Feat(storage): add sample for list buckets partial success

[thiyaguk09]

This PR adds a new code sample and system test demonstrating how to handle Partial Success when listing Cloud Storage buckets.

The returnPartialSuccess feature is critical for building resilient applications. It allows the buckets() method to return successfully even if specific regions are experiencing downtime, providing a list of reachable buckets along with a list of unreachable resource paths.

Changes

• New Sample: Added storage_list_buckets_partial_success snippet.
• Logic: Implemented handling for the unreachable() method in BucketIterator.
• Testing: Added a system test to verify the snippet executes correctly and successfully communicates with the Storage API.

---

Implementation Notes

• Assertion Strategy: I have included assertTrue(true) at the end of the system test. This serves as a "completion assertion" to explicitly confirm that the entire snippet executed and returned without throwing an exception, which is particularly useful in system tests where the network is involved.
• Unreachable Buckets: This is a system test hitting the live API. Under normal conditions, all Google Cloud regions are healthy, meaning the unreachable() array will be empty. Therefore, we do not assert specific "Unreachable" output strings to avoid false negatives. The test instead focuses on verifying the reachable Bucket: output, proving the API connection and the returnPartialSuccess configuration are working correctly.

[snippet-bot]

Here is the summary of changes.

You are about to add 1 region tag.

• storage/src/list_buckets_partial_success.php:26, tag storage_list_buckets_partial_success

---

This comment is generated by snippet-bot.
If you find problems with this result, please file an issue at:
https://github.com/googleapis/repo-automation-bots/issues.
To update this comment, add snippet-bot:force-run label or use the checkbox below:

• Refresh this comment

[gemini-code-assist]

Summary of Changes

Hello @thiyaguk09, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a new feature that enhances the resilience of applications interacting with Google Cloud Storage. It provides a mechanism to handle scenarios where some regions might be experiencing downtime while listing buckets, ensuring that the application can still retrieve available bucket information and identify unreachable resources, rather than failing entirely.

Highlights

• New Code Sample: A new PHP code sample, storage_list_buckets_partial_success, has been added to demonstrate how to list Cloud Storage buckets while gracefully handling partial failures due to regional downtime.
• Partial Success Logic: The sample utilizes the returnPartialSuccess option with StorageClient::buckets() and includes logic to check for and print unreachable resource paths using the unreachable() method of the BucketIterator.
• System Test Coverage: A new system test, testListBucketsPartialSuccess, has been introduced to verify the correct execution of the new sample, ensuring it communicates successfully with the Storage API and handles partial success as expected.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[gemini-code-assist]

Code Review

This pull request introduces a new code sample and a corresponding system test to demonstrate the 'returnPartialSuccess' feature when listing Cloud Storage buckets. The implementation is clear and effectively shows how to handle both reachable buckets and unreachable locations. My feedback is focused on improving the testing practices by removing a redundant assertion in the new system test.