language-dockerfile

Dockerfile linter, parser, pretty-printer and embedded DSL

https://github.com/beijaflor-io/language-dockerfile#readme

Version on this page:0.3.5.0
LTS Haskell 9.21:0.3.6.0
Stackage Nightly 2017-12-08:0.3.6.0
Latest on Hackage:0.3.6.0

See all snapshots language-dockerfile appears in

GPL-3.0-only licensed by Lukas Martinelli, Pedro Tacla Yamada
Maintained by [email protected]
This version can be pinned in stack with:language-dockerfile-0.3.5.0@sha256:77132c037b844c9d8ec25f83e50663218a6728eeb02966e03d62c7d966fc6f22,5514

haskell-language-dockerfile

Build Status CircleCI

Hackage

GH Pages Haddock

Blog Post in Portuguese


Dockerfile linter, parser, pretty-printer and embedded DSL, forked from hadolint.

Published on Hackage as language-dockerfile.

It extends hadolint with the pretty-printer and EDSL for writting Dockerfiles in Haskell.

Parsing files

import Language.Dockerfile
main = do
    ef <- parseFile "./Dockerfile"
    print ef

Parsing strings

import Language.Dockerfile
main = do
    c <- readFile "./Dockerfile"
    print (parseString c)

Pretty-printing files

import Language.Dockerfile
main = do
    Right d <- parseFile "./Dockerfile"
    putStr (prettyPrint d)

Writing Dockerfiles in Haskell

{-# LANGUAGE OverloadedStrings #-}
import Language.Dockerfile
main = putStr $ toDockerfileStr $ do
    from "node"
    run "apt-get update"
    runArgs ["apt-get", "install", "something"]
    -- ...

Using the QuasiQuoter

{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE QuasiQuotes       #-}
import Language.Dockerfile
main = putStr $ toDockerfileStr $ do
    from "node"
    run "apt-get update"
    [edockerfile|
    RUN apt-get update
    CMD node something.js
    |]
    -- ...

Templating Dockerfiles in Haskell

{-# LANGUAGE FlexibleContexts  #-}
{-# LANGUAGE OverloadedStrings #-}
import Control.Monad
import Language.Dockerfile
tags = ["7.8", "7.10", "8"]
cabalSandboxBuild packageName = do
    let cabalFile = packageName ++ ".cabal"
    run "cabal sandbox init"
    run "cabal update"
    add cabalFile ("/app/" ++ cabalFile)
    run "cabal install --only-dep -j"
    add "." "/app/"
    run "cabal build"
main =
    forM_ tags $ \tag -> do
        let df = toDockerfileStr $ do
            from ("haskell" `tagged` tag)
            cabalSandboxBuild "mypackage"
        writeFile ("./examples/templating-" ++ tag ++ ".dockerfile") df

Using IO in the DSL

By default the DSL runs in the Identity monad. By running in IO we can support more features like file globbing:

{-# LANGUAGE OverloadedStrings #-}
import           Language.Dockerfile
import qualified System.Directory     as Directory
import qualified System.FilePath      as FilePath
import qualified System.FilePath.Glob as Glob
main = do
    str <- toDockerfileStrIO $ do
        fs <- liftIO $ do
            cwd <- Directory.getCurrentDirectory
            fs <- Glob.glob "./test/*.hs"
            return (map (FilePath.makeRelative cwd) fs)
        from "ubuntu"
        mapM_ (\f -> add f ("/app/" ++ FilePath.takeFileName f)) fs
    putStr str

License

GPLv3