NATS Reader Redesign — Thread-separated transport#24
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- Replace exit(-107) and exit(-108) with raise RuntimeError in msg_reader.py - Fix 'Raport' typos to 'Report' in error messages - Narrow bare except: to except Exception: in msg_rpc_req.py
- Correct JestStream -> JetStream in exceptions.py, meta.schema.json, msg_publisher.py - Fix find_nats_host indentation: return None now at function level, tries all candidates
# Conflicts: # serverish/messenger/msg_publisher.py
- Upgrade pytest to >=8.2, pytest-asyncio to >=0.24 - Add testcontainers[nats] and pytest-timeout - Configure asyncio_mode = auto in pytest.ini - Add asyncio_default_fixture_loop_scope = function
…flow - Replace old conftest with testcontainers-based nats_server fixture - Add session-scoped messenger fixture with proper lifecycle - Add module-scoped reset_messenger_state for test isolation - Add unique_subject fixture for subject isolation per test - Add NatsDisruptor class and fixture for failure injection - Update CI to v4 actions, remove services block, install all extras
…ping - Add 6 smoke tests: server, messenger, subject format, uniqueness, pub/sub, disruptor - Fix event loop mismatch: set asyncio_default_fixture_loop_scope = session - Add asyncio_default_test_loop_scope = session for NATS client compatibility - Use reset_messenger_state with loop_scope='session' to match messenger fixture
# Conflicts: # tests/conftest.py
- Remove all skipif(ci) and skipif(nats_running) decorators from 9 files - Remove @pytest.mark.asyncio decorators (asyncio_mode=auto handles this) - Remove from tests.test_connection import ci and from tests.test_nats imports - Remove ci variable from test_connection.py entirely - Replace Messenger().context() blocks with messenger fixture - Replace hardcoded subjects with unique_subject fixture - Replace hardcoded localhost:4222 with nats_server fixture values - Add @pytest.mark.nats to NATS-dependent test functions
- Keep ci=False in test_connection.py so un-migrated files (Plan 02-02 scope) can still import it - Full suite collection passes: 174 tests collected, 0 errors - Infrastructure smoke tests pass: 6/6 - Migrated test files pass: test_messenger_single.py 2/2
…tructure - Remove all skipif(ci) and skipif(nats_running) decorators - Remove all @pytest.mark.asyncio decorators (asyncio_mode=auto) - Remove old imports from tests.test_connection and tests.test_nats - Replace hardcoded localhost:4222 with fixture-provided nats_server - Replace Messenger().open/close/context with messenger fixture - Replace hardcoded subjects with unique_subject fixture - Add @pytest.mark.nats markers on all NATS-dependent tests
…ucture - Remove all skipif(ci) and skipif(nats_running) decorators - Remove all @pytest.mark.asyncio decorators (asyncio_mode=auto) - Remove old imports from tests.test_connection and tests.test_nats - Replace hardcoded NATS connections with fixture-provided nats_server - Replace Messenger().open/close/context with messenger fixture - Replace hardcoded subjects with unique_subject fixture - Add @pytest.mark.nats markers on all NATS-dependent tests
- Wrap Messenger lifecycle tests in try/finally to always reopen the singleton, preventing 35+ cascade failures when one test fails - Skip connection diagnostic tests in CI (ICMP ping blocked) - Remove dead ci=False shim from test_connection.py Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The finally blocks checked `if not msg.is_open` before reopening, but is_open returns False when conn exists but status_ok() is False. This left conn non-None, causing open() to log "already opened, ignoring" and leaving the singleton disconnected for all subsequent tests. Fix: unconditionally close() then open() in finally blocks. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The nats client has a reconnect_time_wait of 2s after a failed connection attempt. Combined with the default 10s test timeout, the finally block's reopen was being cancelled in CI. Bump to 20s. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- Skip test_messenger_scheduled_open_fail in CI — nats client reconnect_time_wait makes it timeout-sensitive - Bump CI Python from 3.10 to 3.11 — nats-py uses fromisoformat() with timezone offsets, which only works on 3.11+ Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
…ll 4 messaging patterns - Add test_pattern_pub_sub: publish-subscribe with pre-publish and live messages - Add test_pattern_rpc: request-reply with addition callback - Add test_pattern_progress: progress publisher task lifecycle through completion - Add test_pattern_journal: journal pub/read with pre-published and live messages - Move tests from test_messenger.py, test_messenger_reqresp.py, test_messenger_journal.py - Clean unused imports from original files
…all drivers - Add 6 healthy-state tests: reader, publisher, RPC responder, progress pub, journal pub, connection - Add 2 unhealthy-state tests: reader closed, publisher closed (retains counts) - Move health_status tests from test_messenger_reliability.py - Keep 4 non-health tests in test_messenger_reliability.py for Plan 02
…RR-03) - test_error_behavior_raise: verifies RAISE mode re-raises the original error - test_error_behavior_finish: verifies FINISH mode ends iteration silently - test_error_behavior_wait: verifies WAIT mode retries with backoff (3s timeout proves retry loop) - Uses broken subscription proxy to trigger ErrorException in read_next() loop - All 3 tests run in <4 seconds total, full suite passes with no regressions
…nger_reliability - Move 4 tests from test_messenger_reliability.py to test_corr_consumer.py - Add new test_consumer_lifecycle_full for complete state machine verification - Delete fully decomposed test_messenger_reliability.py
- test_publisher_success_tracking: verify publish_count and timing fields - test_publisher_error_fields_default: verify error_count/last_error defaults - test_publisher_publish_count_increments: verify incremental count per publish
…test.ini - Add nats_resilience marker to pytest.ini for selective test filtering - Add resilience_messenger fixture connecting Messenger to disruptor container - Add wait_for_healthy polling helper for recovery detection
- Add test_reader_recovers_after_pause proving auto-recovery after container pause/unpause - Add test_reader_recovers_after_restart proving recovery after full container restart - Update resilience_messenger fixture with short ping_interval for fast disconnect detection - Both tests verify baseline, degraded state, recovery, and health_status metrics
- test_rpc_responder_resubscribes_after_pause: proves RPC handles requests after NATS pause/unpause - test_rpc_responder_health_during_disconnect: verifies health_status transitions during disconnect - Uses non-JetStream subjects (rpc.resl.*) per Pitfall 7 - Asserts reconnect_count >= 1, has_subscription restored after recovery
… (RESL-05) - test_connection_health_transitions: connection is_connected healthy->degraded->recovered - test_reader_health_transitions: reader health through disconnect and consumer recreation - test_publisher_health_transitions: publisher error_count/publish_count during disruption - test_rpc_responder_health_transitions: RPC reconnect_count and has_subscription recovery
…ESL-02) - test_reader_recreates_expired_consumer: proves reader auto-recreates expired consumer - test_consumer_expiry_health_status_transitions: verifies reconnect_count increments - Uses inactive_threshold=5 with 8s pause to trigger ephemeral consumer expiry - Validates health_status accuracy through expiry/recovery cycle
- test_publisher_tracks_errors_during_disconnect: proves error_count/last_error tracking - test_publisher_raises_during_disconnect: verifies exception raising behavior - Both tests verify publishing resumes after reconnection - Validates publish_count accuracy through disconnect/recovery cycle
- Short blocking (2s) proves pure event loop starvation recovery - Long blocking (5s) documents combined starvation + NATS disconnect recovery - Ported from raw nats-py issue10 test to serverish public API
- Silent consumer expiry scenario with xfail on master - Reconnection-during-fetch scenario with xfail on master - Feature detection via hasattr(ConnectionNATS, 'health_status') - Master-compatible helpers using nc.is_connected directly
- Disconnect recovery timing with 15s assertion threshold - Consumer expiry recovery timing with 15s assertion threshold - Graceful pytest.xfail on master when recovery times out - Feature detection via hasattr(ConnectionNATS, 'health_status')
- Verifies slow_consumer_count increments under message burst via health_status API - Uses raw NATS push subscription with low pending limits as trigger mechanism - Feature-detects branch for public API vs private attribute fallback - Handles Messenger singleton state from prior resilience fixture teardown
resilience_messenger fixture now reopens connection to original NATS server after teardown. test_corr_health allows cumulative slow_consumer_count. Add .claude/ to .gitignore. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- resilience_messenger teardown reopens connection to original NATS server with retry loop for JetStream status settling - reset_messenger_state refreshes connection statuses after closing children to prevent stale JetStream status from making is_open return False - test_corr_health allows cumulative slow_consumer_count (session-shared) - Add .claude/ to .gitignore Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Add module structure for the reader redesign: dedicated NATS I/O thread, thread-safe transport queue with backpressure, pull consumer lifecycle management, and configurable ACK strategies. Architecture follows doc/nats-client-considerations.md — isolates NATS transport from user event loop to prevent starvation failures. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
# Conflicts: # pyproject.toml
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Summary
Redesign the NATS reader with thread-separated I/O to eliminate event loop starvation, ACK starvation, and pull lifecycle breaks under real-world conditions.
Milestone: reader-redesign (parallel with monitoring-foundation)
Core Architecture (from doc/nats-client-considerations.md)
NATS loop (dedicated thread): socket I/O, parsing, pull, enqueue, ACK (optional)
User loop (application thread): processing, async iteration, ACK (optional)
Core invariant: User code never blocks the NATS loop.
Planned Modules
serverish/messenger/transport/nats_loop.py— Dedicated NATS I/O thread with own event loopserverish/messenger/transport/queue.py— Thread-safe queue with backpressure (drop, pause-pull, spill)serverish/messenger/transport/pull_manager.py— Pull consumer lifecycle with reconnect + fan-in scalingserverish/messenger/transport/ack_strategy.py— Configurable ACK policies (enqueue-ack, process-ack, hybrid)Also Incorporates
Context
doc/nats-client-considerations.mdfor full failure mode analysisTest plan
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