sample of using "runtime.earlyReturn"

samples/conditional-pipeline/function1-rds.js

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+import { util, runtime } from '@aws-appsync/utils';
+import { select, createPgStatement } from '@aws-appsync/utils/rds';
+
+/**
+ * Sends a request to a Lambda function. Passes all information about the request from the `info` object.
+ * @param {import('@aws-appsync/utils').Context} ctx the context
+ */
+export function request(ctx) {
+	if (ctx.stash.useFirstDataSource === false) {
+		// if the condition is to not use first resolver, skip it
+		runtime.earlyReturn({});
+	}
+
+	return createPgStatement(select({ table: 'persons' }));
+}
+
+/**
+ * Process a Lambda function response
+ * @param {import('@aws-appsync/utils').Context} ctx the context
+ * @returns {*} the Lambda function response
+ */
+export function response(ctx) {
+	const { result, error } = ctx;
+	if (error) {
+		util.error(error.message, error.type, result);
+	}
+
+	ctx.stash.ds1resp = result;
+	return result;
+}

samples/conditional-pipeline/function2-lambda_async.js

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+import { util, runtime } from '@aws-appsync/utils';
+
+/**
+ * Sends a request to a Lambda function. Passes all information about the request from the `info` object.
+ * @param {import('@aws-appsync/utils').Context} ctx the context
+ */
+export function request(ctx) {
+	if (ctx.stash.useFirstDataSource === true) {
+		// If we already invoked the first resolver, skip this one
+		// Make sure to return result of previous function since we skip the current function
+		runtime.earlyReturn(ctx.prev.result);
+	}
+	return {
+		operation: 'Invoke',
+		invocationType: 'Event', // Invoke lambda async
+		payload: {
+			fieldName: ctx.info.fieldName,
+			parentTypeName: ctx.info.parentTypeName,
+			variables: ctx.info.variables,
+			selectionSetList: ctx.info.selectionSetList,
+			selectionSetGraphQL: ctx.info.selectionSetGraphQL,
+		},
+	};
+}
+
+/**
+ * Process a Lambda function response
+ * @param {import('@aws-appsync/utils').Context} ctx the context
+ * @returns {*} the Lambda function response
+ */
+export function response(ctx) {
+	const { result, error } = ctx;
+	if (error) {
+		util.error(error.message, error.type, result);
+	}
+
+	ctx.stash.ds2resp = result;
+
+	return result;
+}

samples/conditional-pipeline/index.js

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+/**
+ * Starts the resolver execution
+ * @param {import('@aws-appsync/utils').Context} ctx the context
+ * @returns {*} the return value sent to the first AppSync function
+ */
+export function request(ctx) {
+	// check the number of arguments and set a valude in the stash that we can conditionally use later
+	if (Object.keys(ctx.args).length > 5) {
+		ctx.stash.useFirstDataSource = true;
+	} else {
+		ctx.stash.useFirstDataSource = false;
+	}
+
+	return {};
+}
+
+/**
+ * Returns the resolver result
+ * @param {import('@aws-appsync/utils').Context} ctx the context
+ * @returns {*} the return value of the last AppSync function response handler
+ */
+export function response(ctx) {
+	return ctx.prev.result;
+}