Safe Haskell	None
Language	Haskell2010

WebGear.Core.Trait.Body

Contents

Traits
Middlewares

Description

Traits and middlewares to handle request and response body payloads.

There are a number of ways to extract a body from a request:

The requestBody middleware attempts to convert the body to a Haskell value or invoke an error handler if that fails.

The jsonRequestBody middleware attempts to convert a JSON formatted body to a Haskell value or invoke an error handler if that fails. It uses the standard "application/json" media type.

The jsonRequestBody' middleware is similar but supports custom media types.

Similarly, there are a number of ways to set a response body:

The easiest option is to use one of respondA, respondJsonA, or respondJsonA' middlewares. These middlewares generate a response from an HTTP status and a response body.

If you need finer control over setting the body, use one of setBody, setBodyWithoutContentType, setJSONBody, setJSONBodyWithoutContentType, or setJSONBody'. These arrows accept a linked response and a body and sets the body in the response. You can generate an input response object using functions from WebGear.Core.Trait.Status module.

Synopsis

newtype Body (t :: Type) = Body (Maybe MediaType)
newtype JSONBody (t :: Type) = JSONBody (Maybe MediaType)
requestBody :: forall t h req. (Get h (Body t) Request, ArrowChoice h) => Maybe MediaType -> h (Linked req Request, Text) Response -> Middleware h req (Body t ': req)
jsonRequestBody' :: forall t h req. (Get h (JSONBody t) Request, ArrowChoice h) => Maybe MediaType -> h (Linked req Request, Text) Response -> Middleware h req (JSONBody t ': req)
jsonRequestBody :: forall t h req. (Get h (JSONBody t) Request, ArrowChoice h) => h (Linked req Request, Text) Response -> Middleware h req (JSONBody t ': req)
respondA :: forall body h. Sets h [Status, Body body, RequiredHeader "Content-Type" Text] Response => Status -> MediaType -> h body (Linked [RequiredHeader "Content-Type" Text, Body body, Status] Response)
respondJsonA :: forall body h. Sets h [Status, JSONBody body, RequiredHeader "Content-Type" Text] Response => Status -> h body (Linked [RequiredHeader "Content-Type" Text, JSONBody body, Status] Response)
respondJsonA' :: forall body h. Sets h [Status, JSONBody body, RequiredHeader "Content-Type" Text] Response => Status -> MediaType -> h body (Linked [RequiredHeader "Content-Type" Text, JSONBody body, Status] Response)
setBody :: forall body a h ts. Sets h [Body body, RequiredHeader "Content-Type" Text] Response => MediaType -> h a (Linked ts Response) -> h (body, a) (Linked (RequiredHeader "Content-Type" Text ': (Body body ': ts)) Response)
setBodyWithoutContentType :: forall body a h ts. Set h (Body body) Response => h a (Linked ts Response) -> h (body, a) (Linked (Body body ': ts) Response)
setJSONBody :: forall body a h ts. Sets h [JSONBody body, RequiredHeader "Content-Type" Text] Response => h a (Linked ts Response) -> h (body, a) (Linked (RequiredHeader "Content-Type" Text ': (JSONBody body ': ts)) Response)
setJSONBodyWithoutContentType :: forall body a h ts. Set h (JSONBody body) Response => h a (Linked ts Response) -> h (body, a) (Linked (JSONBody body ': ts) Response)
setJSONBody' :: forall body a h ts. Sets h [JSONBody body, RequiredHeader "Content-Type" Text] Response => MediaType -> h a (Linked ts Response) -> h (body, a) (Linked (RequiredHeader "Content-Type" Text ': (JSONBody body ': ts)) Response)

Traits

newtype Body (t :: Type) Source #

Request or response body with a type t.

Constructors

Body (Maybe MediaType)

Instances

Instances details

TraitAbsence (Body t) Request Source #
Instance details Defined in WebGear.Core.Trait.Body Associated Types type Absence (Body t) Request Source #
Trait (Body t) Response Source #
Instance details Defined in WebGear.Core.Trait.Body Associated Types type Attribute (Body t) Response Source #
Trait (Body t) Request Source #
Instance details Defined in WebGear.Core.Trait.Body Associated Types type Attribute (Body t) Request Source #
type Absence (Body t) Request Source #
Instance details Defined in WebGear.Core.Trait.Body type Absence (Body t) Request = Text
type Attribute (Body t) Response Source #
Instance details Defined in WebGear.Core.Trait.Body type Attribute (Body t) Response = t
type Attribute (Body t) Request Source #
Instance details Defined in WebGear.Core.Trait.Body type Attribute (Body t) Request = t

newtype JSONBody (t :: Type) Source #

A Trait for converting a JSON formatted body into a value.

Constructors

JSONBody (Maybe MediaType)

Instances

Instances details

TraitAbsence (JSONBody t) Request Source #
Instance details Defined in WebGear.Core.Trait.Body Associated Types type Absence (JSONBody t) Request Source #
Trait (JSONBody t) Response Source #
Instance details Defined in WebGear.Core.Trait.Body Associated Types type Attribute (JSONBody t) Response Source #
Trait (JSONBody t) Request Source #
Instance details Defined in WebGear.Core.Trait.Body Associated Types type Attribute (JSONBody t) Request Source #
type Absence (JSONBody t) Request Source #
Instance details Defined in WebGear.Core.Trait.Body type Absence (JSONBody t) Request = Text
type Attribute (JSONBody t) Response Source #
Instance details Defined in WebGear.Core.Trait.Body type Attribute (JSONBody t) Response = t
type Attribute (JSONBody t) Request Source #
Instance details Defined in WebGear.Core.Trait.Body type Attribute (JSONBody t) Request = t

Middlewares

requestBody Source #

Arguments

:: forall t h req. (Get h (Body t) Request, ArrowChoice h)
=> Maybe MediaType	Optional media type of the body
-> h (Linked req Request, Text) Response	Error handler in case body cannot be retrieved
-> Middleware h req (Body t ': req)

Middleware to extract a request body.

The nextHandler is invoked after successfully extracting the body and the errorHandler is invoked when there is an error.

Usage:

requestBody @t (Just "text/plain") errorHandler nextHandler

jsonRequestBody' Source #

Arguments

:: forall t h req. (Get h (JSONBody t) Request, ArrowChoice h)
=> Maybe MediaType	Optional media type of the body
-> h (Linked req Request, Text) Response	Error handler in case body cannot be retrieved
-> Middleware h req (JSONBody t ': req)

Parse the request body as JSON and convert it to a value of type t.

The nextHandler is invoked when the body is parsed successfully and the errorHandler is invoked when there is a parsing failure.

Usage:

jsonRequestBody @t errorHandler nextHandler

jsonRequestBody Source #

Arguments

:: forall t h req. (Get h (JSONBody t) Request, ArrowChoice h)
=> h (Linked req Request, Text) Response	error handler
-> Middleware h req (JSONBody t ': req)

Same as jsonRequestBody' but with a media type application/json.

respondA Source #

Arguments

:: forall body h. Sets h [Status, Body body, RequiredHeader "Content-Type" Text] Response
=> Status	Response status
-> MediaType	Media type of the response body
-> h body (Linked [RequiredHeader "Content-Type" Text, Body body, Status] Response)

A convenience arrow to generate a response specifying a status and body.

The "Content-Type" header will be set to the specified media type value.

respondJsonA Source #

Arguments

:: forall body h. Sets h [Status, JSONBody body, RequiredHeader "Content-Type" Text] Response
=> Status	Response status
-> h body (Linked [RequiredHeader "Content-Type" Text, JSONBody body, Status] Response)

A convenience arrow to generate a response specifying a status and JSON body.

The "Content-Type" header will be set to "application/json".

respondJsonA' Source #

Arguments

:: forall body h. Sets h [Status, JSONBody body, RequiredHeader "Content-Type" Text] Response
=> Status	Response status
-> MediaType	Media type of the response body
-> h body (Linked [RequiredHeader "Content-Type" Text, JSONBody body, Status] Response)

A convenience arrow to generate a response specifying a status and JSON body.

The "Content-Type" header will be set to the specified media type value.

setBody Source #

Arguments

:: forall body a h ts. Sets h [Body body, RequiredHeader "Content-Type" Text] Response
=> MediaType	The media type of the response body
-> h a (Linked ts Response)
-> h (body, a) (Linked (RequiredHeader "Content-Type" Text ': (Body body ': ts)) Response)

Set the response body along with a media type.

The media type value is used to set the "Content-Type" header in the response.

setBodyWithoutContentType :: forall body a h ts. Set h (Body body) Response => h a (Linked ts Response) -> h (body, a) (Linked (Body body ': ts) Response) Source #

Set the response body without specifying any media type.

setJSONBody :: forall body a h ts. Sets h [JSONBody body, RequiredHeader "Content-Type" Text] Response => h a (Linked ts Response) -> h (body, a) (Linked (RequiredHeader "Content-Type" Text ': (JSONBody body ': ts)) Response) Source #

Set the response body to a JSON value.

The "Content-Type" header will be set to "application/json".

setJSONBodyWithoutContentType :: forall body a h ts. Set h (JSONBody body) Response => h a (Linked ts Response) -> h (body, a) (Linked (JSONBody body ': ts) Response) Source #

Set the response body to a JSON value without specifying any media type.

setJSONBody' Source #

Arguments

:: forall body a h ts. Sets h [JSONBody body, RequiredHeader "Content-Type" Text] Response
=> MediaType	The media type of the response body
-> h a (Linked ts Response)
-> h (body, a) (Linked (RequiredHeader "Content-Type" Text ': (JSONBody body ': ts)) Response)

Set the response body to a JSON value along with a media type.

The media type value is used to set the "Content-Type" header in the response.