Receiver pattern

Author: KyMidd

python/receiver.py

@@ -0,0 +1,60 @@
+import json
+import os
+import boto3
+
+# Initialize AWS Lambda client
+lambda_client = boto3.client('lambda')
+
+def lambda_handler(event, context):
+    """
+    Receives Slack events, performs basic validation, and asynchronously invokes the processor Lambda
+    """
+    print("Received event: %s", json.dumps(event))
+    
+    try:
+        # Parse the event body
+        body = json.loads(event['body'])
+        
+        # Handle Slack URL verification challenge
+        if 'challenge' in body:
+            return {
+                'statusCode': 200,
+                'body': json.dumps({'challenge': body['challenge']})
+            }
+            
+        # Get the event type
+        event_type = body.get('type', '')
+        
+        # Check for edited messages
+        if (
+            event_type == 'event_callback' and 
+            'edited' in body.get('event', {})
+        ):
+            print('Detected edited message, discarding')
+            return {
+                'statusCode': 200,
+                'body': json.dumps({'message': 'Edited message discarded'})
+            }
+        
+        # Only process events we care about
+        if event_type == 'event_callback':
+            # Asynchronously invoke the processor Lambda
+            lambda_client.invoke(
+                FunctionName=os.environ['PROCESSOR_FUNCTION_NAME'],
+                InvocationType='Event',  # Async invocation
+                Payload=json.dumps(event)
+            )
+            
+        # Always return 200 OK to Slack quickly
+        return {
+            'statusCode': 200,
+            'body': json.dumps({'message': 'Event received'})
+        }
+        
+    except Exception as e:
+        print("Error processing event: %s", str(e))
+        # Still return 200 to Slack to prevent retries
+        return {
+            'statusCode': 200,
+            'body': json.dumps({'message': 'Error processing event'})
+        }