Go app template build environment

This is a skeleton project for a Go application, which captures the best build
techniques I have learned to date. It uses a Makefile to drive the build (the
universal API to software projects) and a Dockerfile to build a docker image.

This has only been tested on Linux, and depends on Docker to build.

Customizing it

To use this, simply copy these files and make the following changes:

Makefile:

• change BIN to your binary name
• rename cmd/myapp to cmd/$BIN
• change PKG to the Go import path of this repo
• change REGISTRY to the Docker registry you want to use
• maybe change SRC_DIRS if you use some other layout
• choose a strategy for VERSION values - git tags or manual

Dockerfile.in:

• change the MAINTAINER to you
• maybe change or remove the USER if you need

Building

Run make or make build to compile your app. This will use a Docker image
to build your app, with the current directory volume-mounted into place. This
will store incremental state for the fastest possible build. Run make all-build to build for all architectures.

Run make container to build the container image. It will calculate the image
tag based on the most recent git tag, and whether the repo is "dirty" since
that tag (see make version). Run make all-container to build containers
for all architectures.

Run make push to push the container image to REGISTRY. Run make all-push
to push the container images for all architectures.

Run make clean to clean up.