Sample graphql api app and static json data for testing

To setup a project install nodejs and vscode for IDE and in a folder run below commands.

npm init --yes

npm i --save express express-graphql graphql lodash

Schema code to link with graphql queries.

schema/schema.js

--

const graphql = require('graphql');
const _ = require('lodash');
const {
 GraphQLObjectType,
 GraphQLString,
 GraphQLInt,
 GraphQLSchema
} = graphql;

//static data for testing
const users = [
  {id:'23',firstName: 'Bill', age:20},
  {id:'47',firstName: 'Samantha', age:21},
];

const UserType = new GraphQLObjectType({
 name: 'User',
 fields:{
   id: {type: GraphQLString},
   firstName: {type: GraphQLString},
   age: {type: GraphQLInt}
 }
});

const RootQuery = new GraphQLObjectType({
 name: 'RootQueryType',
 fields: {
  user: {
   type: UserType,
   args: {id: { type: GraphQLString}},
   resolve(parentValue,args){
    return _.find(users, {id: args.id});
   }
  }
 }
});

module.exports = new GraphQLSchema({
 query: RootQuery
});

To host this we have this express app running.

server.js

--

const express = require('express');
const expressGraphQL = require('express-graphql');
const schema = require('./schema/schema');

const app = express();


app.use('/graphql',expressGraphQL({
 schema, //es6 equavalant to schema: schema
 graphiql: true
}));

app.listen(4000,()=>{
 console.log('Listening');
});

To run the app: node server.js

Inside a web browser, launch : localhost:4000/graphql?query=
It will open inside the GraphiQL UI. There you run this sample query:

{
 user(id: "23"){
   id,
   firstName,
   age
 }
}

docs link right side, will give document explorer of the data.