Add QueueRepositoryInterface with memory and file-backed adapters.

Provide a generic disk-backed FIFO queue with configurable path, retention, and dedup keys so consumers can buffer items across restarts without optional extras.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/unit/memory_queue_adapter_test.py

@@ -0,0 +1,144 @@
+"""Unit tests for MemoryQueueAdapter."""
+
+from __future__ import annotations
+
+from datetime import UTC, datetime, timedelta
+import threading
+
+import pytest
+
+from python_repositories.adapters.memory_queue_adapter import (
+    MemoryQueueAdapter,
+    _parse_age,
+)
+from python_repositories.interfaces.queue_repository_interface import (
+    QueueRepositoryInterface,
+)
+
+
+def test_implements_interface() -> None:
+    assert issubclass(MemoryQueueAdapter, QueueRepositoryInterface)
+
+
+def test_fifo_without_dedup() -> None:
+    queue = MemoryQueueAdapter()
+    queue.enqueue([{"id": 1}, {"id": 2}, {"id": 3}])
+    assert queue.size() == 3
+    assert queue.dequeue_batch(max_items=2) == [{"id": 1}, {"id": 2}]
+    assert queue.dequeue_batch(max_items=10) == [{"id": 3}]
+    assert queue.dequeue_batch() == []
+    assert queue.size() == 0
+
+
+def test_empty_enqueue_is_noop() -> None:
+    queue = MemoryQueueAdapter()
+    queue.enqueue([])
+    assert queue.size() == 0
+    assert queue.enqueue_and_return_added([]) == []
+
+
+def test_dedup_keeps_first() -> None:
+    queue = MemoryQueueAdapter(dedup_keys=("id",))
+    queue.enqueue([{"id": 1, "v": "a"}, {"id": 1, "v": "b"}, {"id": 2, "v": "c"}])
+    assert queue.size() == 2
+    assert queue.dequeue_batch(max_items=10) == [
+        {"id": 1, "v": "a"},
+        {"id": 2, "v": "c"},
+    ]
+
+
+def test_missing_dedup_key_raises() -> None:
+    queue = MemoryQueueAdapter(dedup_keys=("id",))
+    with pytest.raises(ValueError, match="missing dedup key"):
+        queue.enqueue([{"name": "x"}])
+
+
+def test_missing_age_key_raises() -> None:
+    queue = MemoryQueueAdapter(age_key="created_at")
+    with pytest.raises(ValueError, match="missing age key"):
+        queue.enqueue([{"id": 1}])
+
+
+def test_evict_older_than() -> None:
+    queue = MemoryQueueAdapter(age_key="created_at", dedup_keys=("id",))
+    now = datetime.now(UTC)
+    queue.enqueue(
+        [
+            {"id": 1, "created_at": now - timedelta(hours=2)},
+            {"id": 2, "created_at": now - timedelta(minutes=30)},
+            {"id": 3, "created_at": (now - timedelta(hours=3)).isoformat()},
+        ]
+    )
+    removed = queue.evict_older_than(now - timedelta(hours=1))
+    assert removed == 2
+    assert queue.size() == 1
+    remaining = queue.dequeue_batch(max_items=10)
+    assert remaining[0]["id"] == 2
+
+
+def test_evict_without_age_key_is_noop() -> None:
+    queue = MemoryQueueAdapter()
+    queue.enqueue([{"id": 1}])
+    assert queue.evict_older_than(datetime.now(UTC)) == 0
+    assert queue.size() == 1
+
+
+def test_parse_age_rejects_unsupported_type() -> None:
+    with pytest.raises(ValueError, match="age value must be"):
+        _parse_age(123)
+
+
+def test_parse_age_aware_datetime() -> None:
+    from datetime import timezone
+
+    eastern = timezone(timedelta(hours=-5))
+    aware = datetime(2024, 1, 1, 12, 0, 0, tzinfo=eastern)
+    assert _parse_age(aware) == datetime(2024, 1, 1, 17, 0, 0, tzinfo=UTC)
+
+
+def test_parse_age_naive_datetime() -> None:
+    naive = datetime(2024, 1, 1, 12, 0, 0)
+    assert _parse_age(naive) == datetime(2024, 1, 1, 12, 0, 0, tzinfo=UTC)
+
+
+def test_parse_age_zulu_string() -> None:
+    assert _parse_age("2024-01-01T00:00:00Z") == datetime(2024, 1, 1, 0, 0, 0, tzinfo=UTC)
+
+
+def test_parse_age_naive_string() -> None:
+    assert _parse_age("2024-01-01T00:00:00") == datetime(2024, 1, 1, 0, 0, 0, tzinfo=UTC)
+
+
+def test_dequeue_rejects_negative_max_items() -> None:
+    queue = MemoryQueueAdapter()
+    with pytest.raises(ValueError, match="max_items"):
+        queue.dequeue_batch(max_items=-1)
+
+
+def test_clear_and_snapshot() -> None:
+    queue = MemoryQueueAdapter()
+    queue.enqueue([{"id": 1}, {"id": 2}])
+    assert queue.snapshot() == [{"id": 1}, {"id": 2}]
+    queue.clear()
+    assert queue.size() == 0
+    assert queue.snapshot() == []
+
+
+def test_thread_safety_smoke() -> None:
+    queue = MemoryQueueAdapter(dedup_keys=("id",))
+    errors: list[BaseException] = []
+
+    def worker(start: int) -> None:
+        try:
+            for i in range(start, start + 50):
+                queue.enqueue([{"id": i}])
+        except BaseException as exc:  # noqa: BLE001
+            errors.append(exc)
+
+    threads = [threading.Thread(target=worker, args=(i * 50,)) for i in range(4)]
+    for thread in threads:
+        thread.start()
+    for thread in threads:
+        thread.join()
+    assert errors == []
+    assert queue.size() == 200