--
-- HTTP client for use with io-streams
--
-- Copyright © 2012-2021 Athae Eredh Siniath and Others
--
-- The code in this file, and the program it is a part of, is
-- made available to you by its authors as open source software:
-- you can redistribute it and/or modify it under the terms of
-- the BSD licence.
--
{-# LANGUAGE CPP #-}
{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE DoAndIfThenElse #-}
{-# LANGUAGE OverloadedStrings #-}
{-# OPTIONS_HADDOCK hide, not-home #-}

module Network.Http.Connection (
    Connection (..),
    -- constructors only for testing
    makeConnection,
    withConnection,
    openConnection,
    openConnectionSSL,
    openConnectionUnix,
    closeConnection,
    getHostname,
    getRequestHeaders,
    getHeadersFull,
    sendRequest,
    receiveResponse,
    receiveResponseRaw,
    unsafeReceiveResponse,
    UnexpectedCompression,
    emptyBody,
    simpleBody,
    fileBody,
    inputStreamBody,
    debugHandler,
    simpleHandler,
    concatHandler,
) where

import Blaze.ByteString.Builder (Builder)
import qualified Blaze.ByteString.Builder as Builder (
    flush,
    fromByteString,
    toByteString,
 )
import qualified Blaze.ByteString.Builder.HTTP as Builder (chunkedTransferEncoding, chunkedTransferTerminator)
import Control.Exception (bracket)
import Data.ByteString (ByteString)
import qualified Data.ByteString.Char8 as S
import Network.Socket
import OpenSSL (withOpenSSL)
import OpenSSL.Session (SSL, SSLContext)
import qualified OpenSSL.Session as SSL
import System.IO.Streams (InputStream, OutputStream, stdout)
import qualified System.IO.Streams as Streams
import qualified System.IO.Streams.SSL as Streams hiding (connect)

#if !MIN_VERSION_base(4,8,0)
import Data.Monoid (mappend, mempty)
#endif

import Network.Http.Internal
import Network.Http.ResponseParser

{- |
A connection to a web server.
-}
data Connection = Connection
    { -- | will be used as the Host: header in the HTTP request.
      Connection -> ByteString
cHost :: ByteString
    , -- | called when the connection should be closed.
      Connection -> IO ()
cClose :: IO ()
    , Connection -> OutputStream Builder
cOut :: OutputStream Builder
    , Connection -> InputStream ByteString
cIn :: InputStream ByteString
    }

instance Show Connection where
    show :: Connection -> String
show Connection
c =
        {-# SCC "Connection.show" #-}
        forall (t :: * -> *) a. Foldable t => t [a] -> [a]
concat
            [ String
"Host: "
            , ByteString -> String
S.unpack forall a b. (a -> b) -> a -> b
$ Connection -> ByteString
cHost Connection
c
            , String
"\n"
            ]

{- |
Create a raw Connection object from the given parts. This is
primarily of use when teseting, for example:

> fakeConnection :: IO Connection
> fakeConnection = do
>     o  <- Streams.nullOutput
>     i  <- Streams.nullInput
>     c  <- makeConnection "www.example.com" (return()) o i
>     return c

is an idiom we use frequently in testing and benchmarking, usually
replacing the InputStream with something like:

>     x' <- S.readFile "properly-formatted-response.txt"
>     i  <- Streams.fromByteString x'

If you're going to do that, keep in mind that you /must/ have CR-LF
pairs after each header line and between the header and body to
be compliant with the HTTP protocol; otherwise, parsers will
reject your message.
-}
makeConnection ::
    -- | will be used as the @Host:@ header in the HTTP request.
    ByteString ->
    -- | an action to be called when the connection is terminated.
    IO () ->
    -- | write end of the HTTP client-server connection.
    OutputStream ByteString ->
    -- | read end of the HTTP client-server connection.
    InputStream ByteString ->
    IO Connection
makeConnection :: ByteString
-> IO ()
-> OutputStream ByteString
-> InputStream ByteString
-> IO Connection
makeConnection ByteString
h IO ()
c OutputStream ByteString
o1 InputStream ByteString
i = do
    OutputStream Builder
o2 <- OutputStream ByteString -> IO (OutputStream Builder)
Streams.builderStream OutputStream ByteString
o1
    forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$! ByteString
-> IO ()
-> OutputStream Builder
-> InputStream ByteString
-> Connection
Connection ByteString
h IO ()
c OutputStream Builder
o2 InputStream ByteString
i

{- |
Given an @IO@ action producing a 'Connection', and a computation
that needs one, runs the computation, cleaning up the
@Connection@ afterwards.

>     x <- withConnection (openConnection "s3.example.com" 80) $ (\c -> do
>         let q = buildRequest1 $ do
>             http GET "/bucket42/object/149"
>         sendRequest c q emptyBody
>         ...
>         return "blah")

which can make the code making an HTTP request a lot more
straight-forward.

Wraps @Control.Exception@'s 'Control.Exception.bracket'.
-}
withConnection :: IO Connection -> (Connection -> IO γ) -> IO γ
withConnection :: forall γ. IO Connection -> (Connection -> IO γ) -> IO γ
withConnection IO Connection
mkC =
    forall a b c. IO a -> (a -> IO b) -> (a -> IO c) -> IO c
bracket IO Connection
mkC Connection -> IO ()
closeConnection

{- |
In order to make a request you first establish the TCP
connection to the server over which to send it.

Ordinarily you would supply the host part of the URL here and it will
be used as the value of the HTTP 1.1 @Host:@ field. However, you can
specify any server name or IP addresss and set the @Host:@ value
later with 'Network.Http.Client.setHostname' when building the
request.

Usage is as follows:

>     c <- openConnection "localhost" 80
>     ...
>     closeConnection c

More likely, you'll use 'withConnection' to wrap the call in order
to ensure finalization.

HTTP pipelining is supported; you can reuse the connection to a
web server, but it's up to you to ensure you match the number of
requests sent to the number of responses read, and to process those
responses in order. This is all assuming that the /server/ supports
pipelining; be warned that not all do. Web browsers go to
extraordinary lengths to probe this; you probably only want to do
pipelining under controlled conditions. Otherwise just open a new
connection for subsequent requests.
-}
openConnection :: Hostname -> Port -> IO Connection
openConnection :: ByteString -> Port -> IO Connection
openConnection ByteString
h1' Port
p = do
    [AddrInfo]
is <- Maybe AddrInfo -> Maybe String -> Maybe String -> IO [AddrInfo]
getAddrInfo (forall a. a -> Maybe a
Just AddrInfo
hints) (forall a. a -> Maybe a
Just String
h1) (forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ forall a. Show a => a -> String
show Port
p)
    let addr :: AddrInfo
addr = forall a. [a] -> a
head [AddrInfo]
is
    let a :: SockAddr
a = AddrInfo -> SockAddr
addrAddress AddrInfo
addr
    Socket
s <- Family -> SocketType -> ProtocolNumber -> IO Socket
socket (AddrInfo -> Family
addrFamily AddrInfo
addr) SocketType
Stream ProtocolNumber
defaultProtocol

    Socket -> SockAddr -> IO ()
connect Socket
s SockAddr
a
    (InputStream ByteString
i, OutputStream ByteString
o1) <- Socket -> IO (InputStream ByteString, OutputStream ByteString)
Streams.socketToStreams Socket
s

    OutputStream Builder
o2 <- OutputStream ByteString -> IO (OutputStream Builder)
Streams.builderStream OutputStream ByteString
o1

    forall (m :: * -> *) a. Monad m => a -> m a
return
        Connection
            { cHost :: ByteString
cHost = ByteString
h2'
            , cClose :: IO ()
cClose = Socket -> IO ()
close Socket
s
            , cOut :: OutputStream Builder
cOut = OutputStream Builder
o2
            , cIn :: InputStream ByteString
cIn = InputStream ByteString
i
            }
  where
    hints :: AddrInfo
hints =
        AddrInfo
defaultHints
            { addrFlags :: [AddrInfoFlag]
addrFlags = [AddrInfoFlag
AI_NUMERICSERV]
            , addrSocketType :: SocketType
addrSocketType = SocketType
Stream
            }
    h2' :: ByteString
h2' =
        if Port
p forall a. Eq a => a -> a -> Bool
== Port
80
            then ByteString
h1'
            else [ByteString] -> ByteString
S.concat [ByteString
h1', ByteString
":", String -> ByteString
S.pack forall a b. (a -> b) -> a -> b
$ forall a. Show a => a -> String
show Port
p]
    h1 :: String
h1 = ByteString -> String
S.unpack ByteString
h1'

{- |
Open a secure connection to a web server.

> import OpenSSL (withOpenSSL)
>
> main :: IO ()
> main = do
>     ctx <- baselineContextSSL
>     c <- openConnectionSSL ctx "api.github.com" 443
>     ...
>     closeConnection c

If you want to tune the parameters used in making SSL connections,
manually specify certificates, etc, then setup your own context:

> import OpenSSL.Session (SSLContext)
> import qualified OpenSSL.Session as SSL
>
>     ...
>     ctx <- SSL.context
>     ...

See "OpenSSL.Session".

Crypto is as provided by the system @openssl@ library, as wrapped
by the @HsOpenSSL@ package and @openssl-streams@.

/There is no longer a need to call @withOpenSSL@ explicitly; the
initialization is invoked once per process for you/
-}
openConnectionSSL :: SSLContext -> Hostname -> Port -> IO Connection
openConnectionSSL :: SSLContext -> ByteString -> Port -> IO Connection
openConnectionSSL SSLContext
ctx ByteString
h1' Port
p = forall a. IO a -> IO a
withOpenSSL forall a b. (a -> b) -> a -> b
$ do
    [AddrInfo]
is <- Maybe AddrInfo -> Maybe String -> Maybe String -> IO [AddrInfo]
getAddrInfo forall a. Maybe a
Nothing (forall a. a -> Maybe a
Just String
h1) (forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ forall a. Show a => a -> String
show Port
p)

    let a :: SockAddr
a = AddrInfo -> SockAddr
addrAddress forall a b. (a -> b) -> a -> b
$ forall a. [a] -> a
head [AddrInfo]
is
        f :: Family
f = AddrInfo -> Family
addrFamily forall a b. (a -> b) -> a -> b
$ forall a. [a] -> a
head [AddrInfo]
is
    Socket
s <- Family -> SocketType -> ProtocolNumber -> IO Socket
socket Family
f SocketType
Stream ProtocolNumber
defaultProtocol

    Socket -> SockAddr -> IO ()
connect Socket
s SockAddr
a

    SSL
ssl <- SSLContext -> Socket -> IO SSL
SSL.connection SSLContext
ctx Socket
s
    SSL -> String -> IO ()
SSL.setTlsextHostName SSL
ssl String
h1
    SSL -> IO ()
SSL.connect SSL
ssl

    (InputStream ByteString
i, OutputStream ByteString
o1) <- SSL -> IO (InputStream ByteString, OutputStream ByteString)
Streams.sslToStreams SSL
ssl

    OutputStream Builder
o2 <- OutputStream ByteString -> IO (OutputStream Builder)
Streams.builderStream OutputStream ByteString
o1

    forall (m :: * -> *) a. Monad m => a -> m a
return
        Connection
            { cHost :: ByteString
cHost = ByteString
h2'
            , cClose :: IO ()
cClose = Socket -> SSL -> IO ()
closeSSL Socket
s SSL
ssl
            , cOut :: OutputStream Builder
cOut = OutputStream Builder
o2
            , cIn :: InputStream ByteString
cIn = InputStream ByteString
i
            }
  where
    h2' :: ByteString
    h2' :: ByteString
h2' =
        if Port
p forall a. Eq a => a -> a -> Bool
== Port
443
            then ByteString
h1'
            else [ByteString] -> ByteString
S.concat [ByteString
h1', ByteString
":", String -> ByteString
S.pack forall a b. (a -> b) -> a -> b
$ forall a. Show a => a -> String
show Port
p]
    h1 :: String
h1 = ByteString -> String
S.unpack ByteString
h1'

closeSSL :: Socket -> SSL -> IO ()
closeSSL :: Socket -> SSL -> IO ()
closeSSL Socket
s SSL
ssl = do
    SSL -> ShutdownType -> IO ()
SSL.shutdown SSL
ssl ShutdownType
SSL.Unidirectional
    Socket -> IO ()
close Socket
s

{- |
Open a connection to a Unix domain socket.

> main :: IO ()
> main = do
>     c <- openConnectionUnix "/var/run/docker.sock"
>     ...
>     closeConnection c
-}
openConnectionUnix :: FilePath -> IO Connection
openConnectionUnix :: String -> IO Connection
openConnectionUnix String
path = do
    let a :: SockAddr
a = String -> SockAddr
SockAddrUnix String
path
    Socket
s <- Family -> SocketType -> ProtocolNumber -> IO Socket
socket Family
AF_UNIX SocketType
Stream ProtocolNumber
defaultProtocol

    Socket -> SockAddr -> IO ()
connect Socket
s SockAddr
a
    (InputStream ByteString
i, OutputStream ByteString
o1) <- Socket -> IO (InputStream ByteString, OutputStream ByteString)
Streams.socketToStreams Socket
s

    OutputStream Builder
o2 <- OutputStream ByteString -> IO (OutputStream Builder)
Streams.builderStream OutputStream ByteString
o1

    forall (m :: * -> *) a. Monad m => a -> m a
return
        Connection
            { cHost :: ByteString
cHost = ByteString
path'
            , cClose :: IO ()
cClose = Socket -> IO ()
close Socket
s
            , cOut :: OutputStream Builder
cOut = OutputStream Builder
o2
            , cIn :: InputStream ByteString
cIn = InputStream ByteString
i
            }
  where
    path' :: ByteString
path' = String -> ByteString
S.pack String
path

{- |
Having composed a 'Request' object with the headers and metadata for
this connection, you can now send the request to the server, along
with the entity body, if there is one. For the rather common case of
HTTP requests like 'GET' that don't send data, use 'emptyBody' as the
output stream:

>     sendRequest c q emptyBody

For 'PUT' and 'POST' requests, you can use 'fileBody' or
'inputStreamBody' to send content to the server, or you can work with
the @io-streams@ API directly:

>     sendRequest c q (\o ->
>         Streams.write (Just (Builder.fromString "Hello World\n")) o)
-}

{-
    I would like to enforce the constraints on the Empty and Static
    cases shown here, but those functions take OutputStream ByteString,
    and we are of course working in OutputStream Builder by that point.
-}
sendRequest :: Connection -> Request -> (OutputStream Builder -> IO α) -> IO α
sendRequest :: forall α.
Connection -> Request -> (OutputStream Builder -> IO α) -> IO α
sendRequest Connection
c Request
q OutputStream Builder -> IO α
handler = do
    -- write the headers

    forall a. Maybe a -> OutputStream a -> IO ()
Streams.write (forall a. a -> Maybe a
Just Builder
msg) OutputStream Builder
o2

    -- deal with the expect-continue mess

    EntityBody
e2 <- case ExpectMode
t of
        ExpectMode
Normal -> do
            forall (m :: * -> *) a. Monad m => a -> m a
return EntityBody
e
        ExpectMode
Continue -> do
            forall a. Maybe a -> OutputStream a -> IO ()
Streams.write (forall a. a -> Maybe a
Just Builder
Builder.flush) OutputStream Builder
o2

            Response
p <- InputStream ByteString -> IO Response
readResponseHeader InputStream ByteString
i

            case Response -> Int
getStatusCode Response
p of
                Int
100 -> do
                    -- ok to send
                    forall (m :: * -> *) a. Monad m => a -> m a
return EntityBody
e
                Int
_ -> do
                    -- put the response back
                    forall a. a -> InputStream a -> IO ()
Streams.unRead (Response -> ByteString
rsp Response
p) InputStream ByteString
i
                    forall (m :: * -> *) a. Monad m => a -> m a
return EntityBody
Empty

    -- write the body, if there is one

    α
x <- case EntityBody
e2 of
        EntityBody
Empty -> do
            OutputStream Builder
o3 <- forall a. IO (OutputStream a)
Streams.nullOutput
            α
y <- OutputStream Builder -> IO α
handler OutputStream Builder
o3
            forall (m :: * -> *) a. Monad m => a -> m a
return α
y
        EntityBody
Chunking -> do
            OutputStream Builder
o3 <- forall a b. (a -> b) -> OutputStream b -> IO (OutputStream a)
Streams.contramap Builder -> Builder
Builder.chunkedTransferEncoding OutputStream Builder
o2
            α
y <- OutputStream Builder -> IO α
handler OutputStream Builder
o3
            forall a. Maybe a -> OutputStream a -> IO ()
Streams.write (forall a. a -> Maybe a
Just Builder
Builder.chunkedTransferTerminator) OutputStream Builder
o2
            forall (m :: * -> *) a. Monad m => a -> m a
return α
y
        (Static Int64
_) -> do
            -- o3 <- Streams.giveBytes (fromIntegral n :: Int64) o2
            α
y <- OutputStream Builder -> IO α
handler OutputStream Builder
o2
            forall (m :: * -> *) a. Monad m => a -> m a
return α
y

    -- push the stream out by flushing the output buffers

    forall a. Maybe a -> OutputStream a -> IO ()
Streams.write (forall a. a -> Maybe a
Just Builder
Builder.flush) OutputStream Builder
o2

    forall (m :: * -> *) a. Monad m => a -> m a
return α
x
  where
    o2 :: OutputStream Builder
o2 = Connection -> OutputStream Builder
cOut Connection
c
    e :: EntityBody
e = Request -> EntityBody
qBody Request
q
    t :: ExpectMode
t = Request -> ExpectMode
qExpect Request
q
    msg :: Builder
msg = Request -> ByteString -> Builder
composeRequestBytes Request
q ByteString
h'
    h' :: ByteString
h' = Connection -> ByteString
cHost Connection
c
    i :: InputStream ByteString
i = Connection -> InputStream ByteString
cIn Connection
c
    rsp :: Response -> ByteString
rsp Response
p = Builder -> ByteString
Builder.toByteString forall a b. (a -> b) -> a -> b
$ Response -> Builder
composeResponseBytes Response
p

{- |
Get the virtual hostname that will be used as the @Host:@ header in
the HTTP 1.1 request. Per RFC 2616 § 14.23, this will be of the form
@hostname:port@ if the port number is other than the default, ie 80
for HTTP.
-}
getHostname :: Connection -> Request -> ByteString
getHostname :: Connection -> Request -> ByteString
getHostname Connection
c Request
q =
    case Request -> Maybe ByteString
qHost Request
q of
        Just ByteString
h' -> ByteString
h'
        Maybe ByteString
Nothing -> Connection -> ByteString
cHost Connection
c

{-# DEPRECATED getRequestHeaders "use retrieveHeaders . getHeadersFull instead" #-}
getRequestHeaders :: Connection -> Request -> [(ByteString, ByteString)]
getRequestHeaders :: Connection -> Request -> [(ByteString, ByteString)]
getRequestHeaders Connection
c Request
q =
    (ByteString
"Host", Connection -> Request -> ByteString
getHostname Connection
c Request
q) forall a. a -> [a] -> [a]
: [(ByteString, ByteString)]
kvs
  where
    h :: Headers
h = Request -> Headers
qHeaders Request
q
    kvs :: [(ByteString, ByteString)]
kvs = Headers -> [(ByteString, ByteString)]
retrieveHeaders Headers
h

{- |
Get the headers that will be sent with this request. You likely won't
need this but there are some corner cases where people need to make
calculations based on all the headers before they go out over the wire.

If you'd like the request headers as an association list, import the header
functions:

> import Network.Http.Types

then use 'Network.Http.Types.retreiveHeaders' as follows:

>>> let kvs = retreiveHeaders $ getHeadersFull c q
>>> :t kvs
:: [(ByteString, ByteString)]
-}
getHeadersFull :: Connection -> Request -> Headers
getHeadersFull :: Connection -> Request -> Headers
getHeadersFull Connection
c Request
q =
    Headers
h'
  where
    h :: Headers
h = Request -> Headers
qHeaders Request
q
    h' :: Headers
h' = Headers -> ByteString -> ByteString -> Headers
updateHeader Headers
h ByteString
"Host" (Connection -> Request -> ByteString
getHostname Connection
c Request
q)

{- |
Handle the response coming back from the server. This function
hands control to a handler function you supply, passing you the
'Response' object with the response headers and an 'InputStream'
containing the entity body.

For example, if you just wanted to print the first chunk of the
content from the server:

>     receiveResponse c (\p i -> do
>         m <- Streams.read i
>         case m of
>             Just bytes -> putStr bytes
>             Nothing    -> return ())

Obviously, you can do more sophisticated things with the
'InputStream', which is the whole point of having an @io-streams@
based HTTP client library.

The final value from the handler function is the return value of
@receiveResponse@, if you need it.

Throws 'UnexpectedCompression' if it doesn't know how to handle the
compression format used in the response.
-}

{-
    The reponse body coming from the server MUST be fully read, even
    if (especially if) the users's handler doesn't consume it all.
    This is necessary to maintain the HTTP protocol invariants;
    otherwise pipelining would not work. It's not entirely clear
    *which* InputStream is being drained here; the underlying
    InputStream ByteString in Connection remains unconsumed beyond the
    threshold of the current response, which is exactly what we need.
-}
receiveResponse :: Connection -> (Response -> InputStream ByteString -> IO β) -> IO β
receiveResponse :: forall β.
Connection -> (Response -> InputStream ByteString -> IO β) -> IO β
receiveResponse Connection
c Response -> InputStream ByteString -> IO β
handler = do
    Response
p <- InputStream ByteString -> IO Response
readResponseHeader InputStream ByteString
i
    InputStream ByteString
i' <- Response -> InputStream ByteString -> IO (InputStream ByteString)
readResponseBody Response
p InputStream ByteString
i

    β
x <- Response -> InputStream ByteString -> IO β
handler Response
p InputStream ByteString
i'

    forall a. InputStream a -> IO ()
Streams.skipToEof InputStream ByteString
i'

    forall (m :: * -> *) a. Monad m => a -> m a
return β
x
  where
    i :: InputStream ByteString
i = Connection -> InputStream ByteString
cIn Connection
c

{- |
This is a specialized variant of 'receiveResponse' that /explicitly/ does
not handle the content encoding of the response body stream (it will not
decompress anything). Unless you really want the raw gzipped content coming
down from the server, use @receiveResponse@.
-}

{-
    See notes at receiveResponse.
-}
receiveResponseRaw :: Connection -> (Response -> InputStream ByteString -> IO β) -> IO β
receiveResponseRaw :: forall β.
Connection -> (Response -> InputStream ByteString -> IO β) -> IO β
receiveResponseRaw Connection
c Response -> InputStream ByteString -> IO β
handler = do
    Response
p <- InputStream ByteString -> IO Response
readResponseHeader InputStream ByteString
i
    let p' :: Response
p' =
            Response
p
                { pContentEncoding :: ContentEncoding
pContentEncoding = ContentEncoding
Identity
                }

    InputStream ByteString
i' <- Response -> InputStream ByteString -> IO (InputStream ByteString)
readResponseBody Response
p' InputStream ByteString
i

    β
x <- Response -> InputStream ByteString -> IO β
handler Response
p InputStream ByteString
i'

    forall a. InputStream a -> IO ()
Streams.skipToEof InputStream ByteString
i'

    forall (m :: * -> *) a. Monad m => a -> m a
return β
x
  where
    i :: InputStream ByteString
i = Connection -> InputStream ByteString
cIn Connection
c

{- |
Handle the response coming back from the server. This function
is the same as receiveResponse, but it does not consume the body for
you after the handler is done.  This means that it can only be safely used
if the handler will fully consume the body, there is no body, or when
the connection is not being reused (no pipelining).
-}
unsafeReceiveResponse :: Connection -> (Response -> InputStream ByteString -> IO β) -> IO β
unsafeReceiveResponse :: forall β.
Connection -> (Response -> InputStream ByteString -> IO β) -> IO β
unsafeReceiveResponse Connection
c Response -> InputStream ByteString -> IO β
handler = do
    Response
p <- InputStream ByteString -> IO Response
readResponseHeader InputStream ByteString
i
    InputStream ByteString
i' <- Response -> InputStream ByteString -> IO (InputStream ByteString)
readResponseBody Response
p InputStream ByteString
i

    Response -> InputStream ByteString -> IO β
handler Response
p InputStream ByteString
i'
  where
    i :: InputStream ByteString
i = Connection -> InputStream ByteString
cIn Connection
c

{- |
Use this for the common case of the HTTP methods that only send
headers and which have no entity body, i.e. 'GET' requests.
-}
emptyBody :: OutputStream Builder -> IO ()
emptyBody :: OutputStream Builder -> IO ()
emptyBody OutputStream Builder
_ = forall (m :: * -> *) a. Monad m => a -> m a
return ()

{- |
Sometimes you just want to send some bytes to the server as a the body of your
request. This is easy to use, but if you're doing anything massive use
'inputStreamBody'; if you're sending a file use 'fileBody'; if you have an
object that needs to be sent as JSON use 'jsonBody'
-}
simpleBody :: ByteString -> OutputStream Builder -> IO ()
simpleBody :: ByteString -> OutputStream Builder -> IO ()
simpleBody ByteString
x' OutputStream Builder
o = do
    let b :: Builder
b = ByteString -> Builder
Builder.fromByteString ByteString
x'
    forall a. Maybe a -> OutputStream a -> IO ()
Streams.write (forall a. a -> Maybe a
Just Builder
b) OutputStream Builder
o

{- |
Specify a local file to be sent to the server as the body of the
request.

You use this partially applied:

>     sendRequest c q (fileBody "/etc/passwd")

Note that the type of @(fileBody \"\/path\/to\/file\")@ is just what
you need for the third argument to 'sendRequest', namely

>>> :t filePath "hello.txt"
:: OutputStream Builder -> IO ()
-}

{-
    Relies on Streams.withFileAsInput generating (very) large chunks [which it
    does]. A more efficient way to do this would be interesting.
-}
fileBody :: FilePath -> OutputStream Builder -> IO ()
fileBody :: String -> OutputStream Builder -> IO ()
fileBody String
p OutputStream Builder
o = do
    forall a. String -> (InputStream ByteString -> IO a) -> IO a
Streams.withFileAsInput String
p (\InputStream ByteString
i -> InputStream ByteString -> OutputStream Builder -> IO ()
inputStreamBody InputStream ByteString
i OutputStream Builder
o)

{- |
Read from a pre-existing 'InputStream' and pipe that through to the
connection to the server. This is useful in the general case where
something else has handed you stream to read from and you want to use
it as the entity body for the request.

You use this partially applied:

>     i <- getStreamFromVault                    -- magic, clearly
>     sendRequest c q (inputStreamBody i)

This function maps "Builder.fromByteString" over the input, which will
be efficient if the ByteString chunks are large.
-}

{-
    Note that this has to be 'supply' and not 'connect' as we do not
    want the end of stream to prematurely terminate the chunked encoding
    pipeline!
-}
inputStreamBody :: InputStream ByteString -> OutputStream Builder -> IO ()
inputStreamBody :: InputStream ByteString -> OutputStream Builder -> IO ()
inputStreamBody InputStream ByteString
i1 OutputStream Builder
o = do
    InputStream Builder
i2 <- forall a b. (a -> b) -> InputStream a -> IO (InputStream b)
Streams.map ByteString -> Builder
Builder.fromByteString InputStream ByteString
i1
    forall a. InputStream a -> OutputStream a -> IO ()
Streams.supply InputStream Builder
i2 OutputStream Builder
o

{- |
Print the response headers and response body to @stdout@. You can
use this with 'receiveResponse' or one of the convenience functions
when testing. For example, doing:

>     c <- openConnection "kernel.operationaldynamics.com" 58080
>
>     let q = buildRequest1 $ do
>                 http GET "/time"
>
>     sendRequest c q emptyBody
>
>     receiveResponse c debugHandler

would print out:

> HTTP/1.1 200 OK
> Transfer-Encoding: chunked
> Content-Type: text/plain
> Vary: Accept-Encoding
> Server: Snap/0.9.2.4
> Content-Encoding: gzip
> Date: Mon, 21 Jan 2013 06:13:37 GMT
>
> Mon 21 Jan 13, 06:13:37.303Z

or thereabouts.
-}
debugHandler :: Response -> InputStream ByteString -> IO ()
debugHandler :: Response -> InputStream ByteString -> IO ()
debugHandler Response
p InputStream ByteString
i = do
    ByteString -> IO ()
S.putStr forall a b. (a -> b) -> a -> b
$ (Char -> Bool) -> ByteString -> ByteString
S.filter (forall a. Eq a => a -> a -> Bool
/= Char
'\r') forall a b. (a -> b) -> a -> b
$ Builder -> ByteString
Builder.toByteString forall a b. (a -> b) -> a -> b
$ Response -> Builder
composeResponseBytes Response
p
    forall a. InputStream a -> OutputStream a -> IO ()
Streams.connect InputStream ByteString
i OutputStream ByteString
stdout

{- |
Sometimes you just want the entire response body as a single blob.
This function concatonates all the bytes from the response into a
ByteString. If using the main @http-streams@ API, you would use it
as follows:

>    ...
>    x' <- receiveResponse c simpleHandler
>    ...

The methods in the convenience API all take a function to handle the
response; this function is passed directly to the 'receiveResponse'
call underlying the request. Thus this utility function can be used
for 'get' as well:

>    x' <- get "http://www.example.com/document.txt" simpleHandler

Either way, the usual caveats about allocating a
single object from streaming I/O apply: do not use this if you are
not absolutely certain that the response body will fit in a
reasonable amount of memory.

Note that this function makes no discrimination based on the
response's HTTP status code. You're almost certainly better off
writing your own handler function.
-}
simpleHandler :: Response -> InputStream ByteString -> IO ByteString
simpleHandler :: Response -> InputStream ByteString -> IO ByteString
simpleHandler Response
_ InputStream ByteString
i1 = do
    InputStream Builder
i2 <- forall a b. (a -> b) -> InputStream a -> IO (InputStream b)
Streams.map ByteString -> Builder
Builder.fromByteString InputStream ByteString
i1
    Builder
x <- forall s a. (s -> a -> s) -> s -> InputStream a -> IO s
Streams.fold forall a. Monoid a => a -> a -> a
mappend forall a. Monoid a => a
mempty InputStream Builder
i2
    forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$ Builder -> ByteString
Builder.toByteString Builder
x

concatHandler :: Response -> InputStream ByteString -> IO ByteString
concatHandler :: Response -> InputStream ByteString -> IO ByteString
concatHandler = Response -> InputStream ByteString -> IO ByteString
simpleHandler
{-# DEPRECATED concatHandler "Use simpleHandler instead" #-}

{- |
Shutdown the connection. You need to call this release the
underlying socket file descriptor and related network resources. To
do so reliably, use this in conjunction with 'openConnection' in a
call to 'Control.Exception.bracket':

> --
> -- Make connection, cleaning up afterward
> --
>
> foo :: IO ByteString
> foo = bracket
>    (openConnection "localhost" 80)
>    (closeConnection)
>    (doStuff)
>
> --
> -- Actually use Connection to send Request and receive Response
> --
>
> doStuff :: Connection -> IO ByteString

or, just use 'withConnection'.

While returning a ByteString is probably the most common use case,
you could conceivably do more processing of the response in 'doStuff'
and have it and 'foo' return a different type.
-}
closeConnection :: Connection -> IO ()
closeConnection :: Connection -> IO ()
closeConnection Connection
c = Connection -> IO ()
cClose Connection
c