Options for configuring a client.

A lens onto configuration of the connection manager provided by the http-client package.

In this example, we enable the use of OpenSSL for (hopefully) secure connections:

import OpenSSL.Session (context)
import Network.HTTP.Client.OpenSSL

let opts = defaults & manager .~ Left (opensslManagerSettings context)
withOpenSSL $
  getWith opts "https://httpbin.org/get"
 

In this example, we also set the response timeout to 10000 microseconds:

import OpenSSL.Session (context)
import Network.HTTP.Client.OpenSSL
import Network.HTTP.Client (defaultManagerSettings, managerResponseTimeout)

let opts = defaults & manager .~ Left (opensslManagerSettings context)
                    & manager .~ Left (defaultManagerSettings { managerResponseTimeout = Just 10000 } )

withOpenSSL $
  getWith opts "https://httpbin.org/get"
 

A lens onto proxy configuration.

Example:

let opts = defaults & proxy ?~ httpProxy "localhost" 8000
getWith opts "http://httpbin.org/get"
 

Note here the use of the ?~ setter to turn a Proxy into a Maybe Proxy, to make the type of the RHS compatible with the proxy lens.

A lens onto request authentication.

Example (note the use of TLS):

let opts = defaults & auth ?~ basicAuth "user" "pass"
getWith opts "https://httpbin.org/basic-auth/user/pass"
 

A lens onto all headers with the given name (there can legitimately be zero or more).

Example:

let opts = defaults & header "Accept" .~ ["*/*"]
getWith opts "http://httpbin.org/get"
 

A lens onto all query parameters with the given name (there can legitimately be zero or more).

In this example, we construct the query URL "http://httpbin.org/get?foo=bar&foo=quux".

let opts = defaults & param "foo" .~ ["bar", "quux"]
getWith opts "http://httpbin.org/get"
 

A lens onto the maximum number of redirects that will be followed before an exception is thrown.

In this example, a HttpException will be thrown with a TooManyRedirects constructor, because the maximum number of redirects allowed will be exceeded.

let opts = defaults & redirects .~ 3
getWith opts "http://httpbin.org/redirect/5"
 

A lens onto all headers (there can legitimately be zero or more).

In this example, we print all the headers sent by default with every request.

print (defaults ^. headers)
 

A lens onto all query parameters.

A traversal onto the cookie with the given name, if one exists.

N.B. This is an "illegal" Traversal': we can change the cookieName of the associated Cookie so that it differs from the name provided to this function.

A lens onto all cookies.

A lens to get the optional status check function

Define a HTTP proxy, consisting of a hostname and port number.

A lens onto the hostname portion of a proxy configuration.

A lens onto the TCP port number of a proxy configuration.

A lens onto the name of a cookie.

A lens onto the value of a cookie.

A lens onto the expiry time of a cookie.

A lens onto the domain of a cookie.

A lens onto the path of a cookie.

A lens onto the creation time of a cookie.

A lens onto the last access time of a cookie.

A lens onto whether a cookie is persistent across sessions (also known as a "tracking cookie").

A lens onto whether a cookie is host-only.

A lens onto whether a cookie is secure-only, such that it will only be used over TLS.

A lens onto whether a cookie is "HTTP-only".

Such cookies should be used only by browsers when transmitting HTTP requests. They must be unavailable in non-browser environments, such as when executing JavaScript scripts.

A simple representation of the HTTP response.

Since 0.1.0

A lens onto the body of a response.

r <- get "http://httpbin.org/get"
print (r ^. responseBody)
 

A lens onto all matching named headers in an HTTP response.

To access exactly one header (the result will be the empty string if there is no match), use the (^.) operator.

r <- get "http://httpbin.org/get"
print (r ^. responseHeader "Content-Type")
 

To access at most one header (the result will be Nothing if there is no match), use the (^?) operator.

r <- get "http://httpbin.org/get"
print (r ^? responseHeader "Content-Transfer-Encoding")
 

To access all (zero or more) matching headers, use the (^..) operator.

r <- get "http://httpbin.org/get"
print (r ^.. responseHeader "Set-Cookie")
 

A fold over Link headers, matching on both parameter name and value.

For example, here is a Link header returned by the GitHub search API.

Link:
  <https://api.github.com/search/code?q=addClass+user%3Amozilla&page=2>; rel="next",
  <https://api.github.com/search/code?q=addClass+user%3Amozilla&page=34>; rel="last"

And here is an example of how we can retrieve the URL for the next link programatically.

r <- get "https://api.github.com/search/code?q=addClass+user:mozilla"
print (r ^? responseLink "rel" "next" . linkURL)
 

A fold over any cookies that match the given name.

r <- get "http://www.nytimes.com/"
print (r ^? responseCookie "RMID")
 

A lens onto all headers in an HTTP response.

A lens onto all cookies set in the response.

A lens onto the status of an HTTP response.

A lens onto the version of an HTTP response.

HTTP Status.

Only the statusCode is used for comparisons.

Please use mkStatus to create status codes from code and message, or the Enum instance or the status code constants (like ok200). There might be additional record members in the future.

Note that the Show instance is only for debugging.

A lens onto the numeric identifier of an HTTP status.

A lens onto the textual description of an HTTP status.

An element of a Link header.

A lens onto the URL portion of a Link element.

A lens onto the parameters of a Link element.

A single part of a multipart message.

A lens onto the name of the input element associated with part of a multipart form upload.

A lens onto the filename associated with part of a multipart form upload.

A lens onto the content-type associated with part of a multipart form upload.

A lens onto the code that fetches the data associated with part of a multipart form upload.

Turn an attoparsec Parser into a Fold.

Both headers and bodies can contain complicated data that we may need to parse.

Example: when responding to an OPTIONS request, a server may return the list of verbs it supports in any order, up to and including changing the order on every request (which httpbin.org /actually does/!). To deal with this possibility, we parse the list, then sort it.

>>> import Data.Attoparsec.ByteString.Char8 as A
>>> import Data.List (sort)
>>> 
>>> let comma = skipSpace >> "," >> skipSpace
>>> let verbs = A.takeWhile isAlpha_ascii `sepBy` comma
>>> 
>>> r <- options "http://httpbin.org/get"
>>> r ^. responseHeader "Allow" . atto verbs . to sort
["GET","HEAD","OPTIONS"]

The same as atto, but ensures that the parser consumes the entire input.

Equivalent to:

atto_ myParser = atto (myParser <* endOfInput)