extend SQS event handler

- report_batch_item_failures for partial batch processing
- maximum_concurrency to provide limits to SQS event source scaling
- remove outdated documentation about FIFO queues being unsupported

README.md

@@ -620,7 +620,7 @@ Optionally you can add [SNS message filters](http://docs.aws.amazon.com/sns/late
        ]
 ```
 
-[SQS](https://docs.aws.amazon.com/lambda/latest/dg/with-sqs.html) is also pulling messages from a stream.  At this time, [only "Standard" queues can trigger lambda events, not "FIFO" queues](https://docs.aws.amazon.com/lambda/latest/dg/with-sqs.html).  Read the AWS Documentation carefully since Lambda calls the SQS DeleteMessage API on your behalf once your function completes successfully.
+[SQS](https://docs.aws.amazon.com/lambda/latest/dg/with-sqs.html) is also pulling messages from a stream. Read the AWS Documentation carefully since Lambda calls the SQS DeleteMessage API on your behalf once your function completes successfully.
 
 ```javascript
        "events": [
@@ -629,6 +629,8 @@ Optionally you can add [SNS message filters](http://docs.aws.amazon.com/sns/late
                "event_source": {
                     "arn":  "arn:aws:sqs:us-east-1:12341234:your-queue-name-arn",
                     "batch_size": 10, // Max: 10. Use 1 to trigger immediate processing
+                    "report_batch_item_failures": false, // whether the handler returns a `batchItemFailures` field
+                    "maximum_concurrency": 0, // maximum number of parallel lambda instances for this event source.
                     "enabled": true // Default is false
                }
            }

zappa/utilities.py

@@ -277,6 +277,23 @@ def __init__(self, context, config):
         def batch_window(self):
             return self._config.get("batch_window", 1 if self.batch_size > 10 else 0)
 
+        @property
+        def function_response_types(self):
+            return (
+                ["ReportBatchItemFailures"]
+                if self._config.get("report_batch_item_failures", False)
+                else []
+            )
+
+        @property
+        def scaling_config(self):
+            maximum_concurrency = self._config.get("maximum_concurrency", None)
+
+            if maximum_concurrency is None:
+                return {}
+
+            return {"MaximumConcurrency": maximum_concurrency}
+
         def _get_uuid(self, function):
             uuid = None
             response = self._lambda.call(
@@ -297,6 +314,8 @@ def add(self, function):
                     EventSourceArn=self.arn,
                     BatchSize=self.batch_size,
                     MaximumBatchingWindowInSeconds=self.batch_window,
+                    FunctionResponseTypes=self.function_response_types,
+                    ScalingConfig=self.scaling_config,
                     Enabled=self.enabled,
                 )
                 LOG.debug(response)