Language.GraphQL.AST.Document

This module defines an abstract syntax tree for the GraphQL language. It follows closely the structure given in the specification. Please refer to Facebook's GraphQL Specification. for more information.

Documentation

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 (Node Value) Location

Instances

Eq Argument

Defined in Language.GraphQL.AST.Document

Methods

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

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

Show Argument

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Argument -> ShowS

show :: Argument -> String

showList :: [Argument] -> ShowS

newtype ArgumentsDefinition

A list of values passed to a field.

type Person {
  name: String
  picture(width: Int, height: Int): Url
}

Person has two fields, "name" and "picture". "name" doesn't have any arguments, so ArgumentsDefinition contains an empty list. "picture" contains definitions for 2 arguments: "width" and "height".

Constructors

ArgumentsDefinition [InputValueDefinition]

Instances

Eq ArgumentsDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: ArgumentsDefinition -> ArgumentsDefinition -> Bool

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

Show ArgumentsDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> ArgumentsDefinition -> ShowS

show :: ArgumentsDefinition -> String

showList :: [ArgumentsDefinition] -> ShowS

Semigroup ArgumentsDefinition

Defined in Language.GraphQL.AST.Document

Methods

(<>) :: ArgumentsDefinition -> ArgumentsDefinition -> ArgumentsDefinition

sconcat :: NonEmpty ArgumentsDefinition -> ArgumentsDefinition

stimes :: Integral b => b -> ArgumentsDefinition -> ArgumentsDefinition

Monoid ArgumentsDefinition

Defined in Language.GraphQL.AST.Document

Methods

mempty :: ArgumentsDefinition

mappend :: ArgumentsDefinition -> ArgumentsDefinition -> ArgumentsDefinition

mconcat :: [ArgumentsDefinition] -> ArgumentsDefinition

data ConstValue

Constant input value.

Constructors

ConstInt Int32

ConstFloat Double

ConstString Text

ConstBoolean Bool

ConstNull

ConstEnum Name

ConstList [Node ConstValue]

ConstObject [ObjectField ConstValue]

Instances

Eq ConstValue

Defined in Language.GraphQL.AST.Document

Methods

(==) :: ConstValue -> ConstValue -> Bool

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

Show ConstValue

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> ConstValue -> ShowS

show :: ConstValue -> String

showList :: [ConstValue] -> ShowS

data Definition

All kinds of definitions that can occur in a GraphQL document.

Constructors

ExecutableDefinition ExecutableDefinition

TypeSystemDefinition TypeSystemDefinition Location

TypeSystemExtension TypeSystemExtension Location

Instances

Eq Definition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: Definition -> Definition -> Bool

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

Show Definition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Definition -> ShowS

show :: Definition -> String

showList :: [Definition] -> ShowS

newtype Description

GraphQL has built-in capability to document service APIs. Documentation is a GraphQL string that precedes a particular definition and contains Markdown. Any GraphQL definition can be documented this way.

"""
Supported languages.
"""
enum Language {
  English
  EN

  Russian
  RU
}

Constructors

Description (Maybe Text)

Instances

Eq Description

Defined in Language.GraphQL.AST.Document

Methods

(==) :: Description -> Description -> Bool

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

Show Description

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Description -> ShowS

show :: Description -> String

showList :: [Description] -> ShowS

data Directive

Directive.

Directives begin with "@", can accept arguments, and can be applied to the most GraphQL elements, providing additional information.

Constructors

Directive Name [Argument] Location

Instances

Eq Directive

Defined in Language.GraphQL.AST.Document

Methods

(==) :: Directive -> Directive -> Bool

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

Show Directive

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Directive -> ShowS

show :: Directive -> String

showList :: [Directive] -> ShowS

type Document = NonEmpty Definition

GraphQL document.

data EnumValueDefinition

Single value in an enum definition.

enum Direction {
  NORTH
  EAST
  SOUTH
  WEST
}

"NORTH, EAST, SOUTH, and WEST are value definitions of an enum type definition Direction.

Constructors

EnumValueDefinition Description Name [Directive]

Instances

Eq EnumValueDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: EnumValueDefinition -> EnumValueDefinition -> Bool

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

Show EnumValueDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> EnumValueDefinition -> ShowS

show :: EnumValueDefinition -> String

showList :: [EnumValueDefinition] -> ShowS

data ExecutableDefinition

Top-level definition of a document, either an operation or a fragment.

Constructors

DefinitionOperation OperationDefinition

DefinitionFragment FragmentDefinition

Instances

Eq ExecutableDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: ExecutableDefinition -> ExecutableDefinition -> Bool

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

Show ExecutableDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> ExecutableDefinition -> ShowS

show :: ExecutableDefinition -> String

showList :: [ExecutableDefinition] -> ShowS

data Field

The only required property of a field is its name. Optionally it can also have an alias, arguments, directives and a list of subfields.

In the following query "user" is a field with two subfields, "id" and "name":

{
  user {
    id
    name
  }
}

Constructors

Field (Maybe Name) Name [Argument] [Directive] SelectionSetOpt Location

Instances

Eq Field

Defined in Language.GraphQL.AST.Document

Methods

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

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

Show Field

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Field -> ShowS

show :: Field -> String

showList :: [Field] -> ShowS

data FieldDefinition

Definition of a single field in a type.

type Person {
  name: String
  picture(width: Int, height: Int): Url
}

"name" and "picture", including their arguments and types, are field definitions.

Constructors

FieldDefinition Description Name ArgumentsDefinition Type [Directive]

Instances

Eq FieldDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: FieldDefinition -> FieldDefinition -> Bool

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

Show FieldDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> FieldDefinition -> ShowS

show :: FieldDefinition -> String

showList :: [FieldDefinition] -> ShowS

data FragmentDefinition

Fragment definition.

Constructors

FragmentDefinition Name TypeCondition [Directive] SelectionSet Location

Instances

Eq FragmentDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: FragmentDefinition -> FragmentDefinition -> Bool

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

Show FragmentDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> FragmentDefinition -> ShowS

show :: FragmentDefinition -> String

showList :: [FragmentDefinition] -> ShowS

data FragmentSpread

A fragment spread refers to a fragment defined outside the operation and is expanded at the execution time.

{
  user {
    ...userFragment
  }
}

fragment userFragment on UserType {
  id
  name
}

Constructors

FragmentSpread Name [Directive] Location

Instances

Eq FragmentSpread

Defined in Language.GraphQL.AST.Document

Methods

(==) :: FragmentSpread -> FragmentSpread -> Bool

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

Show FragmentSpread

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> FragmentSpread -> ShowS

show :: FragmentSpread -> String

showList :: [FragmentSpread] -> ShowS

newtype ImplementsInterfaces t

Defines a list of interfaces implemented by the given object type.

type Business implements NamedEntity & ValuedEntity {
  name: String
}

Here the object type Business implements two interfaces: NamedEntity and ValuedEntity.

Constructors

ImplementsInterfaces (t NamedType)

Instances

Foldable t => Eq (ImplementsInterfaces t)

Defined in Language.GraphQL.AST.Document

Methods

(==) :: ImplementsInterfaces t -> ImplementsInterfaces t -> Bool

(/=) :: ImplementsInterfaces t -> ImplementsInterfaces t -> Bool

Foldable t => Show (ImplementsInterfaces t)

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> ImplementsInterfaces t -> ShowS

show :: ImplementsInterfaces t -> String

showList :: [ImplementsInterfaces t] -> ShowS

data InlineFragment

Inline fragments don't have any name and the type condition ("on UserType") is optional.

{
  user {
    ... on UserType {
      id
      name
    }
}

Constructors

InlineFragment (Maybe TypeCondition) [Directive] SelectionSet Location

Instances

Eq InlineFragment

Defined in Language.GraphQL.AST.Document

Methods

(==) :: InlineFragment -> InlineFragment -> Bool

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

Show InlineFragment

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> InlineFragment -> ShowS

show :: InlineFragment -> String

showList :: [InlineFragment] -> ShowS

data InputValueDefinition

Defines an input value.

• Input values can define field arguments, see ArgumentsDefinition.
• They can also be used as field definitions in an input type.

input Point2D {
  x: Float
  y: Float
}

The input type Point2D contains two value definitions: "x" and "y".

Constructors

InputValueDefinition Description Name Type (Maybe (Node ConstValue)) [Directive]

Instances

Eq InputValueDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: InputValueDefinition -> InputValueDefinition -> Bool

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

Show InputValueDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> InputValueDefinition -> ShowS

show :: InputValueDefinition -> String

showList :: [InputValueDefinition] -> ShowS

data Location

Error location, line and column.

Constructors

Location

Fields

• line :: Word
• column :: Word

Instances

Eq Location

Defined in Language.GraphQL.AST.Document

Methods

(==) :: Location -> Location -> Bool

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

Ord Location

Defined in Language.GraphQL.AST.Document

Methods

compare :: Location -> Location -> Ordering

(<) :: Location -> Location -> Bool

(<=) :: Location -> Location -> Bool

(>) :: Location -> Location -> Bool

(>=) :: Location -> Location -> Bool

max :: Location -> Location -> Location

min :: Location -> Location -> Location

Show Location

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Location -> ShowS

show :: Location -> String

showList :: [Location] -> ShowS

type Name = Text

Name.

type NamedType = Name

Represents type names.

data Node a

Contains some tree node with a location.

Constructors

Node

Fields

• node :: a
• location :: Location

Instances

Functor Node

Defined in Language.GraphQL.AST.Document

Methods

fmap :: (a -> b) -> Node a -> Node b

(<$) :: a -> Node b -> Node a

Eq a => Eq (Node a)

Defined in Language.GraphQL.AST.Document

Methods

(==) :: Node a -> Node a -> Bool

(/=) :: Node a -> Node a -> Bool

Show a => Show (Node a)

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Node a -> ShowS

show :: Node a -> String

showList :: [Node a] -> ShowS

data NonNullType

Helper type to represent Non-Null types and lists of such types.

Constructors

NonNullTypeNamed Name

NonNullTypeList Type

Instances

Eq NonNullType

Defined in Language.GraphQL.AST.Document

Methods

(==) :: NonNullType -> NonNullType -> Bool

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

Show NonNullType

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> NonNullType -> ShowS

show :: NonNullType -> String

showList :: [NonNullType] -> ShowS

data ObjectField a

Key-value pair.

A list of ObjectFields represents a GraphQL object type.

Constructors

ObjectField

Fields

• name :: Name
• value :: Node a
• location :: Location

Instances

Functor ObjectField

Defined in Language.GraphQL.AST.Document

Methods

fmap :: (a -> b) -> ObjectField a -> ObjectField b

(<$) :: a -> ObjectField b -> ObjectField a

Eq a => Eq (ObjectField a)

Defined in Language.GraphQL.AST.Document

Methods

(==) :: ObjectField a -> ObjectField a -> Bool

(/=) :: ObjectField a -> ObjectField a -> Bool

Show a => Show (ObjectField a)

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> ObjectField a -> ShowS

show :: ObjectField a -> String

showList :: [ObjectField a] -> ShowS

data OperationDefinition

Operation definition.

Constructors

SelectionSet SelectionSet Location

OperationDefinition OperationType (Maybe Name) [VariableDefinition] [Directive] SelectionSet Location

Instances

Eq OperationDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: OperationDefinition -> OperationDefinition -> Bool

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

Show OperationDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> OperationDefinition -> ShowS

show :: OperationDefinition -> String

showList :: [OperationDefinition] -> ShowS

data OperationType

GraphQL has 3 operation types:

• query - a read-only fetch.
• mutation - a write operation followed by a fetch.
• subscription - a long-lived request that fetches data in response to source events.

Constructors

Query

Mutation

Subscription

Instances

Eq OperationType

Defined in Language.GraphQL.AST.Document

Methods

(==) :: OperationType -> OperationType -> Bool

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

Show OperationType

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> OperationType -> ShowS

show :: OperationType -> String

showList :: [OperationType] -> ShowS

data OperationTypeDefinition

Root operation type definition.

Defining root operation types is not required since they have defaults. So the default query root type is Query, and the default mutation root type is Mutation. But these defaults can be changed for a specific schema. In the following code the query root type is changed to MyQueryRootType, and the mutation root type to MyMutationRootType:

schema {
  query: MyQueryRootType
  mutation: MyMutationRootType
}

Constructors

OperationTypeDefinition OperationType NamedType

Instances

Eq OperationTypeDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: OperationTypeDefinition -> OperationTypeDefinition -> Bool

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

Show OperationTypeDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> OperationTypeDefinition -> ShowS

show :: OperationTypeDefinition -> String

showList :: [OperationTypeDefinition] -> ShowS

data SchemaExtension

Extension of the schema definition by further operations or directives.

Constructors

SchemaOperationExtension [Directive] (NonEmpty OperationTypeDefinition)

SchemaDirectivesExtension (NonEmpty Directive)

Instances

Eq SchemaExtension

Defined in Language.GraphQL.AST.Document

Methods

(==) :: SchemaExtension -> SchemaExtension -> Bool

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

Show SchemaExtension

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> SchemaExtension -> ShowS

show :: SchemaExtension -> String

showList :: [SchemaExtension] -> ShowS

data Selection

Selection is a single entry in a selection set. It can be a single Field, FragmentSpread or an InlineFragment.

Constructors

FieldSelection Field

FragmentSpreadSelection FragmentSpread

InlineFragmentSelection InlineFragment

Instances

Eq Selection

Defined in Language.GraphQL.AST.Document

Methods

(==) :: Selection -> Selection -> Bool

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

Show Selection

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Selection -> ShowS

show :: Selection -> String

showList :: [Selection] -> ShowS

type SelectionSet = NonEmpty Selection

"Top-level" selection, selection on an operation or fragment.

type SelectionSetOpt = [Selection]

Field selection.

data Type

Type representation.

Constructors

TypeNamed Name

TypeList Type

TypeNonNull NonNullType

Instances

Eq Type

Defined in Language.GraphQL.AST.Document

Methods

(==) :: Type -> Type -> Bool

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

Show Type

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Type -> ShowS

show :: Type -> String

showList :: [Type] -> ShowS

type TypeCondition = Name

Type condition.

data TypeDefinition

Type definitions describe various user-defined types.

Constructors

ScalarTypeDefinition Description Name [Directive]

ObjectTypeDefinition Description Name (ImplementsInterfaces []) [Directive] [FieldDefinition]

InterfaceTypeDefinition Description Name [Directive] [FieldDefinition]

UnionTypeDefinition Description Name [Directive] (UnionMemberTypes [])

EnumTypeDefinition Description Name [Directive] [EnumValueDefinition]

InputObjectTypeDefinition Description Name [Directive] [InputValueDefinition]

Instances

Eq TypeDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: TypeDefinition -> TypeDefinition -> Bool

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

Show TypeDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> TypeDefinition -> ShowS

show :: TypeDefinition -> String

showList :: [TypeDefinition] -> ShowS

data TypeExtension

Extensions for custom, already defined types.

Constructors

ScalarTypeExtension Name (NonEmpty Directive)

ObjectTypeFieldsDefinitionExtension Name (ImplementsInterfaces []) [Directive] (NonEmpty FieldDefinition)

ObjectTypeDirectivesExtension Name (ImplementsInterfaces []) (NonEmpty Directive)

ObjectTypeImplementsInterfacesExtension Name (ImplementsInterfaces NonEmpty)

InterfaceTypeFieldsDefinitionExtension Name [Directive] (NonEmpty FieldDefinition)

InterfaceTypeDirectivesExtension Name (NonEmpty Directive)

UnionTypeUnionMemberTypesExtension Name [Directive] (UnionMemberTypes NonEmpty)

UnionTypeDirectivesExtension Name (NonEmpty Directive)

EnumTypeEnumValuesDefinitionExtension Name [Directive] (NonEmpty EnumValueDefinition)

EnumTypeDirectivesExtension Name (NonEmpty Directive)

InputObjectTypeInputFieldsDefinitionExtension Name [Directive] (NonEmpty InputValueDefinition)

InputObjectTypeDirectivesExtension Name (NonEmpty Directive)

Instances

Eq TypeExtension

Defined in Language.GraphQL.AST.Document

Methods

(==) :: TypeExtension -> TypeExtension -> Bool

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

Show TypeExtension

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> TypeExtension -> ShowS

show :: TypeExtension -> String

showList :: [TypeExtension] -> ShowS

data TypeSystemDefinition

Type system can define a schema, a type or a directive.

schema {
  query: Query
}

directive example on FIELD_DEFINITION

type Query {
  field: String example
}

This example defines a custom directive "@example", which is applied to a field definition of the type definition Query. On the top the schema is defined by taking advantage of the type Query.

Constructors

SchemaDefinition [Directive] (NonEmpty OperationTypeDefinition)

TypeDefinition TypeDefinition

DirectiveDefinition Description Name ArgumentsDefinition (NonEmpty DirectiveLocation)

Instances

Eq TypeSystemDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: TypeSystemDefinition -> TypeSystemDefinition -> Bool

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

Show TypeSystemDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> TypeSystemDefinition -> ShowS

show :: TypeSystemDefinition -> String

showList :: [TypeSystemDefinition] -> ShowS

data TypeSystemExtension

Extension for a type system definition. Only schema and type definitions can be extended.

Constructors

SchemaExtension SchemaExtension

TypeExtension TypeExtension

Instances

Eq TypeSystemExtension

Defined in Language.GraphQL.AST.Document

Methods

(==) :: TypeSystemExtension -> TypeSystemExtension -> Bool

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

Show TypeSystemExtension

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> TypeSystemExtension -> ShowS

show :: TypeSystemExtension -> String

showList :: [TypeSystemExtension] -> ShowS

newtype UnionMemberTypes t

List of types forming a union.

union SearchResult = Person | Photo

Person and Photo are member types of the union SearchResult.

Constructors

UnionMemberTypes (t NamedType)

Instances

Foldable t => Eq (UnionMemberTypes t)

Defined in Language.GraphQL.AST.Document

Methods

(==) :: UnionMemberTypes t -> UnionMemberTypes t -> Bool

(/=) :: UnionMemberTypes t -> UnionMemberTypes t -> Bool

Foldable t => Show (UnionMemberTypes t)

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> UnionMemberTypes t -> ShowS

show :: UnionMemberTypes t -> String

showList :: [UnionMemberTypes t] -> ShowS

data Value

Input value (literal or variable).

Constructors

Variable Name

Int Int32

Float Double

String Text

Boolean Bool

Null

Enum Name

List [Node Value]

Object [ObjectField Value]

Instances

Eq Value

Defined in Language.GraphQL.AST.Document

Methods

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

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

Show Value

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> Value -> ShowS

show :: Value -> String

showList :: [Value] -> ShowS

data VariableDefinition

Variable definition.

Each operation can include a list of variables:

query (protagonist: String = "Zarathustra") {
  getAuthor(protagonist: $protagonist)
}

This query defines an optional variable protagonist of type String, its default value is "Zarathustra". If no default value is defined and no value is provided, a variable can still be null if its type is nullable.

Variables are usually passed along with the query, but not in the query itself. They make queries reusable.

Constructors

VariableDefinition Name Type (Maybe (Node ConstValue)) Location

Instances

Eq VariableDefinition

Defined in Language.GraphQL.AST.Document

Methods

(==) :: VariableDefinition -> VariableDefinition -> Bool

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

Show VariableDefinition

Defined in Language.GraphQL.AST.Document

Methods

showsPrec :: Int -> VariableDefinition -> ShowS

show :: VariableDefinition -> String

showList :: [VariableDefinition] -> ShowS

escape :: Char -> String

Escapes a single character according to the GraphQL escaping rules for double-quoted string values.

Characters, that should be escaped, are written as escaped characters with a backslash or Unicode with an "\u". Other characters are returned as strings.