Boto3 S3 sort bucket by last modified

Question

I need to fetch a list of items from S3 using Boto3, but instead of returning default sort order (descending) I want it to return it via reverse order.

I know you can do it via awscli:

aws s3api list-objects --bucket mybucketfoo --query "reverse(sort_by(Contents,&LastModified))"

and its doable via the UI console (not sure if this is done client side or server side)

I cant seem to see how to do this in Boto3.

I am currently fetching all the files, and then sorting...but that seems overkill, especially if I only care about the 10 or so most recent files.

The filter system seems to only accept the Prefix for s3, nothing else. How do I solve this issue?

Answer 1

I tried the following method. Its not 100% optimum, but it gets the job done with the limitations boto3 has as of this time.

s3 = boto3.resource('s3')
my_bucket = s3.Bucket('myBucket')
unsorted = []
for file in my_bucket.objects.filter():
   unsorted.append(file)

files = [obj.key for obj in sorted(unsorted, key=get_last_modified, 
    reverse=True)][0:9]

Comments

Getting error for 'get_last_modified'

NameError: name 'get_last_modified' is not defined

 how we have to define this.

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Hi, @Aryani,

Are you using Python 2.7 or Python 3?