Go Vanity URLs is a simple Go server that allows you to set custom import paths for your Go packages. It also can run on Google App Engine.
Install and run the binary:
$ go get -u github.com/GoogleCloudPlatform/govanityurls
$ # update vanity.yaml
$ govanityurls
$ # open http://localhost:8080
Install gcloud and install Go App Engine component:
$ gcloud components install app-engine-go
Setup a custom domain for your app.
Get the application:
git clone https://github.com/GoogleCloudPlatform/govanityurls
cd govanityurls
Edit vanity.yaml to add any number of git repos. E.g., customdomain.com/portmidi will
serve the https://github.com/rakyll/portmidi repo.
paths:
  /portmidi:
    repo: https://github.com/rakyll/portmidi
You can add as many rules as you wish.
Deploy the app:
$ gcloud app deploy
That's it! You can use go get to get the package from your custom domain.
$ go get customdomain.com/portmidi
You can also deploy this as an App Engine Flexible app by changing the
app.yaml file:
runtime: go
env: flex
This project is a normal Go HTTP server, so you can also incorporate the handler into larger Go servers.
host: example.com
cache_max_age: 3600
paths:
  /foo:
    repo: https://github.com/example/foo
    display: "https://github.com/example/foo https://github.com/example/foo/tree/master{/dir} https://github.com/example/foo/blob/master{/dir}/{file}#L{line}"
    vcs: git
| Key | Required | Description | 
|---|---|---|
cache_max_age | 
      optional | The amount of time to cache package pages in seconds.  Controls the max-age directive sent in the Cache-Control HTTP header. | 
    
host | 
      optional | Host name to use in meta tags. If omitted, uses the App Engine default version host or the Host header on non-App Engine Standard environments. You can use this option to fix the host when using this service behind a reverse proxy or a custom dispatch file. | 
paths | 
      required | Map of paths to path configurations. Each key is a path that will point to the root of a repository hosted elsewhere. The fields are documented in the Path Configuration section below. | 
| Key | Required | Description | 
|---|---|---|
display | 
      optional | The last three fields of the go-source meta tag.  If omitted, it is inferred from the code hosting service if possible. | 
    
repo | 
      required | Root URL of the repository as it would appear in go-import meta tag. | 
    
vcs | 
      required if ambiguous | If the version control system cannot be inferred (e.g. for Bitbucket or a custom domain), then this specifies the version control system as it would appear in go-import meta tag.  This can be one of git, hg, svn, or bzr. |