Network.Wai.Middleware.Routes.Routes

This package provides typesafe URLs for Wai applications.

Quasi Quoters

parseRoutes :: QuasiQuoter

A quasi-quoter to parse a string into a list of Resources. Checks for overlapping routes, failing if present; use parseRoutesNoCheck to skip the checking. See documentation site for details on syntax.

Parse Routes declared inline

parseRoutesFile :: FilePath -> Q Exp

Parse routes declared in a file

parseRoutesNoCheck :: QuasiQuoter

Same as parseRoutes, but performs no overlap checking.

Parse routes declared inline, without checking for overlaps

parseRoutesFileNoCheck :: FilePath -> Q Exp

Parse routes declared in a file, without checking for overlaps

Template Haskell methods

mkRoute :: String -> [ResourceTree String] -> Q [Dec]

Generates all the things needed for efficient routing, including your application's Route datatype, and RenderRoute, ParseRoute, and RouteAttr instances

Dispatch

routeDispatch :: Routable master => master -> Middleware

Generates the application middleware from a Routable master datatype

URL rendering and parsing

showRoute :: RenderRoute master => Route master -> Text

Renders a Route as Text

readRoute :: ParseRoute master => Text -> Maybe (Route master)

Read a route from Text Returns Nothing if Route reading failed. Just route otherwise

Application Handlers

type Handler master = master -> RequestData -> ResponseHandler

A Handler generates an App from the master datatype

As of Wai 3, Application datatype now follows continuation passing style

type ResponseHandler = (Response -> IO ResponseReceived) -> IO ResponseReceived

Generated Datatypes

class Routable master where

A Routable instance can be used in dispatching. An appropriate instance for your site datatype is automatically generated by mkRoute

Methods

dispatcher :: Handler master

Used internally. However needs to be exported for TH to work.

class Eq (Route a) => RenderRoute a where

Associated Types

data Route a

The type-safe URLs associated with a site argument.

Methods

renderRoute

Arguments

:: Route a

-> ([Text], [(Text, Text)])

The path of the URL split on forward slashes, and a list of query parameters with their associated value.

A RenderRoute instance for your site datatype is automatically generated by mkRoute

class RenderRoute a => ParseRoute a where

Methods

parseRoute

Arguments

:: ([Text], [(Text, Text)])

The path of the URL split on forward slashes, and a list of query parameters with their associated value.

-> Maybe (Route a)

A ParseRoute instance for your site datatype is automatically generated by mkRoute

class RenderRoute a => RouteAttrs a where

Methods

routeAttrs

Arguments

:: Route a

-> Set Text

A set of attributes associated with the route.

A RouteAttrs instance for your site datatype is automatically generated by mkRoute

Accessing Request Data

data RequestData

An abstract representation of the request data. You can get the wai request object by using waiReq

waiReq :: RequestData -> Request

Extract the wai Request object from RequestData

nextApp :: RequestData -> Application

Extract the next Application in the stack

runNext :: RequestData -> ResponseHandler

Run the next application in the stack

Run the next application in the stack