Load resolvers

Up until now, we have not interacted with AppSync Butler. We have

1. Defined a GraphQL schema.
2. Setup the resolvers.
3. Instantialized the AppSync API construct.

The AppSync construct is not yet aware of the on-disk resolvers. AppSync Butler handles this process seamlessly. To conveniently retrieve a CDK or SST Loader instance, we can utilize the createLoader function.

Serverless Stack Toolkit

stacks/MyStack.ts

import * as sst from "@serverless-stack/resources";
import { createLoader } from 'aws-appsync-butler';

export default class MyStack extends sst.Stack {
  constructor(scope: sst.App, id: string, props: sst.StackProps) {
    super(scope, id, props);

    const api = new sst.AppSyncApi(this, "api", {
      graphqlApi: { schema: "graphql/index.graphql" }
    });

    const loader = createLoader(this, { api });
    loader.load();
  }
}

AWS Cloud Development Kit

lib/app-stack.ts

import { Stack, StackProps } from 'aws-cdk-lib';
import { Construct } from 'constructs';
import { GraphqlApi } from '@aws-cdk/aws-appsync';
import { createLoader } from 'aws-appsync-butler';

export class AppStack extends Stack {
  constructor(scope: Construct, id: string, props?: StackProps) {
    super(scope, id, props);

    const api = new GraphqlApi(this, "api", {
      name: "time-pingpong-api"
    });

    const loader = createLoader(this, { api });
    loader.load();
  }
}

tip

Instead of explicitly associating resolvers with data sources in request mapping templates, you can specify a default data source when creating the loader.

const loader = createLoader(this, { api, defaultUnitResolverDataSource: 'none' });

For other options that you may pass, check LoaderOptions.