Supported tags and respective
Where to file issues:
the Docker Community
Supported Docker versions:
the latest release (down to 1.6 on a best-effort basis)
What is Go?
Go (a.k.a., Golang) is a programming language first developed at Google. It is a statically-typed language with syntax loosely derived from C, but with additional features such as garbage collection, type safety, some dynamic-typing capabilities, additional built-in types (e.g., variable-length arrays and key-value maps), and a large standard library.
How to use this image
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 amd64/golang:1.8 WORKDIR /go/src/app COPY . . RUN go-wrapper download # "go get -d -v ./..." RUN go-wrapper install # "go install -v ./..." CMD ["go-wrapper", "run"] # ["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
go-wrapper run includes
set -x so the binary name is printed to stderr on application startup. If this behavior is undesirable, then switching to
CMD ["app"] (or
CMD ["myapp"] if a Go custom import path is in use) will silence it by running the built binary directly.
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":/usr/src/myapp -w /usr/src/myapp amd64/golang:1.8 go build -v
This will add your current directory as a volume to the container, set the working directory to the volume, and run the command
go build which will tell go to compile the project in the working directory and output the executable to
myapp. Alternatively, if you have a
Makefile, you can run the
make command inside your container.
$ docker run --rm -v "$PWD":/usr/src/myapp -w /usr/src/myapp amd64/golang:1.8 make
Cross-compile your app inside the Docker container
If you need to compile your application for a platform other than
linux/amd64 (such as
$ docker run --rm -v "$PWD":/usr/src/myapp -w /usr/src/myapp -e GOOS=windows -e GOARCH=386 amd64/golang:1.8 go build -v
Alternatively, you can build for multiple platforms at once:
$ docker run --rm -it -v "$PWD":/usr/src/myapp -w /usr/src/myapp amd64/golang:1.8 bash $ for GOOS in darwin linux; do > for GOARCH in 386 amd64; do > go build -v -o myapp-$GOOS-$GOARCH > done > done
amd64/golang images come in many flavors, each designed for a specific use case.
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.
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 recommended when final image size being as small as possible is desired. The main caveat to note is that it does use musl libc instead of glibc and friends, so certain software might run into issues depending on the depth of their libc requirements. However, most software doesn't have an issue with this, so this variant is usually a very safe choice. 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, it's uncommon for additional related tools (such as
bash) to be 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).
ONBUILD image variants are deprecated, and their usage is discouraged. For more details, see docker-library/official-images#2076.
onbuild variant is really useful for "getting off the ground running" (zero to Dockerized in a short period of time), it's not recommended for long-term usage within a project due to the lack of control over when the
ONBUILD triggers fire (see also
Once you've got a handle on how your project functions within Docker, you'll probably want to adjust your
Dockerfile to inherit from a non-
onbuild variant and copy the commands from the
Dockerfile (moving the
ONBUILD lines to the end and removing the
ONBUILD keywords) into your own file so that you have tighter control over them and more transparency for yourself and others looking at your
Dockerfile as to what it does. This also makes it easier to add additional requirements as time goes on (such as installing more packages before performing the previously-
View license information for the software contained in this image.