graphql schemas and resolvers with auth

server.js

'use strict'

const Fastify = require('fastify')
const mercurius = require('mercurius')
const auth = require('mercurius-auth')

const { ErrorWithProps } = mercurius

const app = Fastify()

const users = [
  {
    id: '1',
    name: 'John',
    username: '@john',
    password: '123'
  },
  {
    id: '2',
    name: 'Jane',
    username: '@jane',
    password: '123'
  }
]

const schema = `
  directive @auth on OBJECT | FIELD_DEFINITION

  extend type Query {
    me(id: ID!): User @auth
    all(name: String): [User]
  }

  type User @key(fields: "id") {
    id: ID!
    name: String
    username: String
    password: String
  }

  input UserInput {
    name: String
    username: String
    password: String
  }

  type Mutation {
    post(input: UserInput): User
    login(username: String, password: String): String
  }
`

const resolvers = {
  Query: {
    me: (parent, { id }, context) => {
      console.log(context)
      return users[id]
    },
    all: (parent, { name }) => {
      return users
    }
  },

  Mutation: {
    post: (parent, { input }) => {
      if (!input.username) {
        throw new ErrorWithProps('Invalid', {
          code: 500,
          message: 'Username not defined'
        })
      }

      return input
    },

    login: (parent, { username, password }) => {
      if (username === 'yuri' && password === '123') {
        return 'token'
      } else {
        throw new ErrorWithProps('Login failed', {
          code: 500,
          message: 'username or password incorrect'
        })        
      }
    }
  }
}

app.register(mercurius, {
  schema,
  resolvers,
  graphiql: 'playground',
  federationMetadata: true
})

app.register(auth, {
  authContext (context) {
    return {
      // context.reply.request.headers['x-user'] 
      identity: true
    }
  },
  async applyPolicy (authDirectiveAST, parent, args, context, info) {
    context.user_id = 10
    return context.auth.identity
  },
  authDirective: 'auth'
})

app.register(require('fastify-cors'), { 
  origin: true
})


app.listen(5000)

// http://localhost:5000/playground

// mutation {
//   post(input: { name: "", username: "" }) {
//     username
//   }
// }

// all {
//   name
// }

//QUERY VARIABLES
//
// query getMe($id: ID!) {
//   me(id: $id) {
//     name
//   }
// }
//
// {
//   "id": 1
// }

// ALIASES
//
// mutation {
//   auth: login(username: "yuri", password: "123")
// }
//

// FRAGMENT
//
// query getUsers {
//   users: all {
//     ...file
//   }
// }
//
// fragment file on User {
//   name
//   username
// }

// DIRECTIVES
//
// query getMe($id: ID!, $permit: Boolean!) {
//   me(id: $id) {
//     name
//     username @skip(if: $permit)
//     password @include(if: $permit)
//   }
// }
//
// {
//   "id": 1,
//   "permit": true
// }