Cloud Foundry buildpack for Stack based Haskell projects. Based on the excellent heroku-buildpack-stack.

Push an app with version 1.0 of this buildpack:

$ cf push haskell-api -b  https://github.com/mikegehard/cloudfoundry-buildpack-haskell-stack#1.0 -m 2GB

If you're behind a proxy, simply set https_proxy environment variable to the desired value (e.g. in the manifest) and the buildpack will pick it up.

If your PCF instance is behind a proxy and you find yourself in a situation where:

• it takes one proxy setting to let your buildpack download Stack from the Internet (proxy.example.com:80)
• but it also takes another proxy setting to let Stack download its dependencies (http://user:[email protected])
• and those two proxy settings are different

this buildpack lets you configure your second proxy by setting the

stack_proxy

environment variable (e.g. in the manifest) to the desired value. The way the buildpack is going to work is:

• it will use the https_proxy as it would in the one proxy scenario
• as it detects the moment where Stack starts pulling its dependencies, it will temporarily swap the current proxy setting with with the stack_proxy setting.

---
applications:
- name: your-application-name
  buildpacks:
  - https://github.com/mikegehard/cloudfoundry-buildpack-haskell-stack
  instances: 1
  memory: 2G
  disk_quota: 2G
  health-check-type: process
  timeout: 180
  env:
    https_proxy: "proxy.example.com:80"
    stack_proxy: "http://user:[email protected]"

Note: The first push of an application requires a lot of memory to prime the Stack cache with all of the libraries. It is recommended that you set the app memory to 2GB for the first push and scale it back down after the push completes. You may also need to scale up before subsequent pushes and scale down after those pushes complete. It seems that the v3 Cloud Controller API will allow for setting the compilation container memory differently than the runtime container memory so this may go away in the future.

The application must pull the port to use from the PORT environment variable.

An example Scotty app:

main :: IO ()
main = do
    putStrLn "Starting server..."
    port <- lookupEnv "PORT"
    scotty (maybe 3000 read port) $ do
        WebApp.routes

See here for source code of an example app deployed to PWS.