Safe Haskell	Safe-Inferred
Language	Haskell2010

WebGear.Core.Handler

Description

WebGear handlers

Synopsis

class (ArrowChoice h, ArrowPlus h, ArrowError RouteMismatch h, Monad m) => Handler h m | h -> m where
- arrM :: (a -> m b) -> h a b
- consumeRoute :: h RoutePath a -> h () a
- setDescription :: Description -> h a a
- setSummary :: Summary -> h a a
newtype RoutePath = RoutePath [Text]
data RouteMismatch = RouteMismatch
newtype Description = Description {
- getDescription :: Text
}
newtype Summary = Summary {
- getSummary :: Text
}
type RequestHandler h ts = h (Request `With` ts) Response
type Middleware h tsOut tsIn = RequestHandler h tsIn -> RequestHandler h tsOut
routeMismatch :: ArrowError RouteMismatch h => h a b
unwitnessA :: Handler h m => h (Response `With` ts) Response
(>->) :: Arrow h => h (env, stack) a -> h (env, (a, stack)) b -> h (env, stack) b
(<-<) :: Arrow h => h (env, (a, stack)) b -> h (env, stack) a -> h (env, stack) b

Documentation

class (ArrowChoice h, ArrowPlus h, ArrowError RouteMismatch h, Monad m) => Handler h m | h -> m where Source #

A handler is an arrow with a monadic context.

Handlers have the following capabilities:

Lift a monadic action into a handler arrow.
Implement ArrowChoice typeclass so that conditionals can be used in arrow code.
Implement ArrowPlus for routing requests to specific handlers.
Provide contextual documentation elements - description and summary

Methods

arrM :: (a -> m b) -> h a b Source #

Lift a monadic function to a handler arrow

consumeRoute :: h RoutePath a -> h () a Source #

Consume all remaining path components with an arrow

setDescription :: Description -> h a a Source #

Set a description of a part of an API

setSummary :: Summary -> h a a Source #

Set a summary of a part of an API

newtype RoutePath Source #

Parts of the request path used by the routing machinery

Constructors

RoutePath [Text]

Instances

Instances details

IsList RoutePath Source #
Instance details Defined in WebGear.Core.Handler Associated Types type Item RoutePath # Methods fromList :: [Item RoutePath] -> RoutePath # fromListN :: Int -> [Item RoutePath] -> RoutePath # toList :: RoutePath -> [Item RoutePath] #
Show RoutePath Source #
Instance details Defined in WebGear.Core.Handler Methods showsPrec :: Int -> RoutePath -> ShowS # show :: RoutePath -> String # showList :: [RoutePath] -> ShowS #
Eq RoutePath Source #
Instance details Defined in WebGear.Core.Handler Methods (==) :: RoutePath -> RoutePath -> Bool # (/=) :: RoutePath -> RoutePath -> Bool #
type Item RoutePath Source #
Instance details Defined in WebGear.Core.Handler type Item RoutePath = Text

data RouteMismatch Source #

Indicates that a handler cannot process this route

Constructors

RouteMismatch

Instances

Instances details

Monoid RouteMismatch Source #
Instance details Defined in WebGear.Core.Handler Methods mempty :: RouteMismatch # mappend :: RouteMismatch -> RouteMismatch -> RouteMismatch # mconcat :: [RouteMismatch] -> RouteMismatch #
Semigroup RouteMismatch Source #
Instance details Defined in WebGear.Core.Handler Methods (<>) :: RouteMismatch -> RouteMismatch -> RouteMismatch # sconcat :: NonEmpty RouteMismatch -> RouteMismatch # stimes :: Integral b => b -> RouteMismatch -> RouteMismatch #
Show RouteMismatch Source #
Instance details Defined in WebGear.Core.Handler Methods showsPrec :: Int -> RouteMismatch -> ShowS # show :: RouteMismatch -> String # showList :: [RouteMismatch] -> ShowS #
Eq RouteMismatch Source #
Instance details Defined in WebGear.Core.Handler Methods (==) :: RouteMismatch -> RouteMismatch -> Bool # (/=) :: RouteMismatch -> RouteMismatch -> Bool #
Ord RouteMismatch Source #
Instance details Defined in WebGear.Core.Handler Methods compare :: RouteMismatch -> RouteMismatch -> Ordering # (<) :: RouteMismatch -> RouteMismatch -> Bool # (<=) :: RouteMismatch -> RouteMismatch -> Bool # (>) :: RouteMismatch -> RouteMismatch -> Bool # (>=) :: RouteMismatch -> RouteMismatch -> Bool # max :: RouteMismatch -> RouteMismatch -> RouteMismatch # min :: RouteMismatch -> RouteMismatch -> RouteMismatch #

newtype Description Source #

Description associated with part of an API

Constructors

Description
Fields getDescription :: Text

Instances

Instances details

IsString Description Source #
Instance details Defined in WebGear.Core.Handler Methods fromString :: String -> Description #
Read Description Source #
Instance details Defined in WebGear.Core.Handler Methods readsPrec :: Int -> ReadS Description # readList :: ReadS [Description] # readPrec :: ReadPrec Description # readListPrec :: ReadPrec [Description] #
Show Description Source #
Instance details Defined in WebGear.Core.Handler Methods showsPrec :: Int -> Description -> ShowS # show :: Description -> String # showList :: [Description] -> ShowS #
Eq Description Source #
Instance details Defined in WebGear.Core.Handler Methods (==) :: Description -> Description -> Bool # (/=) :: Description -> Description -> Bool #
Ord Description Source #
Instance details Defined in WebGear.Core.Handler Methods compare :: Description -> Description -> Ordering # (<) :: Description -> Description -> Bool # (<=) :: Description -> Description -> Bool # (>) :: Description -> Description -> Bool # (>=) :: Description -> Description -> Bool # max :: Description -> Description -> Description # min :: Description -> Description -> Description #

newtype Summary Source #

A summary associated with part of an API

Constructors

Summary
Fields getSummary :: Text

Instances

Instances details

IsString Summary Source #
Instance details Defined in WebGear.Core.Handler Methods fromString :: String -> Summary #
Read Summary Source #
Instance details Defined in WebGear.Core.Handler Methods readsPrec :: Int -> ReadS Summary # readList :: ReadS [Summary] # readPrec :: ReadPrec Summary # readListPrec :: ReadPrec [Summary] #
Show Summary Source #
Instance details Defined in WebGear.Core.Handler Methods showsPrec :: Int -> Summary -> ShowS # show :: Summary -> String # showList :: [Summary] -> ShowS #
Eq Summary Source #
Instance details Defined in WebGear.Core.Handler Methods (==) :: Summary -> Summary -> Bool # (/=) :: Summary -> Summary -> Bool #
Ord Summary Source #
Instance details Defined in WebGear.Core.Handler Methods compare :: Summary -> Summary -> Ordering # (<) :: Summary -> Summary -> Bool # (<=) :: Summary -> Summary -> Bool # (>) :: Summary -> Summary -> Bool # (>=) :: Summary -> Summary -> Bool # max :: Summary -> Summary -> Summary # min :: Summary -> Summary -> Summary #

type RequestHandler h ts = h (Request `With` ts) Response Source #

A handler arrow from a witnessed request to response.

type Middleware h tsOut tsIn = RequestHandler h tsIn -> RequestHandler h tsOut Source #

A middleware enhances a RequestHandler and produces another handler.

routeMismatch :: ArrowError RouteMismatch h => h a b Source #

Indicates that the request does not match the current handler.

unwitnessA :: Handler h m => h (Response `With` ts) Response Source #

Lifts unwitness into a handler arrow.

(>->) :: Arrow h => h (env, stack) a -> h (env, (a, stack)) b -> h (env, stack) b infixr 1 Source #

Thread a response through commands from left to right.

For example, an HTTP 200 response with a body and Content-Type header can be generated with:

 (ok200 -< ())
   >-> (resp -> setBody "text/plain" -< (resp, "Hello World"))
   >-> (resp -> unwitnessA -< resp)

(<-<) :: Arrow h => h (env, (a, stack)) b -> h (env, stack) a -> h (env, stack) b infixr 1 Source #

Thread a response through commands from right to left.

For example, an HTTP 200 response with a body and Content-Type header can be generated with:

 (resp -> unwitnessA -< resp)
   (resp - setBody "text/plain" -< (resp, "Hello World"))
   <-< (ok200 -< ())