aesiniath / http-streams

Haskell HTTP client library for use with io-streams
https://hackage.haskell.org/package/http-streams
BSD 3-Clause "New" or "Revised" License
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An HTTP client

An HTTP client library for Haskell using the Snap Framework's io-streams library to handle the streaming IO.

A common case in writing RESTful web services is needing to make onward calls to further servers. This package is intended to make this easy to do. Though originally written for making calls from web apps written with Snap, you can use this from any library or framework.

Enjoy!

Example

The underlying API is very simple:

main :: IO ()
main = do
    c <- openConnection "www.example.com" 80

    let q = buildRequest1 $ do
                http GET "/"
                setAccept "text/html"

    sendRequest c q emptyBody

    receiveResponse c (\p i -> do
        putStr $ show p

        x <- Streams.read i
        S.putStr $ fromMaybe "" x)

    closeConnection c

There are also convenience functions for the common case of making straight-forward GET and POST requests; for instance:

    get "http://www.example.com/" (\_ i -> Streams.connect i stdout)

will {ahem} stream the response body to stdout. Perhaps more interesting (though less streams-oriented), is simply getting the response as a ByteString using one of the pre-defined handlers:

    x' <- get "https://secure.example.com/" concatHandler

See the documentation in Network.Http.Client for further examples and details of usage of the API.