doc: async sqs fifo message processing

Author: arnabrahman

docs/utilities/batch.md

@@ -149,21 +149,27 @@ Enable the `skipGroupOnError` option for seamless processing of messages from va
 
 === "Recommended"
 
-    ```typescript hl_lines="1-4 8"
+    ```typescript hl_lines="1-4 8 20"
     --8<-- "examples/snippets/batch/gettingStartedSQSFifo.ts"
     ```
 
     1. **Step 1**. Creates a partial failure batch processor for SQS FIFO queues. See [partial failure mechanics for details](#partial-failure-mechanics)
 
+=== "Async processing"
+
+    ```typescript hl_lines="1-4 8 20"
+    --8<-- "examples/snippets/batch/gettingStartedSQSFifoAsync.ts"
+    ```
+
 === "Enabling skipGroupOnError flag"
 
     ```typescript hl_lines="1-4 13 30"
     --8<-- "examples/snippets/batch/gettingStartedSQSFifoSkipGroupOnError.ts"
     ```
 
 !!! Note
-    Note that SqsFifoPartialProcessor is synchronous using `processPartialResponseSync`.
-    This is because we need to preserve the order of messages in the queue. See [Async or sync processing section](#async-or-sync-processing) for more details.
+    Note that `SqsFifoPartialProcessor` is synchronous using `processPartialResponseSync`.
+    If you need asynchronous processing while preserving the order of messages in the queue, use `SqsFifoPartialProcessorAsync` with `processPartialResponse`.
 
 ### Processing messages from Kinesis
 

examples/snippets/batch/gettingStartedSQSFifoAsync.ts

@@ -0,0 +1,22 @@
+import {
+  SqsFifoPartialProcessorAsync,
+  processPartialResponse,
+} from '@aws-lambda-powertools/batch';
+import { Logger } from '@aws-lambda-powertools/logger';
+import type { SQSHandler, SQSRecord } from 'aws-lambda';
+
+const processor = new SqsFifoPartialProcessorAsync();
+const logger = new Logger();
+
+const recordHandler = async (record: SQSRecord): Promise<void> => {
+  const payload = record.body;
+  if (payload) {
+    const item = JSON.parse(payload);
+    logger.info('Processed item', { item });
+  }
+};
+
+export const handler: SQSHandler = async (event, context) =>
+  processPartialResponse(event, recordHandler, processor, {
+    context,
+  });