Language.GraphQL.Schema

This module provides a representation of a GraphQL Schema in addition to functions for defining and manipulating schemas.

Documentation

data Resolver m

Resolves a Field into an Aeson.Value with error information (or empty). m is usually expected to be an instance of 'MonadIO.

type Schema m = NonEmpty (Resolver m)

Deprecated: Use NonEmpty (Resolver m) instead

A GraphQL schema. m is usually expected to be an instance of MonadIO.

type Subs = Name -> Maybe Value

Variable substitution function.

object :: MonadIO m => Name -> ActionT m [Resolver m] -> Resolver m

Create a new Resolver with the given Name from the given Resolvers.

objectA :: MonadIO m => Name -> (Arguments -> ActionT m [Resolver m]) -> Resolver m

Like object but also taking Arguments.

scalar :: (MonadIO m, ToJSON a) => Name -> ActionT m a -> Resolver m

A scalar represents a primitive value, like a string or an integer.

scalarA :: (MonadIO m, ToJSON a) => Name -> (Arguments -> ActionT m a) -> Resolver m

Like scalar but also taking Arguments.

enum :: MonadIO m => Name -> ActionT m [Text] -> Resolver m

Deprecated: Use scalar instead

enumA :: MonadIO m => Name -> (Arguments -> ActionT m [Text]) -> Resolver m

Deprecated: Use scalarA instead

resolve :: MonadIO m => [Resolver m] -> Fields -> CollectErrsT m Value

Takes a list of Resolvers and a list of Fields and applies each Resolver to each Field. Resolves into a value containing the resolved Field, or a null value and error information.

wrappedEnum :: MonadIO m => Name -> ActionT m (Wrapping [Text]) -> Resolver m

Deprecated: Use wrappedScalar instead

wrappedEnumA :: MonadIO m => Name -> (Arguments -> ActionT m (Wrapping [Text])) -> Resolver m

Deprecated: Use wrappedScalarA instead

wrappedObject :: MonadIO m => Name -> ActionT m (Wrapping [Resolver m]) -> Resolver m

Like object but can be null or a list of objects.

wrappedObjectA :: MonadIO m => Name -> (Arguments -> ActionT m (Wrapping [Resolver m])) -> Resolver m

Like object but also taking Arguments and can be null or a list of objects.

wrappedScalar :: (MonadIO m, ToJSON a) => Name -> ActionT m (Wrapping a) -> Resolver m

Like scalar but can be null or a list of scalars.

wrappedScalarA :: (MonadIO m, ToJSON a) => Name -> (Arguments -> ActionT m (Wrapping a)) -> Resolver m

Lika scalar but also taking Arguments and can be null or a list of scalars.

AST Reexports

data Field

A single GraphQL field.

Only required property of a field, is its name. Optionally it can also have an alias, arguments or a list of subfields.

Given the following query:

{
  zuck: user(id: 4) {
    id
    name
  }
}

• "user", "id" and "name" are field names.
• "user" has two subfields, "id" and "name".
• "zuck" is an alias for "user". "id" and "name" have no aliases.
• "id: 4" is an argument for "name". "id" and "name don't have any arguments.

Instances

Eq Field

Defined in Language.GraphQL.AST.Core

Methods

(==) :: Field -> Field -> Bool

(/=) :: Field -> Field -> Bool

Show Field

Defined in Language.GraphQL.AST.Core

Methods

showsPrec :: Int -> Field -> ShowS

show :: Field -> String

showList :: [Field] -> ShowS

data Argument

Single argument.

{
  user(id: 4) {
    name
  }
}

Here "id" is an argument for the field "user" and its value is 4.

Constructors

Argument Name Value

Instances

Eq Argument

Defined in Language.GraphQL.AST.Core

Methods

(==) :: Argument -> Argument -> Bool

(/=) :: Argument -> Argument -> Bool

Show Argument

Defined in Language.GraphQL.AST.Core

Methods

showsPrec :: Int -> Argument -> ShowS

show :: Argument -> String

showList :: [Argument] -> ShowS

data Value

Represents accordingly typed GraphQL values.

Constructors

ValueInt Int32

ValueFloat Double

ValueString Text

ValueBoolean Bool

ValueNull

ValueEnum Name

ValueList [Value]

ValueObject [ObjectField]

Instances

Eq Value

Defined in Language.GraphQL.AST.Core

Methods

(==) :: Value -> Value -> Bool

(/=) :: Value -> Value -> Bool

Show Value

Defined in Language.GraphQL.AST.Core

Methods

showsPrec :: Int -> Value -> ShowS

show :: Value -> String

showList :: [Value] -> ShowS

IsString Value

Defined in Language.GraphQL.AST.Core

Methods

fromString :: String -> Value