Yesod.Core.Json

Convert from a JSON value

defaultLayoutJson

Arguments

:: (Yesod site, ToJSON a)

=> WidgetT site IO ()

HTML

-> HandlerT site IO a

JSON

-> HandlerT site IO TypedContent

Provide both an HTML and JSON representation for a piece of data, using the default layout for the HTML output (defaultLayout).

Since: 0.3.0

jsonToRepJson :: (Monad m, ToJSON a) => a -> m Value

Deprecated: Use returnJson instead

Wraps a data type in a RepJson. The data type must support conversion to JSON via ToJSON.

Since: 0.3.0

returnJson :: (Monad m, ToJSON a) => a -> m Value

Convert a value to a JSON representation via aeson's toJSON function.

Since 1.2.1

provideJson :: (Monad m, ToJSON a) => a -> Writer (Endo [ProvidedRep m]) ()

Provide a JSON representation for usage with selectReps, using aeson's toJSON function to perform the conversion.

Since 1.2.1

Convert to a JSON value

parseJsonBody :: (MonadHandler m, FromJSON a) => m (Result a)

Parse the request body to a data type as a JSON value. The data type must support conversion from JSON via FromJSON. If you want the raw JSON value, just ask for a Result Value.

Note that this function will consume the request body. As such, calling it twice will result in a parse error on the second call, since the request body will no longer be available.

Since: 0.3.0

parseJsonBody_ :: (MonadHandler m, FromJSON a) => m a

Deprecated: Use requireJsonBody instead

Same as parseJsonBody, but return an invalid args response on a parse error.

requireJsonBody :: (MonadHandler m, FromJSON a) => m a

Same as parseJsonBody, but return an invalid args response on a parse error.

Produce JSON values

data Value :: *

Constructors

Object !Object

Array !Array

String !Text

Number !Scientific

Bool !Bool

Null

Instances

Eq Value

Data Value

Show Value

IsString Value

NFData Value

Hashable Value

ToJavascript Value

ToJSON Value

FromJSON Value

ToTypedContent Value

HasContentType Value

ToContent Value

Typeable * Value

class ToJSON a where

Minimal complete definition

Nothing

Methods

toJSON :: a -> Value

Instances

ToJSON Bool

ToJSON Char

ToJSON Double

ToJSON Float

ToJSON Int

ToJSON Int8

ToJSON Int16

ToJSON Int32

ToJSON Int64

ToJSON Integer

ToJSON Word

ToJSON Word8

ToJSON Word16

ToJSON Word32

ToJSON Word64

ToJSON ()

ToJSON IntSet

ToJSON ZonedTime

ToJSON UTCTime

ToJSON Text

ToJSON Text

ToJSON Value

ToJSON Number

ToJSON Scientific

ToJSON DotNetTime

ToJSON [Char]

ToJSON a => ToJSON [a]

ToJSON (Ratio Integer)

HasResolution a => ToJSON (Fixed a)

ToJSON a => ToJSON (Dual a)

ToJSON a => ToJSON (First a)

ToJSON a => ToJSON (Last a)

ToJSON a => ToJSON (Maybe a)

ToJSON a => ToJSON (IntMap a)

ToJSON a => ToJSON (Set a)

ToJSON v => ToJSON (Tree v)

(Prim a, ToJSON a) => ToJSON (Vector a)

(Vector Vector a, ToJSON a) => ToJSON (Vector a)

ToJSON a => ToJSON (Vector a)

(Storable a, ToJSON a) => ToJSON (Vector a)

ToJSON a => ToJSON (HashSet a)

(ToJSON a, ToJSON b) => ToJSON (Either a b)

(ToJSON a, ToJSON b) => ToJSON (a, b)

ToJSON v => ToJSON (Map String v)

ToJSON v => ToJSON (Map Text v)

ToJSON v => ToJSON (Map Text v)

ToJSON v => ToJSON (HashMap String v)

ToJSON v => ToJSON (HashMap Text v)

ToJSON v => ToJSON (HashMap Text v)

(ToJSON a, ToJSON b, ToJSON c) => ToJSON (a, b, c)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d) => ToJSON (a, b, c, d)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e) => ToJSON (a, b, c, d, e)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f) => ToJSON (a, b, c, d, e, f)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g) => ToJSON (a, b, c, d, e, f, g)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h) => ToJSON (a, b, c, d, e, f, g, h)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i) => ToJSON (a, b, c, d, e, f, g, h, i)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j) => ToJSON (a, b, c, d, e, f, g, h, i, j)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k) => ToJSON (a, b, c, d, e, f, g, h, i, j, k)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l) => ToJSON (a, b, c, d, e, f, g, h, i, j, k, l)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l, ToJSON m) => ToJSON (a, b, c, d, e, f, g, h, i, j, k, l, m)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l, ToJSON m, ToJSON n) => ToJSON (a, b, c, d, e, f, g, h, i, j, k, l, m, n)

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l, ToJSON m, ToJSON n, ToJSON o) => ToJSON (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)

class FromJSON a where

Minimal complete definition

Nothing

Methods

parseJSON :: Value -> Parser a

Instances

FromJSON Bool

FromJSON Char

FromJSON Double

FromJSON Float

FromJSON Int

FromJSON Int8

FromJSON Int16

FromJSON Int32

FromJSON Int64

FromJSON Integer

FromJSON Word

FromJSON Word8

FromJSON Word16

FromJSON Word32

FromJSON Word64

FromJSON ()

FromJSON IntSet

FromJSON ZonedTime

FromJSON UTCTime

FromJSON Text

FromJSON Text

FromJSON Value

FromJSON Number

FromJSON Scientific

FromJSON DotNetTime

FromJSON [Char]

FromJSON a => FromJSON [a]

FromJSON (Ratio Integer)

HasResolution a => FromJSON (Fixed a)

FromJSON a => FromJSON (Dual a)

FromJSON a => FromJSON (First a)

FromJSON a => FromJSON (Last a)

FromJSON a => FromJSON (Maybe a)

FromJSON a => FromJSON (IntMap a)

(Ord a, FromJSON a) => FromJSON (Set a)

FromJSON v => FromJSON (Tree v)

(Prim a, FromJSON a) => FromJSON (Vector a)

(Vector Vector a, FromJSON a) => FromJSON (Vector a)

FromJSON a => FromJSON (Vector a)

(Storable a, FromJSON a) => FromJSON (Vector a)

(Eq a, Hashable a, FromJSON a) => FromJSON (HashSet a)

(FromJSON a, FromJSON b) => FromJSON (Either a b)

(FromJSON a, FromJSON b) => FromJSON (a, b)

FromJSON v => FromJSON (Map String v)

FromJSON v => FromJSON (Map Text v)

FromJSON v => FromJSON (Map Text v)

FromJSON v => FromJSON (HashMap String v)

FromJSON v => FromJSON (HashMap Text v)

FromJSON v => FromJSON (HashMap Text v)

(FromJSON a, FromJSON b, FromJSON c) => FromJSON (a, b, c)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d) => FromJSON (a, b, c, d)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e) => FromJSON (a, b, c, d, e)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f) => FromJSON (a, b, c, d, e, f)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g) => FromJSON (a, b, c, d, e, f, g)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h) => FromJSON (a, b, c, d, e, f, g, h)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i) => FromJSON (a, b, c, d, e, f, g, h, i)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j) => FromJSON (a, b, c, d, e, f, g, h, i, j)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k) => FromJSON (a, b, c, d, e, f, g, h, i, j, k)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l) => FromJSON (a, b, c, d, e, f, g, h, i, j, k, l)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l, FromJSON m) => FromJSON (a, b, c, d, e, f, g, h, i, j, k, l, m)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l, FromJSON m, FromJSON n) => FromJSON (a, b, c, d, e, f, g, h, i, j, k, l, m, n)

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l, FromJSON m, FromJSON n, FromJSON o) => FromJSON (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)

array :: ToJSON a => [a] -> Value

Convert a list of values to an Array.

object :: [Pair] -> Value

(.=) :: ToJSON a => Text -> a -> Pair

(.:) :: FromJSON a => Object -> Text -> Parser a

Convenience functions

jsonOrRedirect

Arguments

:: (MonadHandler m, ToJSON a)

=> Route (HandlerSite m)

Redirect target

-> a

Data to send via JSON

-> m Value

jsonOrRedirect simplifies the scenario where a POST handler sends a different response based on Accept headers:

1. 200 with JSON data if the client prefers application/json (e.g. AJAX, see acceptsJSON).
   1. 3xx otherwise, following the PRG pattern.

acceptsJson :: MonadHandler m => m Bool

Returns True if the client prefers application/json as indicated by the Accept HTTP header.