fix: add timeout handling for subprocess wait

[quinna-h]

After subprocess is opened, wait and kill if Timeout is exceeded to ensure zombie processes are killed.

Checklist

• PR author has checked that all the criteria below are met
• The PR description includes an overview of the change
• The PR description articulates the motivation for the change
• The change includes tests OR the PR description describes a testing strategy
• The PR description notes risks associated with the change, if any
• Newly-added code is easy to change
• The change follows the library release note guidelines
• The change includes or references documentation updates if necessary
• Backport labels are set (if applicable)

Reviewer Checklist

• Reviewer has checked that all the criteria below are met
• Title is accurate
• All changes are related to the pull request's stated goal
• Avoids breaking API changes
• Testing strategy adequately addresses listed risks
• Newly-added code is easy to change
• Release note makes sense to a user of the library
• If necessary, author has acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment
• Backport labels are set in a manner that is consistent with the release branch maintenance policy

https://datadoghq.atlassian.net/browse/APMLP-313

[github-actions]

CODEOWNERS have been resolved as:

releasenotes/notes/fix-lib-injection-zombie-dc16ca6c8bf50edb.yaml       @DataDog/apm-python
lib-injection/sources/sitecustomize.py                                  @DataDog/apm-core-python

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 3.67%. Comparing base (274e6f2) to head (838c532).

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #12806      +/-   ##
==========================================
- Coverage    3.67%    3.67%   -0.01%     
==========================================
  Files        1378     1378              
  Lines      135899   135899              
==========================================
- Hits         4992     4990       -2     
- Misses     130907   130909       +2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[github-actions]

Bootstrap import analysis

Comparison of import times between this PR and main.

Summary

The average import time in this PR is: 234 ± 4 ms.

The average import time in main is: 234 ± 3 ms.

The import time difference between this PR and main is: -0.0 ± 0.2 ms.

The difference is not statistically significant (z = -0.22).

Import time breakdown

The following import paths have shrunk:

ddtrace.auto 1.856 ms (0.79%)

ddtrace.bootstrap.sitecustomize 1.256 ms (0.54%)

ddtrace.bootstrap.preload 1.256 ms (0.54%)

ddtrace.internal.products 1.256 ms (0.54%)

ddtrace.internal.remoteconfig.client 0.640 ms (0.27%)

ddtrace 0.600 ms (0.26%)

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-03-26 14:32:25

Comparing candidate commit af150ac in PR branch quinna.halim/kill-zombie-telemetry-process with baseline commit efa4325 in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 498 metrics, 2 unstable metrics.

[Copilot]

Pull Request Overview

This PR introduces timeout handling for subprocess waits to ensure that any spawned subprocesses are terminated when a timeout is exceeded and to avoid zombie processes. Key changes include renaming the internal telemetry sending function to _send_telemetry, adding a try/finally block to properly close subprocess streams, and implementing a timeout check using p.wait(1) for Python versions 3.3 and above.

[pawelchcki]

One small comment about older Pythons Timeout.

Since its a small subset of places where we run - and this should also be handled by some of the injector guardrails.

I'll mark this PR as approved. But it would still be good to fix this timeout.

[natitsechanski]

lgtm