Fully-featured GraphQL Server with focus on easy setup, performance & great developer experience
- Easiest way to run a GraphQL server: Sensible defaults & includes everything you need with minimal setup.
- Includes Subscriptions: Built-in support for GraphQL subscriptions using WebSockets.
- Compatible: Works with all GraphQL clients (Apollo, Relay...) and fits seamless in your GraphQL workflow.
graphql-yoga
is based on the following libraries & tools:
express
/apollo-server
: Performant, extensible web server frameworkgraphql-subscriptions
/subscriptions-transport-ws
: GraphQL subscriptions servergraphql.js
/graphql-tools
: GraphQL engine & schema helpersgraphql-playground
: Interactive GraphQL IDE
- GraphQL spec-compliant
- File upload
- GraphQL Subscriptions
- TypeScript typings
- GraphQL Playground
- Extensible via Express middlewares
- Schema directives
- Apollo Tracing
- Accepts both
application/json
andapplication/graphql
content-types - Runs everywhere: Can be deployed via
now
,up
, AWS Lambda, Heroku etc.
yarn add graphql-yoga
Quickstart (Hosted demo)
import { GraphQLServer } from 'graphql-yoga'
// ... or using `require()`
// const { GraphQLServer } = require('graphql-yoga')
const typeDefs = `
type Query {
hello(name: String): String!
}
`
const resolvers = {
Query: {
hello: (_, { name }) => `Hello ${name || 'World'}`,
},
}
const server = new GraphQLServer({ typeDefs, resolvers })
server.start(() => console.log('Server is running on localhost:4000'))
To get started with
graphql-yoga
, follow the instructions in the READMEs of the examples.
The props
argument accepts the following fields:
Key | Type | Default | Note |
---|---|---|---|
typeDefs |
String or Function or DocumentNode or array of previous |
null |
Contains GraphQL type definitions in SDL or file path to type definitions (required if schema is not provided *) |
resolvers |
Object | null |
Contains resolvers for the fields specified in typeDefs (required if schema is not provided *) |
schema |
Object | null |
An instance of GraphQLSchema (required if typeDefs and resolvers are not provided *) |
context |
Object or Function | {} |
Contains custom data being passed through your resolver chain. This can be passed in as an object, or as a Function with the signature (req: ContextParameters) => any ** |
schemaDirectives |
Object | null |
Apollo Server schema directives that allow for transforming schema types, fields, and arguments |
(*) There are two major ways of providing the schema information to the
constructor
:
- Provide
typeDefs
andresolvers
and omit theschema
, in this casegraphql-yoga
will construct theGraphQLSchema
instance usingmakeExecutableSchema
fromgraphql-tools
.- Provide the
schema
directly and omittypeDefs
andresolvers
.
(**) Notice that the
req
argument is an object of the shape{ request, response, connection }
which either carries arequest: Request
property (when it's aQuery
/Mutation
resolver),response: Response
property (when it's aQuery
/Mutation
resolver), or aconnection: SubscriptionOptions
property (when it's aSubscription
resolver).Request
is imported from Express.js.Response
is imported from Express.js aswell.SubscriptionOptions
is from thegraphql-subscriptions
package.SubscriptionOptions
are getting theconnectionParams
automatically injected underSubscriptionOptions.context.[CONNECTION_PARAMETER_NAME]
Here is example of creating a new server:
const typeDefs = `
type Query {
hello(name: String): String!
}
`
const resolvers = {
Query: {
hello: (_, { name }) => `Hello ${name || 'World'}`,
},
}
const server = new GraphQLServer({ typeDefs, resolvers })
Once your GraphQLServer
is instantiated, you can call the start
method on it. It takes two arguments: options
, the options object defined above, and callback
, a function that's invoked right before the server is started. As an example, the callback
can be used to print information that the server has started.
The options
object has the following fields:
Key | Type | Default | Note |
---|---|---|---|
cors |
Object | null |
Contains configuration options for cors |
tracing |
Boolean or TracingOptions | 'http-header' |
Indicates whether Apollo Tracing should be enabled or disabled for your server (if a string is provided, accepted values are: 'enabled' , 'disabled' , 'http-header' ) |
port |
Number or String | 4000 |
Determines the port your server will be listening on (note that you can also specify the port by setting the PORT environment variable) |
endpoint |
String | '/' |
Defines the HTTP endpoint of your server |
subscriptions |
Object or String or false |
'/' |
Defines the subscriptions (websocket) endpoint for your server; accepts an object with subscription server options path , keepAlive , onConnect and onDisconnect ; setting to false disables subscriptions completely |
playground |
String or false |
'/' |
Defines the endpoint where you can invoke the Playground; setting to false disables the playground endpoint |
uploads |
UploadOptions or false or undefined |
null |
Provides information about upload limits; the object can have any combination of the following three keys: maxFieldSize , maxFileSize , maxFiles ; each of these have values of type Number; setting to false disables file uploading |
https |
HttpsOptions or undefined |
undefined |
Enables HTTPS support with a key/cert |
Additionally, the options
object exposes these apollo-server
options:
Key | Type | Note |
---|---|---|
cacheControl |
Boolean | Enable extension that returns Cache Control data in the response |
formatError |
Number | A function to apply to every error before sending the response to clients |
logFunction |
LogFunction | A function called for logging events such as execution times |
rootValue |
any | RootValue passed to GraphQL execution |
validationRules |
Array of functions | Additional GraphQL validation rules to be applied to client-specified queries |
fieldResolver |
GraphQLFieldResolver | Specify a custom default field resolver function |
formatParams |
Function | A function applied to each query in a batch to format parameters before execution |
formatResponse |
Function | A function applied to each response after execution |
debug |
boolean | Print additional debug logging if execution errors occur |
const options = {
port: 8000,
endpoint: '/graphql',
subscriptions: '/subscriptions',
playground: '/playground',
}
server.start(options, ({ port }) => console.log(`Server started, listening on port ${port} for incoming requests.`))
See the original documentation in graphql-subscriptions
.
There are three examples demonstrating how to quickly get started with graphql-yoga
:
- hello-world: Basic setup for building a schema and allowing for a
hello
query. - subscriptions: Basic setup for using subscriptions with a counter that increments every 2 seconds and triggers a subscription.
- fullstack: Fullstack example based on
create-react-app
demonstrating how to query data fromgraphql-yoga
with Apollo Client 2.0.
Once your graphql-yoga
server is running, you can use GraphQL Playground out of the box β typically running on localhost:4000
. (Read here for more information.)
To deploy your graphql-yoga
server with now
, follow these instructions:
- Download Now Desktop
- Navigate to the root directory of your
graphql-yoga
server - Run
now
in your terminal
To deploy your graphql-yoga
server with Heroku, follow these instructions:
- Download and install the Heroku Command Line Interface (previously Heroku Toolbelt)
- Log in to the Heroku CLI with
heroku login
- Navigate to the root directory of your
graphql-yoga
server - Create the Heroku instance by executing
heroku create
- Deploy your GraphQL server by executing
git push heroku master
As mentioned above, graphql-yoga
is built on top of a variety of other packages, such as graphql.js
, express
and apollo-server
. Each of these provides a certain piece of functionality required for building a GraphQL server.
Using these packages individually incurs overhead in the setup process and requires you to write a lot of boilerplate. graphql-yoga
abstracts away the initial complexity and required boilerplate and lets you get started quickly with a set of sensible defaults for your server configuration.
graphql-yoga
is like create-react-app
for building GraphQL servers.
graphql-yoga
is all about convenience and a great "Getting Started" experience by abstracting away the complexity that comes when you're building your own GraphQL server from scratch. It's a pragmatic approach to bootstrap a GraphQL server, much like how create-react-app
removes friction when first starting out with React.
Whenever the defaults of graphql-yoga
are too tight a corset for you, you can simply eject from it and use the tooling it's built upon - there's no lock-in or any other kind of magic going on preventing you from doing this.
The core value of graphql-yoga
is that you don't have to write the boilerplate required to configure your express.js application. However, once you need to add more customized behaviour to your server, the default configuration provided by graphql-yoga
might not suit your use case any more. For example, it might be the case that you want to add more custom middleware to your server, like for logging or error reporting.
For these cases, GraphQLServer
exposes the express.Application
directly via its express
property:
server.express.use(myMiddleware())
Middlewares can also be added specifically to the GraphQL endpoint route, by using:
server.express.post(server.options.endpoint, myMiddleware())
Any middlewares you add to that route, will be added right before the apollo-server-express
middleware.
Join our Slack community if you run into issues or have questions. We love talking to you!