fix(event-handler): allow event handler response to return array

[arnabrahman]

Summary

Previously, we couldn't return an array as an event handler response. This PR fixes that.

Changes

• update HandlerResponse type, replace JSONObject with JSONValue
• update error handling function to handle the new type
• Add unit tests to cover array response

Example:

import type { APIGatewayProxyEvent, Context } from 'aws-lambda';
import { DynamoDBClient } from '@aws-sdk/client-dynamodb';
import { ScanCommand, DynamoDBDocument } from '@aws-sdk/lib-dynamodb';
import { Router } from '@aws-lambda-powertools/event-handler/experimental-rest';

const ddbDocClient = DynamoDBDocument.from(new DynamoDBClient());
const app = new Router();

app.get('/orders', async () => {
  const response = await ddbDocClient.send(
    new ScanCommand({
      TableName: 'OrdersWorkshop',
    })
  );
  if (response.Items && response.Items.length > 0) {
    return response.Items;
  }
  return { message: 'No orders found' };
});

export const lambdaHandler = (
  event: APIGatewayProxyEvent,
  context: Context
) => {
  app.resolve(event, context);
};

Issue number: closes #4593

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[svozza]

Let's call this errorBodyToWebResponse.

[svozza]

Let's move this function to the event-handler/tests/unit/rest/helpers.ts file.

[svozza]

Two very minor comments but other than that, this is pretty much good to go.