fradrive/src/Handler/Admin/Test/Download.hs

110 lines
3.8 KiB
Haskell

-- SPDX-FileCopyrightText: 2022 Gregor Kleen <gregor.kleen@ifi.lmu.de>
--
-- SPDX-License-Identifier: AGPL-3.0-or-later
module Handler.Admin.Test.Download
( testDownload
, generateDownload', Random.seedNew
) where
import Import hiding (Builder)
import Handler.Utils
import qualified Crypto.Random as Random
import qualified Data.ByteString.Base64.URL as Base64
import qualified Data.Conduit.Combinators as C
import qualified Data.Binary as Binary
import Data.Binary.Builder (Builder)
import Control.Monad.Random.Lazy (evalRandT, liftRandT)
import qualified Database.Esqueleto.Legacy as E hiding (random_)
import qualified Database.Esqueleto.PostgreSQL as E
data TestDownloadMode
= TestDownloadDirect
| TestDownloadInTransaction
| TestDownloadFromDatabase
deriving (Eq, Ord, Enum, Bounded, Read, Show, Generic)
deriving anyclass (Universe, Finite, Binary)
nullaryPathPiece ''TestDownloadMode $ camelToPathPiece' 2
embedRenderMessage ''UniWorX ''TestDownloadMode id
data TestDownloadOptions = TestDownloadOptions
{ dlSeed :: Random.Seed
, dlMaxSize, dlChunkSize :: Int
, dlMode :: TestDownloadMode
} deriving (Generic)
deriving anyclass (Binary)
testDownloadForm :: Form TestDownloadOptions
testDownloadForm = identifyForm FIDTestDownload . renderWForm FormStandard $ do
randomSeed <- liftIO Random.seedNew
maxSizeRes <- wreq intField (fslI MsgTestDownloadMaxSize) . Just $ 2 * 2^30
modeRes <- wpopt (selectField optionsFinite) (fslI MsgTestDownloadMode) $ Just TestDownloadDirect
return $ TestDownloadOptions
randomSeed
<$> maxSizeRes
<*> pure (2^20)
<*> modeRes
generateDownload :: Monad m => TestDownloadOptions -> ConduitT i ByteString m ()
generateDownload TestDownloadOptions{..}
= C.unfold genChunk dlMaxSize .| generateDownload' dlSeed
where genChunk remaining
| remaining >= dlChunkSize = Just (dlChunkSize, remaining - dlChunkSize)
| remaining <= 0 = Nothing
| otherwise = Just (remaining, 0)
generateDownload' :: Monad m => Random.Seed -> ConduitT Int ByteString m ()
generateDownload' seed = transPipe (evalRandT ?? Random.drgNewSeed seed) $
C.mapM (liftRandT . (return .) . Random.randomBytesGenerate)
testDownload :: Handler Widget
testDownload = do
((dlRes, dlForm), dlEnctype) <- runFormPost testDownloadForm
formResult dlRes $ \opts@TestDownloadOptions{..} -> do
addHeader "Test-Download-Options" . decodeUtf8 . Base64.encode . toStrict $ Binary.encode opts
setContentDisposition ContentAttachment $ Just "u2w-test-download.bin"
let
sendDownload :: forall m. Monad m => ConduitT ByteString (Flush Builder) m ()
sendDownload = awaitForever $ \bs -> sendChunkBS bs >> sendFlush
sourceDBChunks :: ConduitT () Int DB ()
sourceDBChunks = forever sourceDBFiles
.| C.mapM (\x -> x <$ $logDebugS "testDownload.sourceDBChunks" (tshow $ entityKey x))
.| C.map ((length $!!) . fileContentChunkContent . entityVal)
.| takeLimit dlMaxSize
where
sourceDBFiles = E.selectSource . E.from $ \fileContentChunk -> do
E.orderBy [E.asc $ E.random_ @Int64]
return fileContentChunk
takeLimit n | n <= 0 = return ()
takeLimit n = do
c <- await
$logDebugS "testDownload.takeLimit" $ tshow c
case c of
Nothing -> return ()
Just c' -> yield c' >> takeLimit (n - c')
(sendResponse =<<) $ case dlMode of
TestDownloadDirect -> respondSource typeOctet $ generateDownload opts .| sendDownload
TestDownloadInTransaction -> respondSourceDB typeOctet $ generateDownload opts .| sendDownload
TestDownloadFromDatabase -> respondSourceDB typeOctet $ sourceDBChunks .| generateDownload' dlSeed .| sendDownload
return $
wrapForm dlForm def
{ formEncoding = dlEnctype
}