fix(parser): parse sqs record body field as JSON and S3Schema in S3SqsEventNoificationRecordSchema (#3529)

Co-authored-by: Andrea Amorosi <dreamorosi@gmail.com>

Author: cyrildewit

packages/parser/src/schemas/s3.ts

@@ -1,4 +1,5 @@
 import { z } from 'zod';
+import { JSONStringified } from '../helpers.js';
 import { EventBridgeSchema } from './eventbridge.js';
 import { SqsRecordSchema } from './sqs.js';
 
@@ -170,12 +171,15 @@ const S3Schema = z.object({
 });
 
 const S3SqsEventNotificationRecordSchema = SqsRecordSchema.extend({
-  body: z.string(),
+  body: JSONStringified(S3Schema),
 });
 
 /**
  * Zod schema for S3 -> SQS -> Lambda event notification.
  *
+ * Each SQS record’s body field is automatically parsed from a JSON string
+ * and then validated as an S3 event.
+ *
  * @example
  * ```json
  * {

packages/parser/tests/unit/schema/s3.test.ts

@@ -196,11 +196,15 @@ describe('Schema: S3', () => {
       filename: 'sqs-event',
     });
 
+    const expected = structuredClone(event);
+    // @ts-expect-error - Modifying the expected result to account for transform
+    expected.Records[0].body = JSON.parse(expected.Records[0].body);
+
     // Prepare
     const result = S3SqsEventNotificationSchema.parse(event);
 
     // Assess
-    expect(result).toStrictEqual(event);
+    expect(result).toStrictEqual(expected);
   });
 
   it('throws if the S3 event notification SQS event is not valid', () => {