Add a mechanism to silence noisy s3 simulator logs

[G-D-Petrov]

Reference Issues/PRs

What does this implement or fix?

The s3 simulator generates a lot of noisy logs for all HTTP requests against it like:

127.0.0.1 - - [27/Feb/2026 17:22:32] "GET /test-s3-bucket-1772205700-1/local/lib-AaRpA-1-False-source/ver/*sTt*test_stress_version_map_compact[False-1]2026-02-27T15_22_01_443079*111*1772205752094781585*862829297724738019*0*0 HTTP/1.1" 200 -
127.0.0.1 - - [27/Feb/2026 17:22:32] "GET /test-s3-bucket-1772205700-1/local/lib-AaRpA-1-False-source/ver/*sTt*test_stress_version_map_compact[False-1]2026-02-27T15_22_01_443079*56*1772205752446032834*13228741650102877386*0*0 HTTP/1.1" 200 -
127.0.0.1 - - [27/Feb/2026 17:22:32] "GET /test-s3-bucket-1772205700-1?list-type=2&prefix=local/lib-AaRpA-1-False-source/tref/ HTTP/1.1" 200 -

In many cases, these logs are not useful and are just filling up the logs, making it harder to debug the actual problem.
This PR adds a way to disable the logs(redirecting them using _suppress_moto_server_stdio) and disables them by default.

Any other comments?

Checklist

Checklist for code changes...

• Have you updated the relevant docstrings, documentation and copyright notice?
• Is this contribution tested against all ArcticDB's features?
• Do all exceptions introduced raise appropriate error messages?
• Are API changes highlighted in the PR description?
• Is the PR labelled as enhancement or bug so it appears in autogenerated release notes?

[claude]

ArcticDB Code Review Summary

API and Compatibility

• No breaking changes to public Python API
• Deprecation protocol followed for removed/renamed parameters
• On-disk format unchanged (or migration path documented)
• Protobuf schema backwards-compatible
• Key types and ValueType enum unchanged (or additive only)

Memory and Safety

• RAII used for all resource management (_suppress_moto_server_stdio uses os.dup2 inside the with open(os.devnull) block while the fd is still valid)
• No use-after-move or use-after-free patterns
• Buffer size calculations correct (no overflow potential)
• GIL correctly managed at Python-C++ boundary
• No accidental copies of large objects

Correctness

• All ValueType/KeyType switch statements exhaustive (N/A)
• Edge cases handled
• run_s3_server and run_gcp_server call _configure_moto_server_logging and _suppress_moto_server_stdio correctly
• Fixed (18b9b3a) " strtobool(os.getenv("ARCTICDB_MOTO_VERBOSE ", " ")) " now correctly reads the env var value before converting to bool (previously " strtobool(" ARCTICDB_MOTO_VERBOSE " ) " converted the literal key name, permanently forcing verbose = False)
• Error codes unique and in correct ErrorCategory (N/A)
• Storage backend interface fully implemented (N/A)
• Query clause composition correct (N/A)

Code Quality

• No duplicated logic - _is_truthy_env removed; arcticdb.util.utils.strtobool now used correctly
• Nit: _QuietMotoRequestHandler.log_error calls super().log_error(format, *args) - identical to base-class behaviour; the override adds no value and can be removed
• C++ and Python implementations of shared concepts are consistent (N/A)
• Tests are not duplicating existing test scenarios

Testing

• Behavioural changes have corresponding tests - no tests added for the new suppression logic or the ARCTICDB_MOTO_VERBOSE env-var toggle
• Edge cases covered in tests (N/A for this change)
• Integration tests for storage/version engine changes (N/A)
• No regression in existing test expectations

Build and Dependencies

• New source files added to CMakeLists.txt (N/A)
• Dependency changes justified and version-pinned (N/A - werkzeug.serving is already a transitive dep)
• Cross-platform compatibility maintained

Security

• No hardcoded credentials or secrets
• Input validation at system boundaries
• No buffer overflow potential in C++ code

PR Title and Description

• Title is clear, concise, and uses imperative verb
• Title and description are free of typos and grammatical errors
• Description explains what changed and why
• All significant changes in the diff are mentioned in the description - _suppress_moto_server_stdio (full stdio redirect via os.dup2) is not mentioned
• API/breaking changes explicitly called out in the description (N/A)
• Linked issues referenced where applicable - no issue linked
• PR checklist items filled in

Documentation

• Public API docstrings accurate (N/A)
• Breaking changes flagged with appropriate labels (N/A)

---

Summary

Commit 18b9b3a fixes the one blocking bug introduced in c46a499:

1. " Fixed (18b9b3a) - env var now correctly read " - Both run_s3_server and run_gcp_server now use strtobool(os.getenv("ARCTICDB_MOTO_VERBOSE ", " ")). When the var is unset, os.getenv returns " " and strtobool( " " ) returns False, so log suppression is on by default. When set to " true " / " 1 " /etc., verbose mode is enabled as intended. No blocking issues remain.

Previously fixed (still good):

• Closed-file-handle crash in _suppress_moto_server_stdio (fixed via os.dup2)
• TypeError from calling logging helpers without the verbose argument

Remaining non-blocking items:

• _QuietMotoRequestHandler.log_error is dead code (just calls super()) and can be removed
• No tests for the ARCTICDB_MOTO_VERBOSE toggle or suppression behaviour
• PR description does not mention the os.dup2 stdio redirect
• PR checklist not filled in

[vasil-pashov]

Claude is right about this one, strtobool only converts to true/false but does not read the env. So you'd have to os.environ.get first