combine async and sync processing functions in one class

Author: Alexander Melnyk

docs/snippets/batch/accessProcessedMessages.ts

@@ -25,7 +25,7 @@ export const handler = async (
   const batch = event.Records; // (1)!
 
   processor.register(batch, recordHandler, { context }); // (2)!
-  const processedMessages = processor.process();
+  const processedMessages = await processor.process();
 
   for (const message of processedMessages) {
     const status: 'success' | 'fail' = message[0];

docs/snippets/batch/advancedTracingRecordHandler.ts

@@ -1,7 +1,7 @@
 import {
   BatchProcessor,
   EventType,
-  processPartialResponse,
+  processPartialResponseSync,
 } from '@aws-lambda-powertools/batch';
 import { Tracer, captureLambdaHandler } from '@aws-lambda-powertools/tracer';
 import middy from '@middy/core';
@@ -36,7 +36,7 @@ const recordHandler = (record: SQSRecord): void => {
 
 export const handler = middy(
   async (event: SQSEvent, context: Context): Promise<SQSBatchResponse> => {
-    return processPartialResponse(event, recordHandler, processor, {
+    return processPartialResponseSync(event, recordHandler, processor, {
       context,
     });
   }

docs/snippets/batch/customPartialProcessor.ts

@@ -7,7 +7,7 @@ import { marshall } from '@aws-sdk/util-dynamodb';
 import {
   EventType,
   BasePartialBatchProcessor,
-  processPartialResponse,
+  processPartialResponseSync,
 } from '@aws-lambda-powertools/batch';
 import type {
   SuccessResponse,
@@ -27,12 +27,6 @@ class MyPartialProcessor extends BasePartialBatchProcessor {
     this.#tableName = tableName;
   }
 
-  public async asyncProcessRecord(
-    _record: BaseRecord
-  ): Promise<SuccessResponse | FailureResponse> {
-    throw new Error('Not implemented');
-  }
-
   /**
    * It's called once, **after** processing the batch.
    *
@@ -64,13 +58,21 @@ class MyPartialProcessor extends BasePartialBatchProcessor {
     this.successMessages = [];
   }
 
+  public async processRecord(
+    _record: BaseRecord
+  ): Promise<SuccessResponse | FailureResponse> {
+    throw new Error('Not implemented');
+  }
+
   /**
    * It handles how your record is processed.
    *
    * Here we are keeping the status of each run, `this.handler` is
    * the function that is passed when calling `processor.register()`.
    */
-  public processRecord(record: BaseRecord): SuccessResponse | FailureResponse {
+  public processRecordSync(
+    record: BaseRecord
+  ): SuccessResponse | FailureResponse {
     try {
       const result = this.handler(record);
 
@@ -91,7 +93,7 @@ export const handler = async (
   event: SQSEvent,
   context: Context
 ): Promise<SQSBatchResponse> => {
-  return processPartialResponse(event, recordHandler, processor, {
+  return processPartialResponseSync(event, recordHandler, processor, {
     context,
   });
 };

docs/snippets/batch/extendingFailure.ts

@@ -4,7 +4,7 @@ import {
   EventType,
   FailureResponse,
   EventSourceType,
-  processPartialResponse,
+  processPartialResponseSync,
 } from '@aws-lambda-powertools/batch';
 import { Logger } from '@aws-lambda-powertools/logger';
 import type {
@@ -47,7 +47,7 @@ export const handler = async (
   event: SQSEvent,
   context: Context
 ): Promise<SQSBatchResponse> => {
-  return processPartialResponse(event, recordHandler, processor, {
+  return processPartialResponseSync(event, recordHandler, processor, {
     context,
   });
 };

docs/snippets/batch/gettingStartedAsync.ts

@@ -1,7 +1,7 @@
 import {
-  AsyncBatchProcessor,
+  BatchProcessor,
   EventType,
-  asyncProcessPartialResponse,
+  processPartialResponse,
 } from '@aws-lambda-powertools/batch';
 import axios from 'axios'; // axios is an external dependency
 import type {
@@ -11,7 +11,7 @@ import type {
   SQSBatchResponse,
 } from 'aws-lambda';
 
-const processor = new AsyncBatchProcessor(EventType.SQS);
+const processor = new BatchProcessor(EventType.SQS);
 
 const recordHandler = async (record: SQSRecord): Promise<number> => {
   const res = await axios.post('https://httpbin.org/anything', {
@@ -25,7 +25,7 @@ export const handler = async (
   event: SQSEvent,
   context: Context
 ): Promise<SQSBatchResponse> => {
-  return await asyncProcessPartialResponse(event, recordHandler, processor, {
+  return await processPartialResponse(event, recordHandler, processor, {
     context,
   });
 };

docs/snippets/batch/gettingStartedDynamoDBStreams.ts

@@ -1,7 +1,7 @@
 import {
   BatchProcessor,
   EventType,
-  processPartialResponse,
+  processPartialResponseSync,
 } from '@aws-lambda-powertools/batch';
 import { Logger } from '@aws-lambda-powertools/logger';
 import type {
@@ -29,7 +29,7 @@ export const handler = async (
   event: DynamoDBStreamEvent,
   context: Context
 ): Promise<DynamoDBBatchResponse> => {
-  return processPartialResponse(event, recordHandler, processor, {
+  return processPartialResponseSync(event, recordHandler, processor, {
     context,
   });
 };

docs/snippets/batch/gettingStartedErrorHandling.ts

@@ -1,7 +1,7 @@
 import {
   BatchProcessor,
   EventType,
-  processPartialResponse,
+  processPartialResponseSync,
 } from '@aws-lambda-powertools/batch';
 import { Logger } from '@aws-lambda-powertools/logger';
 import type {
@@ -37,7 +37,7 @@ export const handler = async (
   context: Context
 ): Promise<SQSBatchResponse> => {
   // prettier-ignore
-  return processPartialResponse(event, recordHandler, processor, { // (2)!
+  return processPartialResponseSync(event, recordHandler, processor, { // (2)!
     context,
   });
 };

docs/snippets/batch/gettingStartedKinesis.ts

@@ -1,7 +1,7 @@
 import {
   BatchProcessor,
   EventType,
-  processPartialResponse,
+  processPartialResponseSync,
 } from '@aws-lambda-powertools/batch';
 import { Logger } from '@aws-lambda-powertools/logger';
 import type {
@@ -24,7 +24,7 @@ export const handler = async (
   event: KinesisStreamEvent,
   context: Context
 ): Promise<KinesisStreamBatchResponse> => {
-  return processPartialResponse(event, recordHandler, processor, {
+  return processPartialResponseSync(event, recordHandler, processor, {
     context,
   });
 };

docs/snippets/batch/gettingStartedSQS.ts

@@ -1,7 +1,7 @@
 import {
   BatchProcessor,
   EventType,
-  processPartialResponse,
+  processPartialResponseSync,
 } from '@aws-lambda-powertools/batch';
 import { Logger } from '@aws-lambda-powertools/logger';
 import type {
@@ -28,7 +28,7 @@ export const handler = async (
   context: Context
 ): Promise<SQSBatchResponse> => {
   // prettier-ignore
-  return processPartialResponse(event, recordHandler, processor, { // (3)!
+  return processPartialResponseSync(event, recordHandler, processor, { // (3)!
     context,
   });
 };

docs/snippets/batch/gettingStartedSQSFifo.ts

@@ -1,6 +1,6 @@
 import {
   SqsFifoPartialProcessor,
-  processPartialResponse,
+  processPartialResponseSync,
 } from '@aws-lambda-powertools/batch';
 import { Logger } from '@aws-lambda-powertools/logger';
 import type {
@@ -25,7 +25,7 @@ export const handler = async (
   event: SQSEvent,
   context: Context
 ): Promise<SQSBatchResponse> => {
-  return processPartialResponse(event, recordHandler, processor, {
+  return processPartialResponseSync(event, recordHandler, processor, {
     context,
   });
 };

docs/utilities/batch.md

@@ -13,23 +13,23 @@ stateDiagram-v2
     direction LR
     BatchSource: Amazon SQS <br/><br/> Amazon Kinesis Data Streams <br/><br/> Amazon DynamoDB Streams <br/><br/>
     LambdaInit: Lambda invocation
-    BatchProcessor: Batch Processor
+    BatchProcessorSync: Batch Processor
     RecordHandler: Record Handler function
     YourLogic: Your logic to process each batch item
     LambdaResponse: Lambda response
 
     BatchSource --> LambdaInit
 
-    LambdaInit --> BatchProcessor
-    BatchProcessor --> RecordHandler
+    LambdaInit --> BatchProcessorSync
+    BatchProcessorSync --> RecordHandler
 
-    state BatchProcessor {
+    state BatchProcessorSync {
         [*] --> RecordHandler: Your function
         RecordHandler --> YourLogic
     }
 
-    RecordHandler --> BatchProcessor: Collect results
-    BatchProcessor --> LambdaResponse: Report items that failed processing
+    RecordHandler --> BatchProcessorSync: Collect results
+    BatchProcessorSync --> LambdaResponse: Report items that failed processing
 ```
 
 ## Key features
@@ -99,9 +99,9 @@ The remaining sections of the documentation will rely on these samples. For comp
 
 Processing batches from SQS works in three stages:
 
-1. Instantiate **`BatchProcessor`** and choose **`EventType.SQS`** for the event type
+1. Instantiate **`BatchProcessorSync`** and choose **`EventType.SQS`** for the event type
 2. Define your function to handle each batch record, and use the `SQSRecord` type annotation for autocompletion
-3. Use **`processPartialResponse`** to kick off processing
+3. Use **`processPartialResponseSync`** to kick off processing
 
 ???+ info
     This code example optionally uses Logger for completion.
@@ -149,9 +149,9 @@ This helps preserve the ordering of messages in your queue.
 
 Processing batches from Kinesis works in three stages:
 
-1. Instantiate **`BatchProcessor`** and choose **`EventType.KinesisDataStreams`** for the event type
+1. Instantiate **`BatchProcessorSync`** and choose **`EventType.KinesisDataStreams`** for the event type
 2. Define your function to handle each batch record, and use the `KinesisStreamRecord` type annotation for autocompletion
-3. Use **`processPartialResponse`** to kick off processing
+3. Use **`processPartialResponseSync`** to kick off processing
 
 ???+ info
     This code example optionally uses Logger for completion.
@@ -182,9 +182,9 @@ Processing batches from Kinesis works in three stages:
 
 Processing batches from DynamoDB Streams works in three stages:
 
-1. Instantiate **`BatchProcessor`** and choose **`EventType.DynamoDBStreams`** for the event type
+1. Instantiate **`BatchProcessorSync`** and choose **`EventType.DynamoDBStreams`** for the event type
 2. Define your function to handle each batch record, and use the `DynamoDBRecord` type annotation for autocompletion
-3. Use **`processPartialResponse`** to kick off processing
+3. Use **`processPartialResponseSync`** to kick off processing
 
 ???+ info
     This code example optionally uses Logger for completion.
@@ -225,7 +225,7 @@ By default, we catch any exception raised by your record handler function. This
     --8<--
     ```
 
-    1. Any exception works here. See [extending BatchProcessor section, if you want to override this behavior.](#extending-batchprocessor)
+    1. Any exception works here. See [extending BatchProcessorSync section, if you want to override this behavior.](#extending-batchprocessor)
 
     2. Exceptions raised in `record_handler` will propagate to `process_partial_response`. <br/><br/> We catch them and include each failed batch item identifier in the response dictionary (see `Sample response` tab).
 
@@ -249,7 +249,7 @@ The following sequence diagrams explain how each Batch processor behaves under d
 
 > Read more about [Batch Failure Reporting feature in AWS Lambda](https://docs.aws.amazon.com/lambda/latest/dg/with-sqs.html#services-sqs-batchfailurereporting){target="_blank"}.
 
-Sequence diagram to explain how [`BatchProcessor` works](#processing-messages-from-sqs) with SQS Standard queues.
+Sequence diagram to explain how [`BatchProcessorSync` works](#processing-messages-from-sqs) with SQS Standard queues.
 
 <center>
 ```mermaid
@@ -302,7 +302,7 @@ sequenceDiagram
 
 > Read more about [Batch Failure Reporting feature](https://docs.aws.amazon.com/lambda/latest/dg/with-kinesis.html#services-kinesis-batchfailurereporting){target="_blank"}.
 
-Sequence diagram to explain how `BatchProcessor` works with both [Kinesis Data Streams](#processing-messages-from-kinesis) and [DynamoDB Streams](#processing-messages-from-dynamodb).
+Sequence diagram to explain how `BatchProcessorSync` works with both [Kinesis Data Streams](#processing-messages-from-kinesis) and [DynamoDB Streams](#processing-messages-from-dynamodb).
 
 For brevity, we will use `Streams` to refer to either services. For theory on stream checkpoints, see this [blog post](https://aws.amazon.com/blogs/compute/optimizing-batch-processing-with-custom-checkpoints-in-aws-lambda/){target="_blank"}
 
@@ -358,7 +358,7 @@ sequenceDiagram
 
 ### Processing messages asynchronously
 
-You can use `AsyncBatchProcessor` class and `asyncProcessPartialResponse` function to process messages concurrently.
+You can use `BatchProcessor` class and `asyncProcessPartialResponse` function to process messages concurrently.
 
 ???+ question "When is this useful?"
     Your use case might be able to process multiple records at the same time without conflicting with one another.
@@ -367,15 +367,15 @@ You can use `AsyncBatchProcessor` class and `asyncProcessPartialResponse` functi
 
     The reason this is not the default behaviour is that not all use cases can handle concurrency safely (e.g., loyalty points must be updated in order).
 
-```typescript hl_lines="1-5 14 28-30" title="High-concurrency with AsyncBatchProcessor"
+```typescript hl_lines="1-5 14 28-30" title="High-concurrency with BatchProcessor"
 --8<-- "docs/snippets/batch/gettingStartedAsync.ts"
 ```
 
 ## Advanced
 
 ### Accessing processed messages
 
-Use the `BatchProcessor` directly in your function to access a list of all returned values from your `recordHandler` function.
+Use the `BatchProcessorSync` directly in your function to access a list of all returned values from your `recordHandler` function.
 
 * **When successful**. We will include a tuple with `success`, the result of `recordHandler`, and the batch record
 * **When failed**. We will include a tuple with `fail`, exception as a string, and the batch record
@@ -384,32 +384,32 @@ Use the `BatchProcessor` directly in your function to access a list of all retur
 --8<-- "docs/snippets/batch/accessProcessedMessages.ts"
 ```
 
-1.  The processor requires the records array. This is typically handled by `processPartialResponse`.
+1.  The processor requires the records array. This is typically handled by `processPartialResponseSync`.
 2.  You need to register the `batch`, the `recordHandler` function, and optionally the `context` to access the Lambda context.
 
 ### Accessing Lambda Context
 
 Within your `recordHandler` function, you might need access to the Lambda context to determine how much time you have left before your function times out.
 
-We can automatically inject the [Lambda context](https://docs.aws.amazon.com/lambda/latest/dg/typescript-context.html){target="_blank"} into your `recordHandler` as optional second argument if you register it when using `BatchProcessor` or the `processPartialResponse` function.
+We can automatically inject the [Lambda context](https://docs.aws.amazon.com/lambda/latest/dg/typescript-context.html){target="_blank"} into your `recordHandler` as optional second argument if you register it when using `BatchProcessorSync` or the `processPartialResponseSync` function.
 
 ```typescript hl_lines="17 35"
 --8<-- "docs/snippets/batch/accessLambdaContext.ts"
 ```
 
-### Extending BatchProcessor
+### Extending BatchProcessorSync
 
-You might want to bring custom logic to the existing `BatchProcessor` to slightly override how we handle successes and failures.
+You might want to bring custom logic to the existing `BatchProcessorSync` to slightly override how we handle successes and failures.
 
-For these scenarios, you can subclass `BatchProcessor` and quickly override `successHandler` and `failureHandler` methods:
+For these scenarios, you can subclass `BatchProcessorSync` and quickly override `successHandler` and `failureHandler` methods:
 
 * **`successHandler()`** – Keeps track of successful batch records
 * **`failureHandler()`** – Keeps track of failed batch records
 
 ???+ example
 	Let's suppose you'd like to add a metric named `BatchRecordFailures` for each batch record that failed processing
 
-```typescript hl_lines="17 21 25 31 35" title="Extending failure handling mechanism in BatchProcessor"
+```typescript hl_lines="17 21 25 31 35" title="Extending failure handling mechanism in BatchProcessorSync"
 --8<-- "docs/snippets/batch/extendingFailure.ts"
 ```
 
@@ -446,7 +446,7 @@ classDiagram
 * **`clean()`** – teardown logic called once after `processRecord` completes
 * **`asyncProcessRecord()`** – If you need to implement asynchronous logic, use this method, otherwise define it in your class with empty logic
 
-You can then use this class as a context manager, or pass it to `processPartialResponse` to process the records in your Lambda handler function.
+You can then use this class as a context manager, or pass it to `processPartialResponseSync` to process the records in your Lambda handler function.
 
 ```typescript hl_lines="21 30 41 62 73 84" title="Creating a custom batch processor"
 --8<-- "docs/snippets/batch/customPartialProcessor.ts"
@@ -466,7 +466,7 @@ You can use Tracer to create subsegments for each batch record processed. To do
 
 ## Testing your code
 
-As there is no external calls, you can unit test your code with `BatchProcessor` quite easily.
+As there is no external calls, you can unit test your code with `BatchProcessorSync` quite easily.
 
 **Example**: