buschjost/go-buildpack

Go support for Heroku

Buildpack: Go

This is a buildpack for Go.

Getting Started

Follow the guide at http://doc.scalingo.eu/languages/go.

There's also a hello world sample app at https://github.com/Scalingo/sample-go-martini.

Example

$ ls -A1
.git
Godeps
Procfile
web.go

$ scalingo create my-go-app
$ git push scalingo master
...
-----> Fetching custom git buildpack... done
-----> Go app detected
-----> Installing go1.4.2... done
-----> Running: godep go install -tags paas ./...
-----> Discovering process types
       Procfile declares types -> web

-----> Compressing... done, 1.6MB
-----> Launching... done, v4
       https://polar-waters-4785.herokuapp.com/ deployed to Heroku

This buildpack will detect your repository as Go if it contains a .go file.

The buildpack adds a paas build constraint, to enable Platform as a Service specific code. See the App Engine build constraints article for more.

.godir and Godeps

Early versions of this buildpack required users to create a .godir file in the root of the project, containing the application name in order to build the project. While using a .godir file is still supported, it has been deprecated in favor of using godep in your project to manage dependencies, and including the generated Godep directory in your git repository.

Using with cgo

This buildpack supports building with C dependencies via cgo. You can set config vars to specify CGO flags to, e.g., specify paths for vendored dependencies. E.g., to build gopgsqldriver, add the config var CGO_CFLAGS with the value -I/app/code/vendor/include/postgresql and include the relevant Postgres header files in vendor/include/postgresql/ in your app.

Setting the version at build time

If you set the GO_GIT_DESCRIBE_SYMBOL to the name of a string variable, it will be set at build time to the output of git describe --tags --always. This lets you access the commit id or tag in your app. For example, in your main.go:

package main

var version string

To set this variable at build time, set the config var:

$ scalingo env-set GO_GIT_DESCRIBE_SYMBOL=main.version