make write004 safer

[mr-git]

Change the effect wrapping from .delay to .blocking as scraping of metrics might include blocking call(s).

For example the downstream user might add own metric which reads file on .collect.

Summary by CodeRabbit

• Bug Fixes
  • Improved the reliability of Prometheus metric output generation by running serialization in a blocking-safe context.
  • Standardized metric text encoding to UTF-8 for consistent output.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 89765280-284a-4f52-92e4-654a00caea7d

📥 Commits

Reviewing files that changed from the base of the PR and between eb0c6ff and 5b5c923.

📒 Files selected for processing (2)

• modules/prometheus/src/main/scala/com/evolutiongaming/smetrics/Prometheus.scala
• modules/prometheus_v1/src/main/scala/com/evolutiongaming/smetrics/Prometheus.scala

Included review availability: Your plan provides up to 10 included reviews per hour; 9 remain after this review.

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📝 Walkthrough

Walkthrough

Prometheus text serialization now runs inside Sync[F].blocking in both modules. The v1 implementation also uses StandardCharsets.UTF_8 for output decoding.

Changes

Prometheus serialization

Layer / File(s)	Summary
Blocking serialization and UTF-8 decoding modules/prometheus/src/main/scala/com/evolutiongaming/smetrics/Prometheus.scala, modules/prometheus_v1/src/main/scala/com/evolutiongaming/smetrics/Prometheus.scala	Both implementations use Sync[F].blocking for serialization. The v1 implementation uses explicit UTF-8 decoding. Scraping and timestamp settings remain unchanged.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Merge Risk: ⚪ Minimal · up to 5b5c9

This is a small, localized change to metric collection behavior, and no actionable merge-blocking risk remains after normal checks and review.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the main change: making write004 safer by using blocking effect execution.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch m/make-write004-blocking

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