git-annex/P2P/Http/Client.hs
Joey Hess 509b23fa00
catch ClientError from withClientM
When getting from a P2P HTTP remote, prompt for credentials when required,
instead of failing.

This feels like it might be a bug in servant-client. withClientM's type
suggests it would not throw a ClientError. But it does in this case.
2024-08-07 11:24:34 -04:00

538 lines
15 KiB
Haskell

{- P2P protocol over HTTP, client
-
- https://git-annex.branchable.com/design/p2p_protocol_over_http/
-
- Copyright 2024 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE DataKinds, TypeApplications #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE CPP #-}
module P2P.Http.Client (
module P2P.Http.Client,
module P2P.Http.Types,
Validity(..),
) where
import Types
import P2P.Http.Types
import P2P.Protocol hiding (Offset, Bypass, auth, FileSize)
import Utility.Metered
import Utility.FileSize
import Types.NumCopies
import Annex.Common
#ifdef WITH_SERVANT
import qualified Annex
import Annex.UUID
import Annex.Url
import Types.Remote
import P2P.Http
import P2P.Http.Url
import Annex.Concurrent
import Utility.Url (BasicAuth(..))
import Utility.HumanTime
import qualified Git.Credential as Git
import Servant hiding (BasicAuthData(..))
import Servant.Client.Streaming
import qualified Servant.Types.SourceT as S
import Network.HTTP.Types.Status
import Network.HTTP.Client
import qualified Data.ByteString as B
import qualified Data.ByteString.Lazy.Internal as LI
import qualified Data.Map as M
import Control.Concurrent.STM
import Control.Concurrent.Async
import Control.Concurrent
import System.IO.Unsafe
#endif
import Data.Time.Clock.POSIX
import qualified Data.ByteString.Lazy as L
type ClientAction a
#ifdef WITH_SERVANT
= ClientEnv
-> ProtocolVersion
-> B64UUID ServerSide
-> B64UUID ClientSide
-> [B64UUID Bypass]
-> Maybe Auth
-> Annex (Either ClientError a)
#else
= ()
#endif
p2pHttpClient
:: Remote
-> (String -> Annex a)
-> ClientAction a
-> Annex a
p2pHttpClient rmt fallback clientaction =
p2pHttpClientVersions (const True) rmt fallback clientaction >>= \case
Just res -> return res
Nothing -> fallback "git-annex HTTP API server is missing an endpoint"
p2pHttpClientVersions
:: (ProtocolVersion -> Bool)
-> Remote
-> (String -> Annex a)
-> ClientAction a
-> Annex (Maybe a)
#ifdef WITH_SERVANT
p2pHttpClientVersions allowedversion rmt fallback clientaction =
case p2pHttpBaseUrl <$> remoteAnnexP2PHttpUrl (gitconfig rmt) of
Nothing -> error "internal"
Just baseurl -> do
mgr <- httpManager <$> getUrlOptions
let clientenv = mkClientEnv mgr baseurl
ccv <- Annex.getRead Annex.gitcredentialcache
Git.CredentialCache cc <- liftIO $ atomically $
readTMVar ccv
case M.lookup (Git.CredentialBaseURL credentialbaseurl) cc of
Nothing -> go clientenv Nothing False Nothing versions
Just cred -> go clientenv (Just cred) True (credauth cred) versions
where
versions = filter allowedversion allProtocolVersions
go clientenv mcred credcached mauth (v:vs) = do
myuuid <- getUUID
res <- catchclienterror $ clientaction clientenv v
(B64UUID (uuid rmt))
(B64UUID myuuid)
[]
mauth
case res of
Right resp -> do
unless credcached $ cachecred mcred
return (Just resp)
Left (FailureResponse _ resp)
| statusCode (responseStatusCode resp) == 404 && not (null vs) ->
go clientenv mcred credcached mauth vs
| statusCode (responseStatusCode resp) == 401 ->
case mcred of
Nothing -> authrequired clientenv (v:vs)
Just cred -> do
inRepo $ Git.rejectUrlCredential cred
Just <$> fallback (showstatuscode resp)
| otherwise -> Just <$> fallback (showstatuscode resp)
Left (ConnectionError ex) -> case fromException ex of
Just (HttpExceptionRequest _ (ConnectionFailure err)) -> Just <$> fallback
("unable to connect to HTTP server: " ++ show err)
_ -> Just <$> fallback (show ex)
Left clienterror -> Just <$> fallback
("git-annex HTTP API server returned an unexpected response: " ++ show clienterror)
go _ _ _ _ [] = return Nothing
catchclienterror a = a `catch` \(ex :: ClientError) -> pure (Left ex)
authrequired clientenv vs = do
cred <- prompt $
inRepo $ Git.getUrlCredential credentialbaseurl
go clientenv (Just cred) False (credauth cred) vs
showstatuscode resp =
show (statusCode (responseStatusCode resp))
++ " " ++
decodeBS (statusMessage (responseStatusCode resp))
credentialbaseurl = case p2pHttpUrlString <$> remoteAnnexP2PHttpUrl (gitconfig rmt) of
Nothing -> error "internal"
Just url -> url
credauth cred = do
ba <- Git.credentialBasicAuth cred
return $ Auth
(encodeBS (basicAuthUser ba))
(encodeBS (basicAuthPassword ba))
cachecred mcred = case mcred of
Just cred -> do
inRepo $ Git.approveUrlCredential cred
ccv <- Annex.getRead Annex.gitcredentialcache
liftIO $ atomically $ do
Git.CredentialCache cc <- takeTMVar ccv
putTMVar ccv $ Git.CredentialCache $
M.insert (Git.CredentialBaseURL credentialbaseurl) cred cc
Nothing -> noop
#else
p2pHttpClientVersions _ _ fallback () = Just <$> fallback
"This remote uses an annex+http url, but this version of git-annex is not built with support for that."
#endif
clientGet
:: Key
-> AssociatedFile
-> (L.ByteString -> IO BytesProcessed)
-- ^ Must consume the entire ByteString before returning its
-- total size.
-> Maybe FileSize
-- ^ Size of existing file, when resuming.
-> ClientAction Validity
#ifdef WITH_SERVANT
clientGet k af consumer startsz clientenv (ProtocolVersion ver) su cu bypass auth = liftIO $ do
let offset = fmap (Offset . fromIntegral) startsz
withClientM (cli (B64Key k) cu bypass baf offset auth) clientenv $ \case
Left err -> return (Left err)
Right respheaders -> do
b <- S.unSourceT (getResponse respheaders) gather
BytesProcessed len <- consumer b
let DataLength dl = case lookupResponseHeader @DataLengthHeader' respheaders of
Header hdr -> hdr
_ -> error "missing data length header"
return $ Right $
if dl == len then Valid else Invalid
where
cli =case ver of
3 -> v3 su V3
2 -> v2 su V2
1 -> v1 su V1
0 -> v0 su V0
_ -> error "unsupported protocol version"
v3 :<|> v2 :<|> v1 :<|> v0 :<|> _ = client p2pHttpAPI
gather = unsafeInterleaveIO . gather'
gather' S.Stop = return LI.Empty
gather' (S.Error err) = giveup err
gather' (S.Skip s) = gather' s
gather' (S.Effect ms) = ms >>= gather'
gather' (S.Yield v s) = LI.Chunk v <$> unsafeInterleaveIO (gather' s)
baf = associatedFileToB64FilePath af
#else
clientGet _ _ _ _ = ()
#endif
clientCheckPresent :: Key -> ClientAction Bool
#ifdef WITH_SERVANT
clientCheckPresent key clientenv (ProtocolVersion ver) su cu bypass auth =
liftIO $ withClientM (cli su (B64Key key) cu bypass auth) clientenv $ \case
Left err -> return (Left err)
Right (CheckPresentResult res) -> return (Right res)
where
cli = case ver of
3 -> flip v3 V3
2 -> flip v2 V2
1 -> flip v1 V1
0 -> flip v0 V0
_ -> error "unsupported protocol version"
_ :<|> _ :<|> _ :<|> _ :<|>
v3 :<|> v2 :<|> v1 :<|> v0 :<|> _ = client p2pHttpAPI
#else
clientCheckPresent _ = ()
#endif
-- Similar to P2P.Protocol.remove.
clientRemoveWithProof
:: Maybe SafeDropProof
-> Key
-> Annex RemoveResultPlus
-> Remote
-> Annex RemoveResultPlus
clientRemoveWithProof proof k unabletoremove remote =
case safeDropProofEndTime =<< proof of
Nothing -> removeanytime
Just endtime -> removebefore endtime
where
removeanytime = p2pHttpClient remote giveup (clientRemove k)
removebefore endtime =
p2pHttpClientVersions useversion remote giveup clientGetTimestamp >>= \case
Just (GetTimestampResult (Timestamp remotetime)) ->
removebefore' endtime remotetime
-- Peer is too old to support REMOVE-BEFORE.
Nothing -> removeanytime
removebefore' endtime remotetime =
canRemoveBefore endtime remotetime (liftIO getPOSIXTime) >>= \case
Just remoteendtime -> p2pHttpClient remote giveup $
clientRemoveBefore k (Timestamp remoteendtime)
Nothing -> unabletoremove
useversion v = v >= ProtocolVersion 3
clientRemove :: Key -> ClientAction RemoveResultPlus
#ifdef WITH_SERVANT
clientRemove k clientenv (ProtocolVersion ver) su cu bypass auth =
liftIO $ withClientM cli clientenv return
where
bk = B64Key k
cli = case ver of
3 -> v3 su V3 bk cu bypass auth
2 -> v2 su V2 bk cu bypass auth
1 -> plus <$> v1 su V1 bk cu bypass auth
0 -> plus <$> v0 su V0 bk cu bypass auth
_ -> error "unsupported protocol version"
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
v3 :<|> v2 :<|> v1 :<|> v0 :<|> _ = client p2pHttpAPI
#else
clientRemove _ = ()
#endif
clientRemoveBefore
:: Key
-> Timestamp
-> ClientAction RemoveResultPlus
#ifdef WITH_SERVANT
clientRemoveBefore k ts clientenv (ProtocolVersion ver) su cu bypass auth =
liftIO $ withClientM (cli su (B64Key k) cu bypass ts auth) clientenv return
where
cli = case ver of
3 -> flip v3 V3
_ -> error "unsupported protocol version"
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
v3 :<|> _ = client p2pHttpAPI
#else
clientRemoveBefore _ _ = ()
#endif
clientGetTimestamp :: ClientAction GetTimestampResult
#ifdef WITH_SERVANT
clientGetTimestamp clientenv (ProtocolVersion ver) su cu bypass auth =
liftIO $ withClientM (cli su cu bypass auth) clientenv return
where
cli = case ver of
3 -> flip v3 V3
_ -> error "unsupported protocol version"
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|>
v3 :<|> _ = client p2pHttpAPI
#else
clientGetTimestamp = ()
#endif
clientPut
:: MeterUpdate
-> Key
-> Maybe Offset
-> AssociatedFile
-> FilePath
-> FileSize
-> Annex Bool
-- ^ Called after sending the file to check if it's valid.
-> ClientAction PutResultPlus
#ifdef WITH_SERVANT
clientPut meterupdate k moffset af contentfile contentfilesize validitycheck clientenv (ProtocolVersion ver) su cu bypass auth = do
checkv <- liftIO newEmptyTMVarIO
checkresultv <- liftIO newEmptyTMVarIO
let checker = do
liftIO $ atomically $ takeTMVar checkv
validitycheck >>= liftIO . atomically . putTMVar checkresultv
checkerthread <- liftIO . async =<< forkState checker
v <- liftIO $ withBinaryFile contentfile ReadMode $ \h -> do
when (offset /= 0) $
hSeek h AbsoluteSeek offset
withClientM (cli (stream h checkv checkresultv)) clientenv return
case v of
Left err -> do
void $ liftIO $ atomically $ tryPutTMVar checkv ()
join $ liftIO (wait checkerthread)
return (Left err)
Right res -> do
join $ liftIO (wait checkerthread)
return (Right res)
where
stream h checkv checkresultv = S.SourceT $ \a -> do
bl <- hGetContentsMetered h meterupdate
v <- newMVar (0, filter (not . B.null) (L.toChunks bl))
a (go v)
where
go v = S.fromActionStep B.null $ modifyMVar v $ \case
(n, (b:[])) -> do
let !n' = n + B.length b
ifM (checkvalid n')
( return ((n', []), b)
-- The key's content is invalid, but
-- the amount of data is the same as
-- the DataLengthHeader indicates.
-- Truncate the stream by one byte to
-- indicate to the server that it's
-- not valid.
, return
( (n' - 1, [])
, B.take (B.length b - 1) b
)
)
(n, []) -> do
void $ checkvalid n
return ((n, []), mempty)
(n, (b:bs)) ->
let !n' = n + B.length b
in return ((n', bs), b)
checkvalid n = do
void $ liftIO $ atomically $ tryPutTMVar checkv ()
valid <- liftIO $ atomically $ readTMVar checkresultv
if not valid
then return (n /= fromIntegral nlen)
else return True
baf = case af of
AssociatedFile Nothing -> Nothing
AssociatedFile (Just f) -> Just (B64FilePath f)
len = DataLength nlen
nlen = contentfilesize - offset
offset = case moffset of
Nothing -> 0
Just (Offset o) -> fromIntegral o
bk = B64Key k
cli src = case ver of
3 -> v3 su V3 len bk cu bypass baf moffset src auth
2 -> v2 su V2 len bk cu bypass baf moffset src auth
1 -> plus <$> v1 su V1 len bk cu bypass baf moffset src auth
0 -> plus <$> v0 su V0 len bk cu bypass baf moffset src auth
_ -> error "unsupported protocol version"
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|>
_ :<|>
v3 :<|> v2 :<|> v1 :<|> v0 :<|> _ = client p2pHttpAPI
#else
clientPut _ _ _ _ _ _ _ = ()
#endif
clientPutOffset
:: Key
-> ClientAction PutOffsetResultPlus
#ifdef WITH_SERVANT
clientPutOffset k clientenv (ProtocolVersion ver) su cu bypass auth
| ver == 0 = return (Right (PutOffsetResultPlus (Offset 0)))
| otherwise = liftIO $ withClientM cli clientenv return
where
bk = B64Key k
cli = case ver of
3 -> v3 su V3 bk cu bypass auth
2 -> v2 su V2 bk cu bypass auth
1 -> plus <$> v1 su V1 bk cu bypass auth
_ -> error "unsupported protocol version"
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|>
_ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
v3 :<|> v2 :<|> v1 :<|> _ = client p2pHttpAPI
#else
clientPutOffset _ = ()
#endif
clientLockContent
:: Key
-> ClientAction LockResult
#ifdef WITH_SERVANT
clientLockContent k clientenv (ProtocolVersion ver) su cu bypass auth =
liftIO $ withClientM (cli (B64Key k) cu bypass auth) clientenv return
where
cli = case ver of
3 -> v3 su V3
2 -> v2 su V2
1 -> v1 su V1
0 -> v0 su V0
_ -> error "unsupported protocol version"
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|>
_ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|>
v3 :<|> v2 :<|> v1 :<|> v0 :<|> _ = client p2pHttpAPI
#else
clientLockContent _ = ()
#endif
clientKeepLocked
:: LockID
-> UUID
-> a
-> (VerifiedCopy -> Annex a)
-- ^ Callback is run only after successfully connecting to the http
-- server. The lock will remain held until the callback returns,
-- and then will be dropped.
-> ClientAction a
#ifdef WITH_SERVANT
clientKeepLocked lckid remoteuuid unablelock callback clientenv (ProtocolVersion ver) su cu bypass auth = do
readyv <- liftIO newEmptyTMVarIO
keeplocked <- liftIO newEmptyTMVarIO
let cli' = cli lckid (Just cu) bypass auth
(Just connectionKeepAlive) (Just keepAlive)
(S.fromStepT (unlocksender readyv keeplocked))
starttime <- liftIO getPOSIXTime
tid <- liftIO $ async $ withClientM cli' clientenv $ \case
Right (LockResult _ _) ->
atomically $ writeTMVar readyv (Right False)
Left err ->
atomically $ writeTMVar readyv (Left err)
let releaselock = liftIO $ do
atomically $ putTMVar keeplocked False
wait tid
liftIO (atomically $ takeTMVar readyv) >>= \case
Left err -> do
liftIO $ wait tid
return (Left err)
Right False -> do
liftIO $ wait tid
return (Right unablelock)
Right True -> do
let checker = return $ Left $ starttime + retentionduration
Right
<$> withVerifiedCopy LockedCopy remoteuuid checker callback
`finally` releaselock
where
retentionduration = fromIntegral $
durationSeconds p2pDefaultLockContentRetentionDuration
unlocksender readyv keeplocked =
S.Yield (UnlockRequest False) $ S.Effect $ do
return $ S.Effect $ do
liftIO $ atomically $ void $
tryPutTMVar readyv (Right True)
stilllocked <- liftIO $ atomically $
takeTMVar keeplocked
return $ if stilllocked
then unlocksender readyv keeplocked
else S.Yield (UnlockRequest True) S.Stop
cli = case ver of
3 -> v3 su V3
2 -> v2 su V2
1 -> v1 su V1
0 -> v0 su V0
_ -> error "unsupported protocol version"
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|>
_ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|>
_ :<|> _ :<|> _ :<|> _ :<|>
v3 :<|> v2 :<|> v1 :<|> v0 :<|> _ = client p2pHttpAPI
#else
clientKeepLocked _ _ _ _ = ()
#endif