Main.hs

{-# LANGUAGE OverloadedStrings #-}

import System.IO.Streams (InputStream, OutputStream, stdout)
import qualified System.IO.Streams as Streams
import qualified Data.ByteString as S

import Network.Http.Client

main :: IO ()
main = do
    c <- openConnectionUnix "/var/run/docker.sock"

    let q = buildRequest1 $ do
                http GET "/v1.12/containers/json"
                setAccept "application/json"

    sendRequest c q emptyBody

    receiveResponse c (\p i -> do
        let status = getStatusCode p

        case status of
            200 -> return ()
            otherwise -> error $ "Failed! Status code " ++ (show status)

        xm <- Streams.read i
        case xm of
            Just x    -> S.putStr x)
    closeConnection c

output.txt

[
    {
        "Command": "crate",
        "Created": 1440093436,
        "Id": "e1778874f60b5a4ff18a122606bfe2ba45ba41e2ba71b27ce8de1e2dd403aabd",
        "Image": "crate",
        "Labels": {},
        "Names": [
            "/crate"
        ],
        "Ports": [
            {
                "PrivatePort": 4300,
                "Type": "tcp"
            },
            {
                "IP": "0.0.0.0",
                "PrivatePort": 4200,
                "PublicPort": 4200,
                "Type": "tcp"
            }
        ],
        "Status": "Up About an hour"
    }
]