Integration with AWS Lambda

import { APIGatewayEvent, APIGatewayProxyResult, Context } from 'aws-lambda'
import { createSchema, createYoga } from 'graphql-yoga'

const yoga = createYoga<{
  event: APIGatewayEvent
  lambdaContext: Context
}>({
  // You need to specify the path to your lambda function
  graphqlEndpoint: '/my-lambda',
  schema: createSchema({
    typeDefs: /* GraphQL */ `
      type Query {
        greetings: String
      }
    `,
    resolvers: {
      Query: {
        greetings: () => 'This is the `greetings` field of the root `Query` type'
      }
    }
  })
})

export async function handler(
  event: APIGatewayEvent,
  lambdaContext: Context
): Promise<APIGatewayProxyResult> {
  const response = await yoga.fetch(
    event.path +
      '?' +
      new URLSearchParams((event.queryStringParameters as Record<string, string>) || {}).toString(),
    {
      method: event.httpMethod,
      headers: event.headers as HeadersInit,
      body: event.body
        ? Buffer.from(event.body, event.isBase64Encoded ? 'base64' : 'utf8')
        : undefined
    },
    {
      event,
      lambdaContext
    }
  )

  const responseHeaders = Object.fromEntries(response.headers.entries())

  return {
    statusCode: response.status,
    headers: responseHeaders,
    body: await response.text(),
    isBase64Encoded: false
  }
}