-- -- HTTP client for use with io-streams -- -- Copyright © 2012-2014 Operational Dynamics Consulting, Pty Ltd -- -- 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 OverloadedStrings #-} {-# OPTIONS -fno-warn-orphans #-} -- | -- Maintainer: Andrew Cowie -- Stability: Experimental -- -- /Overview/ -- -- A simple HTTP client library, using the Snap Framework's @io-streams@ -- library to handle the streaming I\/O. The @http-streams@ API is designed -- for ease of use when querying web services and dealing with the result. -- -- Given: -- -- > {-# LANGUAGE OverloadedStrings #-} -- > -- > import System.IO.Streams (InputStream, OutputStream, stdout) -- > import qualified System.IO.Streams as Streams -- > import qualified Data.ByteString as S -- -- and this library: -- -- > import Network.Http.Client -- -- the underlying API is straight-forward. In particular, constructing the -- 'Request' to send is quick and to the point: -- -- @ -- 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 -- xm <- Streams.read i -- case xm of -- Just x -> S.putStr x -- Nothing -> \"\") -- -- \ 'closeConnection' c -- @ -- -- which would print the first chunk of the response back from the -- server. Obviously in real usage you'll do something more interesting -- with the 'Response' in the handler function, and consume the entire -- response body from the InputStream ByteString. -- -- Because this is all happening in 'IO' (the defining feature of -- @io-streams@!), you can ensure resource cleanup on normal or -- abnormal termination by using @Control.Exception@'s standard -- 'Control.Exception.bracket' function; see 'closeConnection' for an -- example. For the common case we have a utility function which -- wraps @bracket@ for you: -- -- @ -- foo :: IO ByteString -- foo = 'withConnection' ('openConnection' \"www.example.com\" 80) doStuff -- -- doStuff :: Connection -> IO ByteString -- @ -- -- There are also a set of convenience APIs that do just that, along with -- the tedious bits like parsing URLs. For example, to do an HTTP GET and -- stream the response body to stdout, you can simply do: -- -- @ -- 'get' \"http:\/\/www.example.com\/file.txt\" (\\p i -> Streams.connect i stdout) -- @ -- -- which on the one hand is \"easy\" while on the other exposes the the -- 'Response' and InputStream for you to read from. Of course, messing -- around with URLs is all a bit inefficient, so if you already have e.g. -- hostname and path, or if you need more control over the request being -- created, then the underlying @http-streams@ API is simple enough to use -- directly. -- module Network.Http.Client ( -- * Connecting to server Hostname, Port, Connection, openConnection, openConnectionUnix, -- * Building Requests -- | You setup a request using the RequestBuilder monad, and -- get the resultant Request object by running 'buildRequest1'. The -- first call doesn't have to be to 'http', but it looks better when -- it is, don't you think? Method(..), RequestBuilder, buildRequest1, buildRequest, http, setHostname, setAccept, setAccept', setAuthorizationBasic, ContentType, setContentType, setContentLength, setExpectContinue, setTransferEncoding, setHeader, -- * Sending HTTP request Request, Response, getHostname, sendRequest, emptyBody, fileBody, inputStreamBody, encodedFormBody, -- * Processing HTTP response receiveResponse, receiveResponseRaw, UnexpectedCompression, StatusCode, getStatusCode, getStatusMessage, getHeader, debugHandler, concatHandler, concatHandler', HttpClientError(..), jsonHandler, -- * Resource cleanup closeConnection, withConnection, -- * Convenience APIs -- | Some simple functions for making requests with useful defaults. -- There's no @head@ function for the usual reason of needing to -- avoid collision with @Prelude@. -- -- These convenience functions work with @http@ and @https@, but -- note that if you retrieve an @https@ URL, you /must/ wrap your -- @main@ function with 'OpenSSL.withOpenSSL' to initialize the -- native openssl library code. -- URL, get, TooManyRedirects, post, postForm, put, -- * Secure connections openConnectionSSL, baselineContextSSL, modifyContextSSL, establishConnection, -- * Testing support makeConnection, Headers, getHeaders, getHeadersFull, -- * Deprecated getRequestHeaders ) where import Network.Http.Types import Network.Http.Connection import Network.Http.Inconvenience