$ mkdir graphql-yoga-quickstart
$ cd graphql-yoga-quickstart
$ yarn init --yes
$ yarn add -D typescript ts-node-dev

$ yarn add graphql @graphql-yoga/node

{
  "name": "graphql-yoga-quickstart",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "devDependencies": {
    "ts-node-dev": "^1.1.8",
    "typescript": "^4.6.3"
  },
  "dependencies": {
    "@graphql-yoga/node": "^2.3.0",
    "graphql": "^16.3.0"
  },
  "scripts": {
    "dev": "ts-node-dev src/main.ts"
  }
}

import { createServer } from '@graphql-yoga/node';

// Create your server
const server = createServer({
  schema: {
    typeDefs: /* GraphQL */ `
      type Query {
        hello: String
      }
    `,
    resolvers: {
      Query: {
        hello: () => 'Hello Hello Hello',
      },
    },
  },
});
// start the server and explore http://localhost:4000/graphql
server.start();

$ yarn dev

const server = createServer({
  graphiql: {
    defaultQuery: /* GraphQL */ `
      query {
        hello
      }
    `,
  },
})

const server = createServer({
  graphiql: false,
})

import { createServer } from '@graphql-yoga/node'
import { fetch } from 'cross-undici-fetch'

// Provide your schema
const server = createServer({
  schema: {
    typeDefs: /* GraphQL */ `
      type Query {
        greeting: String!
      }
    `,
    resolvers: {
      Query: {
        greeting: async () => {
          // This service does not exist
          const greeting = await fetch('http://localhost:9876/greeting').then(
            (res) => res.text(),
          )

          return greeting
        },
      },
    },
  },
})

// Start the server and explore http://localhost:4000/graphql
server.start()

{
  greeting
}

{
  "errors": [
    {
      "message": "Unexpected error.",
      "locations": [
        {
          "line": 2,
          "column": 3
        }
      ],
      "path": ["greetings"]
    }
  ],
  "data": null
}

NODE_ENV=development ts-node-dev src/main.ts

{
  "errors": [
    {
      "message": "Unexpected error.",
      "locations": [
        {
          "line": 2,
          "column": 3
        }
      ],
      "path": [
        "greeting"
      ],
+      "extensions": {
+        "originalError": {
+          "message": "fetch failed",
+          "stack": "TypeError: fetch failed\n    at Object.processResponse (/Users/satoshi/Documents/nbstsh/graphql-yoga-quickstart/node_modules/undici/lib/fetch/index.js:200:23)\n    at /Users/satoshi/Documents/nbstsh/graphql-yoga-quickstart/node_modules/undici/lib/fetch/index.js:941:38\n    at node:internal/process/task_queues:141:7\n    at AsyncResource.runInAsyncScope (node:async_hooks:199:9)\n    at AsyncResource.runMicrotask (node:internal/process/task_queues:138:8)\n    at processTicksAndRejections (node:internal/process/task_queues:96:5)"
+        }
+      }
    }
  ],
  "data": null
}

import { createServer } from '@graphql-yoga/node'

// Provide your schema
const server = createServer({
  schema: {
    typeDefs: /* GraphQL */ `
      scalar File

      type Mutation {
        readTextFile(file: File!): String!
      }
    `,
    resolvers: {
      Mutation: {
        /**
         * TypeScript type `File` is globally available.
         * You don't need to install/import anything else
         * for both `File` GraphQL Scalar and this type
         */
        readTextFile: async (_, { file }: { file: File }) => {
          const textContent = await file.text()
          return textContent
        },
      },
    },
  },
})
// Start the server and explore http://localhost:4000/graphql
server.start()

import { useGraphQLJit } from '@envelop/graphql-jit'
import { createServer } from '@graphql-yoga/node'

// Provide your schema
const server = createServer({
  schema: {
    typeDefs: /* GraphQL */ `
      type Query {
        greetings: String!
      }
    `,
    resolvers: {
      Query: {
        greetings: () => 'Hello World!',
      },
    },
  },
  plugins: [useGraphQlJit()],
})

// Start the server and explore http://localhost:4000/graphql
server.start()

import { createServer } from '@graphql-yoga/common'

const yoga = createServer()

const response = await yoga.inject({
  document: '{ greetings }',
})

console.assert(response.status === 200, 'Response status should be 200')
const executionResult = await response.json()
console.assert(
  executionResult.data.greetings ===
    'This is the `greetings` field of the root `Query` type',
  `Expected 'This is the `greetings` field of the root `Query` type' but got ${executionResult.data.greetings}`,
)

import { createServer } from '@graphql-yoga/common'

const response = await yoga.fetch('http://localhost:4000/graphql', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    query: '{ greetings }',
  }),
})

console.assert(response.status === 200, 'Response status should be 200')
const executionResult = await response.json()
console.assert(
  executionResult.data.greetings ===
    'This is the `greetings` field of the root `Query` type',
  `Expected 'This is the `greetings` field of the root `Query` type' but got ${executionResult.data.greetings}`,
)

import { createServer } from '@graphql-yoga/node'
import request from 'supertest'
import { deepEqual } from 'assert'

const yoga = createServer()

const response = await request(yoga).post('/graphql').send({
  query: '{ greetings }',
})

deepEqual(response.status, 200)
deepEqual(
  response.body.data.greetings,
  'This is the `greetings` field of the root `Query` type',
)

import { createServer } from '@graphql-yoga/node';

export const server = createServer({
  // others...

  context: async ({ request}) => {
    const user = await getUserByToken(request.headers.get('authorization'))
    return {
      user,
    }
  }
});