ghcup-hs/lib/GHCup/Download/IOStreams.hs
2021-03-24 17:56:57 +01:00

250 lines
8.3 KiB
Haskell

{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TypeFamilies #-}
module GHCup.Download.IOStreams where
import GHCup.Download.Utils
import GHCup.Errors
import GHCup.Types.Optics
import GHCup.Types.JSON ( )
import GHCup.Utils.File
import GHCup.Utils.Prelude
import Control.Applicative
import Control.Exception.Safe
import Control.Monad
import Control.Monad.Reader
import Data.ByteString ( ByteString )
import Data.ByteString.Builder
import Data.CaseInsensitive ( CI )
import Data.IORef
import Data.Maybe
import Data.Text.Read
import HPath
import HPath.IO as HIO
import Haskus.Utils.Variant.Excepts
import Network.Http.Client hiding ( URL )
import Optics
import Prelude hiding ( abs
, readFile
, writeFile
)
import "unix" System.Posix.IO.ByteString
hiding ( fdWrite )
import "unix-bytestring" System.Posix.IO.ByteString
( fdWrite )
import System.ProgressBar
import URI.ByteString
import qualified Data.ByteString as BS
import qualified Data.ByteString.Lazy as L
import qualified Data.Map.Strict as M
import qualified System.IO.Streams as Streams
----------------------------
--[ Low-level (non-curl) ]--
----------------------------
-- | Load the result of this download into memory at once.
downloadBS' :: MonadIO m
=> Bool -- ^ https?
-> ByteString -- ^ host (e.g. "www.example.com")
-> ByteString -- ^ path (e.g. "/my/file") including query
-> Maybe Int -- ^ optional port (e.g. 3000)
-> Excepts
'[ HTTPStatusError
, URIParseError
, UnsupportedScheme
, NoLocationHeader
, TooManyRedirs
]
m
L.ByteString
downloadBS' https host path port = do
bref <- liftIO $ newIORef (mempty :: Builder)
let stepper bs = modifyIORef bref (<> byteString bs)
downloadInternal False https host path port stepper
liftIO (readIORef bref <&> toLazyByteString)
downloadToFile :: (MonadMask m, MonadIO m)
=> Bool -- ^ https?
-> ByteString -- ^ host (e.g. "www.example.com")
-> ByteString -- ^ path (e.g. "/my/file") including query
-> Maybe Int -- ^ optional port (e.g. 3000)
-> Path Abs -- ^ destination file to create and write to
-> Excepts '[DownloadFailed] m ()
downloadToFile https host fullPath port destFile = do
fd <- liftIO $ createRegularFileFd newFilePerms destFile
let stepper = fdWrite fd
flip finally (liftIO $ closeFd fd)
$ reThrowAll DownloadFailed $ downloadInternal True https host fullPath port stepper
downloadInternal :: MonadIO m
=> Bool -- ^ whether to show a progress bar
-> Bool -- ^ https?
-> ByteString -- ^ host
-> ByteString -- ^ path with query
-> Maybe Int -- ^ optional port
-> (ByteString -> IO a) -- ^ the consuming step function
-> Excepts
'[ HTTPStatusError
, URIParseError
, UnsupportedScheme
, NoLocationHeader
, TooManyRedirs
]
m
()
downloadInternal = go (5 :: Int)
where
go redirs progressBar https host path port consumer = do
r <- liftIO $ withConnection' https host port action
veitherToExcepts r >>= \case
Just r' ->
if redirs > 0 then followRedirectURL r' else throwE TooManyRedirs
Nothing -> pure ()
where
action c = do
let q = buildRequest1 $ http GET path
sendRequest c q emptyBody
receiveResponse
c
(\r i' -> runE $ do
let scode = getStatusCode r
if
| scode >= 200 && scode < 300 -> downloadStream r i' >> pure Nothing
| scode >= 300 && scode < 400 -> case getHeader r "Location" of
Just r' -> pure $ Just r'
Nothing -> throwE NoLocationHeader
| otherwise -> throwE $ HTTPStatusError scode
)
followRedirectURL bs = case parseURI strictURIParserOptions bs of
Right uri' -> do
(https', host', fullPath', port') <- liftE $ uriToQuadruple uri'
go (redirs - 1) progressBar https' host' fullPath' port' consumer
Left e -> throwE e
downloadStream r i' = do
let size = case getHeader r "Content-Length" of
Just x' -> case decimal $ decUTF8Safe x' of
Left _ -> 0
Right (r', _) -> r'
Nothing -> 0
mpb <- if progressBar
then Just <$> liftIO (newProgressBar defStyle 10 (Progress 0 size ()))
else pure Nothing
outStream <- liftIO $ Streams.makeOutputStream
(\case
Just bs -> do
forM_ mpb $ \pb -> incProgress pb (BS.length bs)
void $ consumer bs
Nothing -> pure ()
)
liftIO $ Streams.connect i' outStream
getHead :: (MonadCatch m, MonadIO m)
=> URI
-> Excepts
'[ HTTPStatusError
, URIParseError
, UnsupportedScheme
, NoLocationHeader
, TooManyRedirs
, ProcessError
]
m
(M.Map (CI ByteString) ByteString)
getHead uri' | scheme == "https" = head' True
| scheme == "http" = head' False
| otherwise = throwE UnsupportedScheme
where
scheme = view (uriSchemeL' % schemeBSL') uri'
head' https = do
(_, host', fullPath', port') <- liftE $ uriToQuadruple uri'
liftE $ headInternal https host' fullPath' port'
headInternal :: MonadIO m
=> Bool -- ^ https?
-> ByteString -- ^ host
-> ByteString -- ^ path with query
-> Maybe Int -- ^ optional port
-> Excepts
'[ HTTPStatusError
, URIParseError
, UnsupportedScheme
, TooManyRedirs
, NoLocationHeader
]
m
(M.Map (CI ByteString) ByteString)
headInternal = go (5 :: Int)
where
go redirs https host path port = do
r <- liftIO $ withConnection' https host port action
veitherToExcepts r >>= \case
Left r' ->
if redirs > 0 then followRedirectURL r' else throwE TooManyRedirs
Right hs -> pure hs
where
action c = do
let q = buildRequest1 $ http HEAD path
sendRequest c q emptyBody
unsafeReceiveResponse
c
(\r _ -> runE $ do
let scode = getStatusCode r
if
| scode >= 200 && scode < 300 -> do
let headers = getHeaderMap r
pure $ Right headers
| scode >= 300 && scode < 400 -> case getHeader r "Location" of
Just r' -> pure $ Left r'
Nothing -> throwE NoLocationHeader
| otherwise -> throwE $ HTTPStatusError scode
)
followRedirectURL bs = case parseURI strictURIParserOptions bs of
Right uri' -> do
(https', host', fullPath', port') <- liftE $ uriToQuadruple uri'
go (redirs - 1) https' host' fullPath' port'
Left e -> throwE e
withConnection' :: Bool
-> ByteString
-> Maybe Int
-> (Connection -> IO a)
-> IO a
withConnection' https host port = bracket acquire closeConnection
where
acquire = case https of
True -> do
ctx <- baselineContextSSL
openConnectionSSL ctx host (fromIntegral $ fromMaybe 443 port)
False -> openConnection host (fromIntegral $ fromMaybe 80 port)