fix: Improve input size validation for large HTTP JSON requests

[pskiran1]

What does the PR do?

This change addresses an issue where an excessively large HTTP JSON payload could cause an unhandled std::length_error exception and terminate the server unexpectedly.
A validation check is now performed in the EVBufferToJson function. It compares the incoming JSON data size against the configured --http-max-input-size limit. Requests that exceed this limit are now gracefully rejected.

• A new test case has been added to test the failing scenario.
• Existing test cases have been updated, ensuring that the entire request JSON is within the --http-max-input-size limit.

Checklist

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• build
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Test plan:

• CI Pipeline ID: 36107617

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Background

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• closes GitHub issue: #xxx

[Copilot]

Pull Request Overview

This PR fixes a server crash issue by adding input size validation for large HTTP JSON requests. The change prevents std::length_error exceptions by checking the JSON payload size against the configured --http-max-input-size limit before processing.

• Added validation check in EVBufferToJson function to compare incoming JSON size against the maximum allowed size
• Updated test cases to verify the new error handling behavior
• Added new test case specifically for large string payloads in JSON requests

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/http_server.cc	Added size validation check with descriptive error message
qa/L0_http/test.sh	Added test execution for large string in JSON scenario
qa/L0_http/http_test.py	Updated error message assertions to match new validation
qa/L0_http/http_input_size_limit_test.py	Added new test case and debug logging for large string payloads
qa/L0_cuda_shared_memory/cuda_shared_memory_test.py	Updated error message assertions to match new validation

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[Copilot]

Pull Request Overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

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[whoisj]

LGTM and Matt already commented on everything that I noticed 👍

[yinggeh]

LGTM

[mattwittwer]

LGTM