This method works with Go 1.11, 1.12, and should work with every 1.X future release.
- move your code outside of
go mod init [module path]: this will import dependencies from
go mod tidy: this will remove unnecessary imports, and add indirect ones.
rm -fr vendor/
go build: is everthing ok?
rm -f Gopkg.lock Gopkg.toml
git commit -m 'chore(dep): migrated from dep to Go 1.11 modules'
Before Go 1.11, dependency management was left to the community. There was many solutions, but my favorite was dep.
Like many dependency management tools from other languages, dep has a file for dependencies requests (
Gopkg.toml), a file to lock the exact versions used (
Gopkg.lock), and a
vendor directory to hold the dependency files. A simple command
dep ensure is doing all the work.
Also, before Go 1.11, you project source needed to be inside your
GOPATH and you had to respect a workspace layout.
Fortunately, with Go 1.11, your code can live anywhere on your disk! Also, dependency management is handled by the
go command, with the introduction of modules.
After installing Go 1.11, start by moving your code outside of
~/code $ mv go/src/gitlab.callr.tech/platform/asterisk-pbx-agi .
Now, my project is at
go mod init:
~/code/asterisk-pbx-agi $ go mod init go: cannot determine module path for source directory ~/code/asterisk-pbx-agi (outside GOPATH, no import comments)
Ah. So because the code is outside
GOPATH, go cannot determine the “module path” anymore. Makes sense.
Let’s try again with a module path:
~/code/asterisk-pbx-agi $ go mod init gitlab.callr.tech/platform/asterisk-pbx-agi go: creating new go.mod: module gitlab.callr.tech/platform/asterisk-pbx-agi go: copying requirements from Gopkg.lock
Go has imported my dependencies from dep by reading the
Gopkg.lock file. Neat. It also created a
module gitlab.callr.tech/platform/asterisk-pbx-agi require ( github.com/zaf/agi v0.0.0-20160319110841-15f1ed9d87e3 go.uber.org/atomic v1.3.2 go.uber.org/multierr v1.1.0 go.uber.org/zap v1.8.0 gopkg.in/yaml.v2 v2.2.1 )
At this point, a
go build should work.
But let’s try a
go mod tidy first. Here is
go.mod after running it:
module gitlab.callr.tech/platform/asterisk-pbx-agi require ( github.com/davecgh/go-spew v1.1.1 // indirect github.com/pkg/errors v0.8.0 // indirect github.com/pmezard/go-difflib v1.0.0 // indirect github.com/stretchr/testify v1.2.2 // indirect github.com/zaf/agi v0.0.0-20160319110841-15f1ed9d87e3 go.uber.org/atomic v1.3.2 // indirect go.uber.org/multierr v1.1.0 // indirect go.uber.org/zap v1.8.0 gopkg.in/yaml.v2 v2.2.1 )
go mod tidy has detected that some dependencies were “indirect” and marked them as such. It also added some other ones, needed for
go build and
go test work, you can safely remove the old files:
~/code/asterisk-pbx-agi $ rm -fr Gopkg.* vendor/
And you’re done.
Updating your CI
Using Gitlab, here is how we used to build with Go 1.10 and dep:
Build Go: image: golang:1.10 stage: build script: - curl -fsSL -o /usr/local/bin/dep https://github.com/golang/dep/releases/download/v0.4.1/dep-linux-amd64 && chmod +x /usr/local/bin/dep - ln -s `pwd` /go/src/asterisk-pbx-agi - cd /go/src/asterisk-pbx-agi - dep ensure -vendor-only - GOOS=linux GOARCH=amd64 go build -ldflags "-linkmode external -extldflags -static" -a -o callr.agi artifacts: paths: - callr.agi expire_in: 1 week
Because of the
GOPATH mess, we had to create a link to the code inside
/go/src, and run
go build inside it.
Here is the same task with Go 1.11:
Build Go: image: golang:1.11 stage: build script: - GOOS=linux GOARCH=amd64 go build -ldflags "-linkmode external -extldflags -static" -a -o callr.agi artifacts: paths: - callr.agi expire_in: 1 week
go build will handle the dependencies automatically.
2019-03-28 Update: this blog post has been updated to specify that the upgrade process works with Go 1.11 and beyond (1.12 tested and confirmed). It should work with all future 1.X releases.