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Flow Types

This plugin generates Flow types based on your GraphQLSchema.

It generates types for your entire schema: types, input types, enum, interface, scalar and union.

Installation

flow plugin version
Using yarn
yarn add -D @graphql-codegen/flow

API Reference

useFlowExactObjects

type: boolean default: true

Generates Flow types as Exact types.

Usage Examples

generates:
path/to/file.ts:
plugins:
- flow
config:
useFlowExactObjects: false

useFlowReadOnlyTypes

type: boolean default: false

Generates read-only Flow types

Usage Examples

generates:
path/to/file.ts:
plugins:
- flow
config:
useFlowReadOnlyTypes: true

addUnderscoreToArgsType

type: boolean

Adds _ to generated Args types in order to avoid duplicate identifiers.

Usage Examples

With Custom Values
config:
addUnderscoreToArgsType: true

enumValues

type: EnumValuesMap

Overrides the default value of enum values declared in your GraphQL schema. You can also map the entire enum to an external type by providing a string that of module#type.

declarationKind

type: DeclarationKindConfig | string (values: abstract class, class, interface, type)

Overrides the default output for various GraphQL elements.

Usage Examples

Override all declarations
config:
declarationKind: 'interface'
Override only specific declarations
config:
declarationKind:
type: 'interface'
input: 'interface'

enumPrefix

type: boolean default: true

Allow you to disable prefixing for generated enums, works in combination with typesPrefix.

Usage Examples

Disable enum prefixes
config:
typesPrefix: I
enumPrefix: false

fieldWrapperValue

type: string default: T

Allow you to add wrapper for field type, use T as the generic value. Make sure to set wrapFieldDefinitions to true in order to make this flag work.

Usage Examples

Allow Promise
generates:
path/to/file.ts:
plugins:
- typescript
config:
wrapFieldDefinitions: true
fieldWrapperValue: T | Promise<T>

wrapFieldDefinitions

type: boolean default: false

Set the to true in order to wrap field definitions with FieldWrapper. This is useful to allow return types such as Promises and functions.

Usage Examples

Enable wrapping fields
generates:
path/to/file.ts:
plugins:
- typescript
config:
wrapFieldDefinitions: true

onlyOperationTypes

type: boolean default: false

This will cause the generator to emit types for operations only (basically only enums and scalars)

Usage Examples

Override all definition types
generates:
path/to/file.ts:
plugins:
- typescript
config:
onlyOperationTypes: true

ignoreEnumValuesFromSchema

type: boolean default: false

This will cause the generator to ignore enum values defined in GraphQLSchema

Usage Examples

Ignore enum values from schema
generates:
path/to/file.ts:
plugins:
- typescript
config:
ignoreEnumValuesFromSchema: true

scalars

type: ScalarsMap

Extends or overrides the built-in scalars and custom GraphQL scalars to a custom type.

namingConvention

type: NamingConvention default: change-case-all#pascalCase

Allow you to override the naming convention of the output. You can either override all namings, or specify an object with specific custom naming convention per output. The format of the converter must be a valid module#method. Allowed values for specific output are: typeNames, enumValues. You can also use "keep" to keep all GraphQL names as-is. Additionally you can set transformUnderscore to true if you want to override the default behavior, which is to preserves underscores.

Available case functions in change-case-all are camelCase, capitalCase, constantCase, dotCase, headerCase, noCase, paramCase, pascalCase, pathCase, sentenceCase, snakeCase, lowerCase, localeLowerCase, lowerCaseFirst, spongeCase, titleCase, upperCase, localeUpperCase and upperCaseFirst See more

typesPrefix

type: string default: ``

Prefixes all the generated types.

Usage Examples

config:
typesPrefix: I

typesSuffix

type: string default: ``

Suffixes all the generated types.

Usage Examples

config:
typesSuffix: I

skipTypename

type: boolean default: false

Does not add __typename to the generated types, unless it was specified in the selection set.

Usage Examples

config:
skipTypename: true

nonOptionalTypename

type: boolean default: false

Automatically adds __typename field to the generated types, even when they are not specified in the selection set, and makes it non-optional

Usage Examples

config:
nonOptionalTypename: true

useTypeImports

type: boolean default: false

Will use import type {} rather than import {} when importing only types. This gives compatibility with TypeScript's "importsNotUsedAsValues": "error" option