GraphQL Server

Now that you have a GraphQL schema, and you understand the concept of GraphQL schema and a GraphQL query, it's time to create a real GraphQL server.

You are going to use the HTTP protocol to serve the GraphQL server, but note that there are other options for serving GraphQL - you can use WebSocket, SSE (Server-Sent Events) and basically any network transport protocol that you wish! (You can find a list of transport implementations at the end of this page)

Creating a GraphQL HTTP Server with Yoga

In this tutorial, we will be using GraphQL Yoga for building our Node.js GraphQL HTTP server.

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Yoga can also run on other platforms, such as Cloudflare Workers or Deno. We recommend checking out the integrations section in our documentation after finishing the tutorial.

You'll need the @graphql-yoga/node package available in your project, so install it using the following command:

yarn add --save-exact @graphql-yoga/node

Now, update src/main.ts to create a simple GraphQL HTTP server on port 4000:

src/main.ts

import { createServer } from '@graphql-yoga/node'
import { schema } from './schema'
 
async function main() {
  const server = createServer({ schema })
  await server.start()
}
 
main()

Now, try to run your server again with npm run dev (or, npm run start).

The output should look similar to the following:

$ cross-env NODE_ENV=development ts-node-dev --exit-child --respawn src/main.ts
[INFO] 15:40:14 ts-node-dev ver. 1.1.8 (using ts-node ver. 9.1.1, typescript ver. 4.5.5)
[2022-02-25 14:40:17.810 +0000] DEBUG (13296 on DESKTOP-U72CGKK): Setting up server.
[2022-02-25 14:40:17.818 +0000] INFO (13296 on DESKTOP-U72CGKK): GraphQL Server running at http://127.0.0.1:4000/graphql.

You'll need the graphql-yoga package available in your project, so install it using the following command:

yarn add --save-exact graphql-yoga

Now, update src/main.ts to create a simple GraphQL HTTP server on port 4000:

src/main.ts

import { createYoga } from 'graphql-yoga'
import { createServer } from 'http'
import { schema } from './schema'
 
function main() {
  const yoga = createYoga({ schema })
  const server = createServer(yoga)
  server.listen(4000, () => {
    console.info('Server is running on http://localhost:4000/graphql')
  })
}
 
main()

Now, try to run your server again with npm run dev (or, npm run start), open your browser and navigate to http://localhost:4000/graphql.

Type in the following operation in the left editor section and press the Play button for executing the operation against the GraphQL server.

query {
  hello
}

Unsurprisingly, the result looks like the following:

{ "data": { "hello": "Hello World!" } }

Of course, it is also possible to send requests to the service without GraphiQL, e.g. by using curl.

Run the following command within your terminal for executing the same query operation.

curl -X POST http://localhost:4000/graphql -H "Content-type: application/json" --data-raw '{"query": "query { hello }"}'

Oh wonder, the result looks like the following:

{ "data": { "hello": "Hello World!" } }

Last updated on September 27, 2022

Getting Started A Simple Query