Improve HTTP transport stability & logging

[VinayakTiwari1103]

This PR enhances the HTTP transport layer by improving socket handling, request throttling, and error logging. It ensures better stability, optimizes reconnections, and improves debugging capabilities.
Key Changes

• Improved socket reconnection logic to handle timeouts more effectively.
• Enhanced request throttling mechanism for smoother API interactions.
• Refactored logging for better traceability and debugging.
• Addressed potential connection closure issues across different OS environments.

Testing Details

• The changes were tested locally using RESTler, as our CI workflow does not support long-running tests.
• Request coverage verification was done manually to ensure expected behavior.
• Noted that the GitHub workflow test failed due to the expected output (Request coverage (successful / total): 6 / 6) not being found.
• Debugging ongoing: Reviewing logs in restler_working_dir/Test to identify the root cause.
• Next steps: Running RESTler with more detailed logging and updating the PR accordingly.

[VinayakTiwari1103]

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[VinayakTiwari1103]

Hi @marina-p @rifiles @PatGod , could you please review and approve the workflow when you have time? Thanks!

[marina-p]

Hi @VinayakTiwari1103 - workflow approved. Could you please comment in the PR description how you tested these changes? We currently do not have long-running tests that can be launched in the CI workflow, we usually run another set of tests separately on real-world services for larger changes like this one.

---

In reply to: 2708453414

[VinayakTiwari1103]

Hi @VinayakTiwari1103 - workflow approved. Could you please comment in the PR description how you tested these changes? We currently do not have long-running tests that can be launched in the CI workflow, we usually run another set of tests separately on real-world services for larger changes like this one.

In reply to: 2708453414

I've updated the PR description with details on how I tested these changes. Let me know if anything else is needed.

[marina-p]

FYI, the end to end test is failing due to a known issue, fix will be merged today. The engine tests do not have any known issues.

[marina-p]

Hi @VinayakTiwari1103,

For the PR description update - thank you, that is helpful. In addition, I'd like to better understand the specific bugs you have fixed with this change. This will help me suggest new regression tests.

Also, please split the cosmetic improvements into a separate PR (for example, changes to output formatting, spacing only changes, non-functional code rewrites, etc.). This will make it easier to review these and make sure they are consistent with the conventions of the project.

Thanks,

Marina

[VinayakTiwari1103]

Hi @marina-p,

Thanks for the feedback and Guidance! Here’s a more detailed breakdown of the specific issues that this PR addresses:

1. Fixed socket reconnection issues after timeouts

• Previously, when a request timeout occurred, the socket would sometimes fail to reconnect correctly, leading to intermittent failures.
• The new logic ensures that after a timeout, the socket is properly closed and re-established before retrying the request.
• This prevents dropped requests and improves the reliability of long-running RESTler fuzzing sessions.

2. Addressed connection closure inconsistencies across different OS environments

• The handling of persistent connections varied between Windows and Linux which causing different behaviors in connection termination.
• In some cases, lingering connections were not closed properly, leading to resource exhaustion or unexpected errors.
• This fix standardizes the connection shutdown process, ensuring graceful closure across all supported platforms.

3. Improved request throttling logic to prevent API overload and optimize retries

• The existing throttling mechanism did not efficiently manage API rate limits, leading to occasional bursts of excessive requests.
• This update introduces an adaptive throttling mechanism that dynamically adjusts request pacing based on response latency and server load.
• As a result, RESTler now interacts more smoothly with APIs, reducing the risk of triggering rate limits or getting blocked.

I’ve also noted your request to separate cosmetic changes into a different PR and will do so accordingly.

Regarding the failing end-to-end tests, I’ll re-run them once the known issue fix is merged and update the PR accordingly.

Let me know if you need any further clarifications!

Best,
Vinayak

[VinayakTiwari1103]

Hi @marina-p,

I wanted to check if there are any further updates needed from my side for this PR. I have already addressed your feedback regarding the specific fixes and separated the cosmetic changes into a different PR.

Also, I noticed that the required checks are still pending. Could you please confirm if there are any additional steps I should take, or if this is something that needs to be addressed from the maintainers' side?

Let me know if any other modifications or clarifications are required!

Best,
Vinayak

[marina-p]

Hi @VinayakTiwari1103,

I see two commits in the PR, but they appear identical for me. Could you please check that you pushed the commit with the latest updates? Let me know if I'm missing something.

RE: the checks, apologies for the delay. I am still trying to figure out how to enable checks to trigger automatically for anyone who submits a PR (this was the case when the PR checks were linked to an ADO project, but no longer after migrating to GitHub actions). For now, the fastest option will be for you to run unit tests locally and get them to pass.

Thanks,

Marina

[VinayakTiwari1103]

Hi @marina-p,

Thanks for reviewing the PR! I'll double-check the commits and ensure that the latest updates are correctly pushed. I'll update you shortly once I've verified.

Regarding the checks, no worries! I'll run the unit tests locally and confirm that everything passes. Let me know if there’s anything else I should keep in mind while running them.

Best,
Vinayak