v{{ .Major }}"
    - "v{{ .Major }}.{{ .Minor }}"
    - latest

This will build and publish the following images:

• myuser/myimage:v1.6.4
• myuser/myimage:v1
• myuser/myimage:v1.6
• myuser/myimage:latest

Hope this feature serves you well!

More info:

• #461
• #505