Godep

Command godep helps build packages reproducibly by fixing their dependencies.

This tool assumes you are working in a standard Go workspace, as described in http://golang.org/doc/code.html.

Install

$ go get github.com/kr/godep

Getting Started

How to add godep in a new project.

Assuming you've got everything working already, so you can build your project with go install and test it with go test, it's one command to start using:

$ godep save

This will save a list of dependencies to the file Godeps. Read over its contents and make sure it looks reasonable. Then commit the file to version control.

You can also include the source code of all dependencies with flag -copy. This makes subsequent invocations of godep go faster and more reliable. For example, network failure will not cause problems running the go tool.

Edit-test Cycle

1. Edit code
2. Run godep go test
3. (repeat)

Add or Update a Dependency

To add or update package foo/bar, do this:

1. Run godep restore
2. Run go get -u foo/bar
3. Edit your code, if necessary, to import foo/bar.
4. Run godep save

Before committing the change, you'll probably want to inspect the changes to Godeps, for example with git diff, and make sure it looks reasonable.

Multiple Packages

If your repository has more than one package, you're probably accustomed to running commands like go test ./..., go install ./..., and go fmt ./.... Similarly, you should run godep save ./... to capture the dependencies of all packages.

Using Other Tools

The godep path command helps integrate with commands other than the standard go tool. This works with any tool that reads GOPATH from its environment, for example the recently-released oracle command.

$ GOPATH=`godep path`:$GOPATH
$ oracle -mode=implements .

File Format

Godeps is a json file with the following structure:

type Godeps struct {
	ImportPath string
	GoVersion  string   // Abridged output of 'go version'.
	Packages   []string // Arguments to godep save, if any.
	Deps       []struct {
		ImportPath string
		Comment    string // Description of commit, if present.
		Rev        string // VCS-specific commit ID.
	}
}

Example Godeps:

{
	"ImportPath": "github.com/kr/hk",
	"GoVersion": "go1.1.2",
	"Deps": [
		{
			"ImportPath": "code.google.com/p/go-netrc/netrc",
			"Rev": "28676070ab99"
		},
		{
			"ImportPath": "github.com/kr/binarydist",
			"Rev": "3380ade90f8b0dfa3e363fd7d7e941fa857d0d13"
		}
	]
}