Getting Started with GraphQL using Node.js/

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Root Fields and Resolvers

Root Fields and Resolvers

Learn how root fields and resolvers work in GraphQL.

We'll cover the following...

In this lesson, we’ll learn how a GraphQL query is executed by a GraphQL server that returns a response that reflects the structure of the invoked GraphQL query.

The sample query below is the same as the type system used throughout the lesson.

Javascript (babel-node)
    type Pizza {
      id: Int!
      pizza: String!
      stock: Int!
      toppings: [Topping!]!
    }
    type Topping {
      id: Int!
      topping: String!
    }
    type Query {
      pizzas: [Pizza]
    }

Let’s use one of our previous queries as an example.

Javascript (babel-node)
query{
  pizzas {
   __typename
    ... on Pizza {
      id
      toppings {
        id
        topping
      }
      pizza
    }
  }
}

We can conceptualize each field in a GraphQL query as a function. Each field is mapped to a resolver ...