Checks are failing. Will not request review until checks are succeeding. If you'd like to override that behavior, comment assign set of reviewers

Assigning reviewers. If you would like to opt out of this review, comment assign to next reviewer:

R: @shunping for label python.

Available commands:

• stop reviewer notifications - opt out of the automated review tooling
• remind me after tests pass - tag the comment author after tests pass
• waiting on author - shift the attention set back to the author (any comment or push by the author will return the attention set to the reviewers)

The PR bot will only process comments in the main thread (not review comments).

I ran some tests on both apis, it does have some difference, though not big

from google.cloud import storage
import timeit

storage_client = storage.Client()

bucket = storage_client.bucket("shunping-test")

time_taken = timeit.timeit(
  lambda : bucket.get_blob("wordcount-output-00000-of-00001"),
  number=100)
print(time_taken)

blob = bucket.blob("wordcount-output-00000-of-00001")
time_taken = timeit.timeit(blob.exists, number=100)

print(time_taken)

6.079686500015669
5.889628666976932

Thanks for attempting to fix the issue.

I see you are trying to replace bucket.get_blob, called in _gcs_object, with blob.exists.

I took a look at the two function calls.

• bucket.get_blob

  • calling blob.reload inherited from _PropertyMixin at https://github.com/googleapis/python-storage/blob/v2.18.2/google/cloud/storage/_helpers.py#L216

    • calling client._get_resource at https://github.com/googleapis/python-storage/blob/v2.18.2/google/cloud/storage/_helpers.py#L300

• blob.exists

  • calling client._get_resource at https://github.com/googleapis/python-storage/blob/v2.18.2/google/cloud/storage/blob.py#L734

It seems that under the hood, both apis are calling the same client._get_resource, though the query parameters may be different. I am not sure if the change could make any performance improvement for the use case here.

Adding @cojenco and @andrewsg from GCS client library to chime in regarding any performance difference between bucket.get_blob and blob.exists.

Thanks for tagging! That's right, both bucket.get_blob and blob.exists ultimately call client._get_resource, so the performance difference is likely negligible.