How do I get the size of a boto3 Collection?

Question

The way I have been using is to transform the Collection into a List and query the length:

s3 = boto3.resource(\'s3\')
bucket = s3.Bucket(\'my_bucket\')
size = l         


        

Answer 1

There is no way to get the count of keys in a bucket without listing all the objects this is a limitation of AWS S3 (see https://forums.aws.amazon.com/thread.jspa?messageID=164220).

Getting the Object Summaries (HEAD) doesn't get the actual data so should be a relatively inexpensive operation and if you are just discarding the list then you could do:

size = sum(1 for _ in bucket.objects.all())

Which will give you the number of objects without constructing a list.