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Node Interface

The Node interface is a convention first introduced by Relay, the GraphQL client that is used and developed by Facebook. It ensures that all objects have a unique identifier across the application and that they can be refetched individually via a standardized field on the root query type.

Slicknode also uses the Node interface to determine which types should be persisted to the database. When a type implements the Node interface, Slicknode by default automatically creates the corresponding database table for the type and the fields.

Definition

The Node interface has the following definition:

interface Node {
    id: ID!
}

Description

The Node interface only has one field id of type ID!. The id of the Node is globally unique, there cannot be two nodes with the same ID in your GraphQL API.

Usage

To enable the storage for a type, it needs to implement the Node interface.

type Blog_Article implements Node {
    id: ID!
    title: String
}

This would create a type Blog_Article that is persisted to the database along with the fields for the CRUD API.

Querying

All objects of types that implement the Node interface can be refetched via the node field on the root query type:

query {
    node(id: "theglobalnodeid") {
        id

        # Use fragments of the loaded type to load specific fields
        ...on Blog_Article {
            title
        }
    }
}

This can be used to refresh any persisted object in the UI.