I ran into a little issue today parsing a S3 SQS event that was sent to Lambda via a SQS trigger.  I assumed the incoming event to Lambda was 100% of type dict.  Given this, I assumed I could pull the bucket name and key using this syntax.

bucketname = event['Records'][0]['body']['Records'][0]['s3']['bucket']['name']
objectname = event['Records'][0]['body']['Records'][0]['s3']['object']['key']

As it turns out the incoming event is not 100% of type dict and I got the following error.  

string indices must be integers

The Records after the body ([‘Records’][0][‘body’]) are of type str.  Below is the updated code to pull the bucket name and key from the incoming event.

event_body_records_string = event['Records'][0]['body']
event_body_records_dict = json.loads(event_body_records_string)

bucketname = event_body_records_dict['Records'][0]['s3']['bucaket']['name']
objectname = event_body_records_dict['Records'][0]['s3']['object']['key']

Now everything works out great!!!

When using the “receive_message” Python Boto function to pull message(s) from a SQS queue, you will always get a response back when the command completes.  However, how do you determine if the response you got back actually contains a valid message?

Quick trick:

response = sqs.receive_message

if 'Messages' in response:
    print("Message on the queue to process")

else:
    print("No messages on the queue to process")

Thats about it!!