feat(experimental): add bidi stream retry manager. (#1632)

- Add bidi stream retry manager. It will the main class that would be
responsible for retries.
- Integrate MRD with bidi stream retry manager and reads resumption
strategy
- Added conformance tests for all error scenarios and smart resumption
for bidi reads
- Refactored MRD's `download_ranges()` method, which will now use retry
manager's `execute()` method to send the requests
- Modified the logic to parse and handle the
`BidiReadObjectRedirectedError`.
- Modified cloud build configuration to also pull the latest changes of
the current PR.
- Formatted few more files using black formatter

Author: Pulkit0110

cloudbuild/run_zonal_tests.sh

@@ -6,6 +6,7 @@ sudo apt-get update && sudo apt-get install -y git python3-pip python3-venv
 # Clone the repository and checkout the specific commit from the build trigger.
 git clone https://github.com/googleapis/python-storage.git
 cd python-storage
+git fetch origin "refs/pull/${_PR_NUMBER}/head"
 git checkout ${COMMIT_SHA}
 
 

cloudbuild/zb-system-tests-cloudbuild.yaml

@@ -68,7 +68,7 @@ steps:
         # Execute the script on the VM via SSH.
         # Capture the exit code to ensure cleanup happens before the build fails.
         set +e
-        gcloud compute ssh ${_VM_NAME} --zone=${_ZONE} --internal-ip --ssh-key-file=/workspace/.ssh/google_compute_engine --command="ulimit -n {_ULIMIT}; COMMIT_SHA=${COMMIT_SHA} _ZONAL_BUCKET=${_ZONAL_BUCKET} bash run_zonal_tests.sh"
+        gcloud compute ssh ${_VM_NAME} --zone=${_ZONE} --internal-ip --ssh-key-file=/workspace/.ssh/google_compute_engine --command="ulimit -n {_ULIMIT}; COMMIT_SHA=${COMMIT_SHA} _ZONAL_BUCKET=${_ZONAL_BUCKET} _PR_NUMBER=${_PR_NUMBER} bash run_zonal_tests.sh"
         EXIT_CODE=$?
         set -e
 

google/cloud/storage/_experimental/asyncio/_utils.py

@@ -16,6 +16,7 @@
 
 from google.api_core import exceptions
 
+
 def raise_if_no_fast_crc32c():
     """Check if the C-accelerated version of google-crc32c is available.
 
@@ -24,7 +25,7 @@ def raise_if_no_fast_crc32c():
     raises google.api_core.exceptions.FailedPrecondition: If the C extension is not available.
     returns: True if the C extension is available.
     rtype: bool
-    
+
     """
     if google_crc32c.implementation != "c":
         raise exceptions.FailedPrecondition(