Unpacking s3.ObjectSummary from bucket.objects.all() iteration

Question

I'm using boto3 to download files from s3, and i'm trying to unpack the values from bucket.objects.all() iteration:

bucket = boto3.Session(profile_name='default').resource('s3').Bucket(bucket_name)
for (bucket_name, key) in zip(bucket.objects.all()):
   print(bucket_name, key)

But this is returning the following error:

ValueError: not enough values to unpack (expected 2, got 1)

What I'm doing wrongly?

Answer 1

You can try this part instead of zip(bucket.objects.all()):

map(lambda x: (x.bucket_name, x.key), bucket.objects.all())

the function map allows to apply the function lambda (first parameter) to each members of the second parameter bucket.objects.all() which returns a list of ObjectSummary.

map returns a list you can loop

The lambda returns a tuple of 2 values so that you can unpack them.