graphql-compose-relay
This is a plugin for graphql-compose, which wraps GraphQL types with Relay specific things, like Node
type and interface, globalId
, clientMutationId
.
Live demo: https://graphql-compose.herokuapp.com/
Installation
npm install graphql graphql-compose graphql-compose-relay --save
Modules graphql
and graphql-compose
are in peerDependencies
, so should be installed explicitly in your app. They have global objects and should not have ability to be installed as submodule.
Example
ObjectTypeComposer
is a graphql-compose utility, that wraps GraphQL types and provide bunch of useful methods for type manipulation.
import composeWithRelay from 'graphql-compose-relay';
import { ObjectTypeComposer } from 'graphql-compose';
import { RootQueryType, UserType } from './my-graphq-object-types';
const rootQueryTypeComposer = new ObjectTypeComposer(RootQueryType);
const userTypeComposer = new ObjectTypeComposer(UserType);
// If passed RootQuery, then will be added only `node` field to this type.
// Via RootQuery.node you may find objects by globally unique ID among all types.
composeWithRelay(rootQueryTypeComposer);
// Other types, like User, will be wrapped with middlewares that:
// - add relay's id field. Field will be added or wrapped to return Relay's globally unique ID.
// - for mutations will be added clientMutationId to input and output objects types
// - this type will be added to NodeInterface for resolving via RootQuery.node
composeWithRelay(userTypeComposer);
That's all!
All mutations resolvers' arguments will be placed into input
field, and added clientMutationId
. If input
fields already exists in resolver, then clientMutationId
will be added to it, rest argument stays untouched. Accepted value via args.input.clientMutationId
will be transfer to payload.clientMutationId
, as Relay required it.
To all wrapped Types with Relay, will be added id
field or wrapped, if it exist already. This field will return globally unique ID among all types in the following format base64(TypeName + ':' + recordId)
.
For RootQuery
will be added node
field, that will resolve by globalId only that types, which you wrap with composeWithRelay
.
All this annoying operations is too fatigue to do by hands. So this middleware done all Relay magic implicitly for you.
Requirements
Method composeWithRelay
accept ObjectTypeComposer
as input argument. So ObjectTypeComposer
should meet following requirements:
- has defined
recordIdFn
(function that from object of this type, returns you id for the globalId construction) - should have
findById
resolver (that will be used byRootQuery.node
)
If something is missing composeWithRelay
throws error.