GraphQL-demo 📊

The way you write the query is the way you get the data

A GraphQL demo for technological watch.

Install dependencies

yarn install

Start the server

yarn start

then go to http://localhost:4000/graphql

GraphQL logic items:

GraphQL schema

  type Address {
    street: String
    city: City
  }

  type User {
    id: ID
    name: String
    age: Int
    friends: [User]
    address: Address
  }

  type Query {
    users: [User]
    user(id: Int): User
  }

GraphQL resolver

const root = {
   user: ({id}) => {
      return users[id];
   },
   users: () => {
      return users;
   },
}

Get all the informations in one request with query:
You can now try your very first GraphQL query :

query{
  users {
    name
    age
  }
}

it allows to get all the users and their name & age.
To get all the users informations and their subsequent fields you can do so:

query{
  users {
    name
    age
    address {
      city {
        name
        code
        inhabitants
      }
      street
    }
  }
}

Let's assume now that you want the data of only one specific user with the the id 0

query{
  user(id: 0) {
    name
    age
    address {
      city {
        name
        code
        inhabitants
      }
      street
    }
  }
}

here you can see that the user resolver is different from the users one. They do a different job but still on the same API endpoint. This way, we could also get the cities with the corresponding resolver.

Post informations with mutation:

mutation{
  newUser(name: "Name", age: 45) {
    id
    name
    age
  }
}

It calls the resolver 'newUser', add the user to our list and then return this user to the specified format.

defless/GraphQL-demo

GraphQL-demo 📊

GraphQL logic items: