Supported tags and respective Dockerfile links

• go2go-*, go2go-*-buster, go2go-buster,go2go, latest (Dockerfile)
• go2go-*-alpine, go2go-alpine, alpine (Dockerfile)

Docker Image with Go2 from dev.go2go branch

This is a nightly build of Golang Docker image from dev.go2go branch. I hope this build helps the community make more use of the new Go2 features.

dev.go2go branch

This branch contains a type checker and a translation tool for experimentation with generics in Go. This implements the generics design draft.

You can build this branch as usual. You can then use the new go2go tool. Write your generic code in a file with the extension .go2 instead of .go. Run it using go tool go2go run x.go2. There are some sample packages in cmd/go2go/testdata/go2path/src. You can see the full documentation for the tool by running go doc cmd/go2go.

The go2go tool will look for .go2 files using the environment variable GO2PATH. You can find some useful packages that you might want to experiment with by setting GO2PATH=$GOROOT/src/cmd/go2go/testdata/go2path.

If you find bugs in the updated type checker or in the translation tool, they should be filed in the standard Go issue tracker. Please start the issue title with cmd/go2go. Note that the issue tracker should only be used for reporting bugs in the tools, not for discussion of changes to the language.

Unlike typical dev branches, we do not intend any eventual merge of this code into the master branch. We will update it for bug fixes and change to the generic design draft. If a generics language proposal is accepted, it will be implemented in the standard compiler, not via a translation tool. The necessary changes to the go/* packages (go/ast, go/parser, and so forth) may re-use code from this prototype but will follow the usual code review process.

How to use this image

Note: /go is world-writable to allow flexibility in the user which runs the container (for example, in a container started with --user 1000:1000, running go get github.com/example/... will succeed). While the 777 directory would be insecure on a regular host setup, there are not typically other processes or users inside the container, so this is equivilant to 700 for Docker usage, but allowing for --user flexibility.

Start a Go instance in your app

The most straightforward way to use this image is to use a Go container as both the build and runtime environment. In your Dockerfile, writing something along the lines of the following will compile and run your project:

FROM levonet/golang:go2go

WORKDIR /go/src/app
COPY . .

RUN go get -d -v ./...
RUN go install -v ./...

CMD ["app"]

You can then build and run the Docker image:

$ docker build -t my-golang-app .
$ docker run -it --rm --name my-running-app my-golang-app

Compile your app inside the Docker container

There may be occasions where it is not appropriate to run your app inside a container. To compile, but not run your app inside the Docker instance, you can write something like:

$ docker run --rm -v "$PWD":/go/src/myapp -w /go/src/myapp levonet/golang:go2go go build -v

Or compile .go2 source files:

$ docker run --rm -v "$PWD":/go/src/myapp -w /go/src/myapp levonet/golang:go2go go tool go2go build

Image Variants

The levonet/golang images come in many flavors, each designed for a specific use case.

levonet/golang:<version>

This is the defacto image. If you are unsure about what your needs are, you probably want to use this one. It is designed to be used both as a throw away container (mount your source code and start the container to start your app), as well as the base to build other images off of.

Some of these tags may have names like buster in them. These are the suite code names for releases of Debian and indicate which release the image is based on. If your image needs to install any additional packages beyond what comes with the image, you'll likely want to specify one of these explicitly to minimize breakage when there are new releases of Debian.

levonet/golang:<version>-alpine

This image is based on the popular Alpine Linux project, available in the alpine official image. Alpine Linux is much smaller than most distribution base images (~5MB), and thus leads to much slimmer images in general.

This variant is highly experimental, and not officially supported by the Go project (see golang/go#19938 for details).

The main caveat to note is that it does use musl libc instead of glibc and friends, which can lead to unexpected behavior. See this Hacker News comment thread for more discussion of the issues that might arise and some pro/con comparisons of using Alpine-based images.

To minimize image size, additional related tools (such as git, gcc, or bash) are not included in Alpine-based images. Using this image as a base, add the things you need in your own Dockerfile (see the alpine image description for examples of how to install packages if you are unfamiliar). See also docker-library/golang#250 (comment) for a longer explanation.

License

View license information for the software contained in this image or license information for the Golang Dockerfile.

As with all Docker images, these likely also contain other software which may be under other licenses (such as Bash, etc from the base distribution, along with any direct or indirect dependencies of the primary software being contained).

Some additional license information which was able to be auto-detected might be found in the repo-info repository's golang/ directory.

As for any pre-built image usage, it is the image user's responsibility to ensure that any use of this image complies with any relevant licenses for all software contained within.