feat: persist authored action idempotency (#201)

tests/test_authored_idempotency.py

@@ -4,13 +4,16 @@ import httpx
 import pytest
 
 from src import main
+from src.idempotency import IdempotencyLedger
 
 
 @pytest.fixture(autouse=True)
 def clear_authored_operations():
     main._authored_action_operations.clear()
+    main._idempotency_ledger.clear()
     yield
     main._authored_action_operations.clear()
+    main._idempotency_ledger.clear()
 
 
 @pytest.mark.anyio
@@ -140,3 +143,88 @@ async def test_review_replays_same_key_and_rejects_changed_head(monkeypatch):
 
     assert [created.status_code, replayed.status_code, conflict.status_code] == [201, 201, 409]
     assert calls == [("abc", "approve", "Good")]
+
+
+@pytest.mark.anyio
+async def test_completed_comment_replays_after_ledger_reconstruction(monkeypatch, tmp_path):
+    calls = 0
+
+    async def assigned(_repository, _number):
+        return True
+
+    async def comment(_repository, _number, body):
+        nonlocal calls
+        calls += 1
+        return {"id": 201, "body": body}
+
+    database = tmp_path / "actions.sqlite3"
+    monkeypatch.setattr(
+        main,
+        "_idempotency_ledger",
+        IdempotencyLedger(database, ttl_seconds=600, max_entries=256),
+        raising=False,
+    )
+    monkeypatch.setattr(main.gitea_proxy, "is_assigned_issue", assigned)
+    monkeypatch.setattr(main.gitea_proxy, "comment_on_issue", comment)
+    transport = httpx.ASGITransport(app=main.app)
+    headers = {"Idempotency-Key": "restart-comment-201"}
+
+    async with httpx.AsyncClient(transport=transport, base_url="http://test") as client:
+        created = await client.post(
+            "/api/v1/repos/stackchain/api/issues/7/comments",
+            json={"body": "Persist me"},
+            headers=headers,
+        )
+        main._authored_action_operations.clear()
+        monkeypatch.setattr(
+            main,
+            "_idempotency_ledger",
+            IdempotencyLedger(database, ttl_seconds=600, max_entries=256),
+        )
+        replayed = await client.post(
+            "/api/v1/repos/stackchain/api/issues/7/comments",
+            json={"body": "Persist me"},
+            headers=headers,
+        )
+
+    assert [created.status_code, replayed.status_code] == [201, 201]
+    assert replayed.json() == {"id": 201, "body": "Persist me"}
+    assert calls == 1
+
+
+@pytest.mark.anyio
+async def test_orphaned_pending_comment_fails_closed_without_upstream_retry(
+    monkeypatch, tmp_path
+):
+    calls = 0
+
+    async def assigned(_repository, _number):
+        return True
+
+    async def comment(_repository, _number, body):
+        nonlocal calls
+        calls += 1
+        return {"id": 202, "body": body}
+
+    ledger = IdempotencyLedger(
+        tmp_path / "orphan.sqlite3", ttl_seconds=600, max_entries=256
+    )
+    fingerprint = ("issue-comment", "stackchain/api", 7, "Verify first")
+    assert ledger.reserve("orphan-comment-201", fingerprint).state == "reserved"
+    monkeypatch.setattr(main, "_idempotency_ledger", ledger)
+    monkeypatch.setattr(main.gitea_proxy, "is_assigned_issue", assigned)
+    monkeypatch.setattr(main.gitea_proxy, "comment_on_issue", comment)
+    transport = httpx.ASGITransport(app=main.app)
+
+    async with httpx.AsyncClient(transport=transport, base_url="http://test") as client:
+        response = await client.post(
+            "/api/v1/repos/stackchain/api/issues/7/comments",
+            json={"body": "Verify first"},
+            headers={"Idempotency-Key": "orphan-comment-201"},
+        )
+
+    assert response.status_code == 503
+    assert response.json()["detail"] == (
+        "This action may still be completing; verify its result before retrying"
+    )
+    assert calls == 0

tests/test_idempotency_ledger.py

@@ -0,0 +1,73 @@
+import sqlite3
+from concurrent.futures import ThreadPoolExecutor
+from threading import Barrier
+
+from src.idempotency import IdempotencyLedger
+
+
+def test_completed_result_replays_after_ledger_reconstruction(tmp_path):
+    database = tmp_path / "idempotency.sqlite3"
+    first = IdempotencyLedger(database, ttl_seconds=600, max_entries=256)
+
+    reservation = first.reserve("create-201", ("issue-create", "stackchain/api", "Ship it"))
+    assert reservation.state == "reserved"
+    first.complete("create-201", {"number": 42, "title": "Ship it"})
+
+    reconstructed = IdempotencyLedger(database, ttl_seconds=600, max_entries=256)
+    replay = reconstructed.reserve(
+        "create-201", ("issue-create", "stackchain/api", "Ship it")
+    )
+
+    assert replay.state == "completed"
+    assert replay.response == {"number": 42, "title": "Ship it"}
+    assert sqlite3.connect(database).execute(
+        "SELECT status FROM idempotency_operations WHERE key = ?", ("create-201",)
+    ).fetchone() == ("completed",)
+
+
+def test_reservation_expires_completed_rows_and_enforces_capacity(tmp_path):
+    now = [1_000.0]
+    ledger = IdempotencyLedger(
+        tmp_path / "bounded.sqlite3",
+        ttl_seconds=10,
+        max_entries=2,
+        clock=lambda: now[0],
+    )
+    assert ledger.reserve("old", ("comment", "old")).state == "reserved"
+    ledger.complete("old", {"id": 1})
+    now[0] += 11
+
+    assert ledger.reserve("new-1", ("comment", "new-1")).state == "reserved"
+    ledger.complete("new-1", {"id": 2})
+    assert ledger.reserve("new-2", ("comment", "new-2")).state == "reserved"
+    ledger.complete("new-2", {"id": 3})
+    replacement = ledger.reserve("new-3", ("comment", "new-3"))
+
+    assert replacement.state == "reserved"
+    with sqlite3.connect(ledger.path) as connection:
+        keys = connection.execute(
+            "SELECT key FROM idempotency_operations ORDER BY key"
+        ).fetchall()
+        indexes = connection.execute(
+            "PRAGMA index_list(idempotency_operations)"
+        ).fetchall()
+    assert keys == [("new-2",), ("new-3",)]
+    assert any(index[1] == "idempotency_completed_at_idx" for index in indexes)
+
+
+def test_independent_connections_atomically_reserve_one_operation(tmp_path):
+    database = tmp_path / "workers.sqlite3"
+    ledgers = [
+        IdempotencyLedger(database, ttl_seconds=600, max_entries=256)
+        for _ in range(2)
+    ]
+    barrier = Barrier(2)
+
+    def reserve(ledger):
+        barrier.wait()
+        return ledger.reserve("worker-key-201", ("review", "stackchain/api", 7)).state
+
+    with ThreadPoolExecutor(max_workers=2) as executor:
+        states = list(executor.map(reserve, ledgers))
+
+    assert sorted(states) == ["pending", "reserved"]

tests/test_issue_api.py

@@ -5,6 +5,7 @@ import httpx
 import pytest
 
 from src import gitea_proxy, main
+from src.idempotency import IdempotencyLedger
 
 
 @pytest.mark.anyio
@@ -226,9 +227,11 @@ async def test_edit_assigned_issue_reports_revision_conflict_without_mutation(mo
 
 @pytest.fixture(autouse=True)
 def clear_issue_creation_operations():
-    main._issue_creation_operations.clear()
+    main._authored_action_operations.clear()
+    main._idempotency_ledger.clear()
     yield
-    main._issue_creation_operations.clear()
+    main._authored_action_operations.clear()
+    main._idempotency_ledger.clear()
 
 
 @pytest.mark.anyio
@@ -331,6 +334,61 @@ async def test_create_issue_replays_one_upstream_result_for_concurrent_idempoten
     assert calls == 1
 
 
+@pytest.mark.anyio
+async def test_completed_issue_creation_replays_after_ledger_reconstruction(monkeypatch, tmp_path):
+    calls = 0
+
+    async def user():
+        return {"login": "timmy"}
+
+    async def available_repos():
+        return [{"full_name": "stackchain/api"}]
+
+    async def create(repository, title, body, assignee, label_ids):
+        nonlocal calls
+        calls += 1
+        return {
+            "id": 201, "number": 201, "title": title, "state": "open",
+            "repository": repository, "labels": [], "assignees": [assignee],
+            "updated_at": "2026-08-07T15:00:00Z",
+            "url": "https://forge.example/stackchain/api/issues/201",
+        }
+
+    database = tmp_path / "issues.sqlite3"
+    monkeypatch.setattr(
+        main,
+        "_idempotency_ledger",
+        IdempotencyLedger(database, ttl_seconds=600, max_entries=256),
+    )
+    monkeypatch.setattr(main.gitea_proxy, "current_user", user)
+    monkeypatch.setattr(main.gitea_proxy, "repos", available_repos)
+    monkeypatch.setattr(main.gitea_proxy, "create_issue", create)
+    transport = httpx.ASGITransport(app=main.app)
+    headers = {"Idempotency-Key": "restart-create-201"}
+
+    async with httpx.AsyncClient(transport=transport, base_url="http://test") as client:
+        created = await client.post(
+            "/api/v1/repos/stackchain/api/issues",
+            json={"title": "Durable capture"},
+            headers=headers,
+        )
+        main._authored_action_operations.clear()
+        monkeypatch.setattr(
+            main,
+            "_idempotency_ledger",
+            IdempotencyLedger(database, ttl_seconds=600, max_entries=256),
+        )
+        replayed = await client.post(
+            "/api/v1/repos/stackchain/api/issues",
+            json={"title": "Durable capture"},
+            headers=headers,
+        )
+
+    assert [created.status_code, replayed.status_code] == [201, 201]
+    assert replayed.json()["number"] == 201
+    assert calls == 1
+
+
 @pytest.mark.anyio
 async def test_create_issue_rejects_changed_payload_for_an_existing_idempotency_key(monkeypatch):
     calls = []
@@ -412,7 +470,9 @@ async def test_create_issue_retry_recovers_result_after_the_first_request_times_
 
 
 @pytest.mark.anyio
-async def test_create_issue_idempotency_registry_evicts_oldest_entry_at_size_limit(monkeypatch):
+async def test_create_issue_durable_ledger_evicts_completed_entry_at_size_limit(
+    monkeypatch, tmp_path
+):
     async def user():
         return {"login": "timmy"}
 
@@ -427,7 +487,10 @@ async def test_create_issue_idempotency_registry_evicts_oldest_entry_at_size_lim
             "url": "https://forge.example/stackchain/api/issues/17",
         }
 
-    monkeypatch.setattr(main, "ISSUE_CREATION_IDEMPOTENCY_MAX_ENTRIES", 2)
+    ledger = IdempotencyLedger(
+        tmp_path / "bounded-issues.sqlite3", ttl_seconds=600, max_entries=2
+    )
+    monkeypatch.setattr(main, "_idempotency_ledger", ledger)
     monkeypatch.setattr(main.gitea_proxy, "current_user", user)
     monkeypatch.setattr(main.gitea_proxy, "repos", available_repos)
     monkeypatch.setattr(main.gitea_proxy, "create_issue", create)
@@ -441,8 +504,11 @@ async def test_create_issue_idempotency_registry_evicts_oldest_entry_at_size_lim
             )
             assert response.status_code == 201
 
-    assert len(main._issue_creation_operations) == 2
-    assert "capture-177-bounded-0" not in main._issue_creation_operations
+    replay = ledger.reserve(
+        "capture-177-bounded-0",
+        ("issue-create", "stackchain/api", "Capture 0", "", ()),
+    )
+    assert replay.state == "reserved"
 
 
 @pytest.mark.anyio