# Simple-GraphQL Shows query potential of GraphQL.
Courtesy of Web Dev Simplified on YouTube
const express = require('express') const expressGraphQL = require('express-graphql') const { GraphQLSchema, GraphQLObjectType, GraphQLString, GraphQLList, GraphQLInt, GraphQLNonNull } = require('graphql') const app = express()
const authors = [ { id: 1, name: 'J.K. Rowling' }, { id: 2, name: 'J. R. R. Tolkien' }, { id: 3, name: 'Brent Weeks' } ]
const books = [ { id: 1, name: 'Harry Potter and the Chamber of Secrets', authorID: 1 }, { id: 2, name: 'Harry Potter and the Prisoner of Azkhaban', authorID: 1 }, { id: 3, name: 'Harry Potter and the Goblet of Fire', authorID: 1 }, { id: 4, name: 'The Fellowship of the Ring', authorID: 2 }, { id: 5, name: 'The Two Towers', authorID: 2 }, { id: 6, name: 'The Return of the King', authorID: 2 }, { id: 7, name: 'The Way of Shadows', authorID: 3 }, { id: 8, name: 'Beyond the Shadows', authorID: 3 }, ]
const BookType = new GraphQLObjectType({ name: 'Book', description: 'This represents a book written by an author', fields: () => ({ id: { type: GraphQLNonNull(GraphQLInt) }, name: { type: GraphQLNonNull(GraphQLString) }, authorID: { type: GraphQLNonNull(GraphQLInt) }, author: { type: AuthorType, resolve: (book) => { return authors.find(author => author.id === book.authorID) } } }) })
const AuthorType = new GraphQLObjectType({ name: 'Author', description: 'This represents an author of book', fields: () => ({ id: { type: GraphQLNonNull(GraphQLInt) }, name: { type: GraphQLNonNull(GraphQLString) }, }) })
const RootQueryType = new GraphQLObjectType({ name: 'Query', description: 'Rooty Query', fields: () => ({ books: { type: new GraphQLList(BookType), description: 'List of All Books', resolve: () => books } }) })
const schema = new GraphQLSchema({ query: RootQueryType })
app.use('/graphql', expressGraphQL({ schema: schema, graphiql: true })) app.listen(5000., () => console.log('Server Running'))