Godep
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. We expect godep to build on Go 1.4* or newer, but you can use it on any project that works with Go 1 or newer.
Install
$ go get github.com/tools/godep
How to use godep with 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/Godeps.json
and copy
their source code into vendor/
(or Godeps/_workspace/
when using older
versions of Go). Godep does not copy:
- files from source repositories that are not tracked in version control.
*_test.go
files.testdata
directories.- files outside of the go packages.
Godep does not process the imports of .go
files with either the ignore
or appengine
build tags.
Test files and testdata directories can be saved by adding -t
.
Read over the contents of vendor/
and make sure it looks reasonable. Then
commit the Godeps/
and vendor/
directories to version control.
-r
flag
The deprecated For older versions of Go, the -r
flag tells save to automatically rewrite
package import paths. This allows your code to refer directly to the copied
dependencies in Godeps/_workspace
. So, a package C that depends on package
D will actually import C/Godeps/_workspace/src/D
. This makes C's repo
self-contained and causes go get
to build C with the right version of all
dependencies.
If you don't use -r
, when using older version of Go, then in order to use the
fixed dependencies and get reproducible builds, you must make sure that every
time you run a Go-related command, you wrap it in one of these two ways:
- If the command you are running is just
go
, run it asgodep go ...
, e.g.godep go install -v ./...
- When using a different command, set your
$GOPATH
usinggodep path
as described below.
-r
isn't necessary with go1.6+ and isn't allowed.
Additional Operations
Restore
The godep restore
command is the opposite of godep save
. It will install the
package versions specified in Godeps/Godeps.json
to your $GOPATH
. This modifies the state of packages in your $GOPATH
.
Edit-test Cycle
- Edit code
- Run
godep go test
- (repeat)
Add a Dependency
To add a new package foo/bar, do this:
- Run
go get foo/bar
- Edit your code to import foo/bar.
- Run
godep save
(orgodep save ./...
).
Update a Dependency
To update a package from your $GOPATH
, do this:
- Run
go get -u foo/bar
- Run
godep update foo/bar
. (You can use the...
wildcard, for examplegodep update foo/...
).
Before comitting 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 in your application.
File Format
Godeps is a json file with the following structure:
type Godeps struct {
ImportPath string
GoVersion string // Abridged output of 'go version'.
GodepVersion string // Abridged output of 'godep 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": "go1.6",
"Deps": [
{
"ImportPath": "code.google.com/p/go-netrc/netrc",
"Rev": "28676070ab99"
},
{
"ImportPath": "github.com/kr/binarydist",
"Rev": "3380ade90f8b0dfa3e363fd7d7e941fa857d0d13"
}
]
}
Migrating to vendor/
Godep supports the Go 1.5+ vendor/
experiment
utilizing the same environment variable that the go tooling itself supports
(GO15VENDOREXPERIMENT
).
godep mostly works the same way as the go
command line tool. If you have go
1.5.X and set GO15VENDOREXPERIMENT=1
or have go1.6.X (or devel) vendor/
is enabled. Unless you already have a Godeps/_workspace
. This is a safety
feature and godep warns you about this.
When vendor/
is enabled godep will write the vendored code into the top level
./vendor/
directory. A ./Godeps/Godeps.json
file is created to track
the dependencies and revisions. vendor/
is not compatible with rewrites.
There is currently no automated migration between the old Godeps workspace and the vendor directory, but the following steps should work:
# just to be safe
$ unset GO15VENDOREXPERIMENT
# restore currently vendored deps to the $GOPATH
$ godep restore
# The next line is only needed to automatically undo rewritten imports that were
# created with godep save -r.
$ godep save -r=false <pkg spec>
# Remove the old Godeps folder
$ rm -rf Godeps
# If on go1.5.X to enable `vendor/`
$ export GO15VENDOREXPERIMENT=1
# re-analyze deps and save to `vendor/`.
$ godep save <pkg spec>
# Add the changes to your VCS
$ git add -A . ; git commit -am "Godep workspace -> vendor/"
# You should see your Godeps/_workspace/src files "moved" to vendor/.
Releasing
- Increment the version in
version.go
. - Tag the commit with the same version number.
- Update
Changelog.md
.