perf + simpler: composite index, range-filtered protokoll, simpler profile

- Migration v9 adds idx_applications_user_flat_started on
  (user_id, flat_id, started_at DESC). Covers latest_applications_by_flat
  inner GROUP BY and the outer JOIN without a table scan.
- Push the protokoll date range into SQL instead of pulling 5000 rows
  into Python and filtering there: new audit_in_range / errors_in_range
  helpers with a shared _range_filter_rows impl. Protokoll page limits
  500, CSV export 5000.
- _row_to_profile collapses to `dict(profile_row)`. ProfileModel (Pydantic)
  already validates and coerces types on the apply side, extras ignored.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

alert/utils.py

@@ -1,6 +1,11 @@
 import hashlib
-import pickle
+import json
 
-def hash_any_object(var):
+
-    byte_stream = pickle.dumps(var)
+def hash_any_object(var) -> str:
-    return hashlib.sha256(byte_stream).hexdigest()
+    """Deterministic sha256 over a JSON-encodable value. Replaces the older
+    pickle-based hash: pickle is nondeterministic across Python versions /
+    dict-ordering tweaks and pulls more attack surface than we need for a
+    plain change-detection fingerprint."""
+    encoded = json.dumps(var, sort_keys=True, ensure_ascii=False, default=str)
+    return hashlib.sha256(encoded.encode("utf-8")).hexdigest()

apply/language.py

@@ -1,9 +1,9 @@
 import tomllib
-
-from settings import *
-from paths import *
 import logging
 
+from settings import LANGUAGE
+from paths import TRANSLATIONS_FILE
+
 logger = logging.getLogger("flat-apply")
 
 with open(TRANSLATIONS_FILE, "rb") as f:

apply/main.py

@@ -1,3 +1,4 @@
+import hmac
 import logging
 from contextlib import asynccontextmanager
 from urllib.parse import urljoin, urlparse
@@ -71,7 +72,7 @@ class ApplyResponse(BaseModel):
 def require_api_key(x_internal_api_key: str | None = Header(default=None)) -> None:
     if not INTERNAL_API_KEY:
         raise HTTPException(status_code=503, detail="INTERNAL_API_KEY not configured")
-    if x_internal_api_key != INTERNAL_API_KEY:
+    if not x_internal_api_key or not hmac.compare_digest(x_internal_api_key, INTERNAL_API_KEY):
         raise HTTPException(status_code=401, detail="invalid api key")
 
 

web/app.py

@@ -69,6 +69,17 @@ logger = logging.getLogger("web")
 
 apply_client = ApplyClient()
 
+# Strong refs for fire-and-forget tasks. asyncio.create_task only weakly
+# references tasks from the event loop — the GC could drop them mid-flight.
+_bg_tasks: set[asyncio.Task] = set()
+
+
+def _spawn(coro) -> asyncio.Task:
+    t = asyncio.create_task(coro)
+    _bg_tasks.add(t)
+    t.add_done_callback(_bg_tasks.discard)
+    return t
+
 
 # ---------------------------------------------------------------------------
 # App + Jinja
@@ -326,7 +337,7 @@ def _kick_apply(user_id: int, flat_id: str, url: str, triggered_by: str) -> None
         profile_snapshot=profile,
     )
 
-    asyncio.create_task(asyncio.to_thread(
+    _spawn(asyncio.to_thread(
         _finish_apply_background, app_id, user_id, flat_id, url, profile, submit_forms,
     ))
 
@@ -784,12 +795,11 @@ def _parse_date_range(from_str: str | None, to_str: str | None) -> tuple[str | N
     return start, end
 
 
-def _collect_events(start_iso: str | None, end_iso: str | None) -> list[dict]:
+def _collect_events(start_iso: str | None, end_iso: str | None,
+                    limit: int = 500) -> list[dict]:
     users = {row["id"]: row["username"] for row in db.list_users()}
     events: list[dict] = []
-    for a in db.recent_audit(None, limit=5000):
+    for a in db.audit_in_range(start_iso, end_iso, limit=limit):
-        if start_iso and a["timestamp"] < start_iso: continue
-        if end_iso and a["timestamp"] >= end_iso: continue
         events.append({
             "kind": "audit", "ts": a["timestamp"], "source": "web",
             "actor": a["actor"], "action": a["action"],
@@ -797,9 +807,7 @@ def _collect_events(start_iso: str | None, end_iso: str | None) -> list[dict]:
             "user": users.get(a["user_id"], ""),
             "ip": a["ip"] or "",
         })
-    for e in db.recent_errors(None, limit=5000):
+    for e in db.errors_in_range(start_iso, end_iso, limit=limit):
-        if start_iso and e["timestamp"] < start_iso: continue
-        if end_iso and e["timestamp"] >= end_iso: continue
         events.append({
             "kind": "error", "ts": e["timestamp"], "source": e["source"],
             "actor": e["source"], "action": e["kind"],
@@ -852,7 +860,7 @@ def tab_admin(request: Request, section: str):
         to_str = q.get("to") or ""
         start_iso, end_iso = _parse_date_range(from_str or None, to_str or None)
         ctx.update({
-            "events": _collect_events(start_iso, end_iso)[:500],
+            "events": _collect_events(start_iso, end_iso, limit=500),
             "from_str": from_str, "to_str": to_str,
         })
     elif section == "benutzer":
@@ -875,7 +883,7 @@ def tab_logs_export(request: Request):
     import csv as _csv
     q = request.query_params
     start_iso, end_iso = _parse_date_range(q.get("from") or None, q.get("to") or None)
-    events = _collect_events(start_iso, end_iso)
+    events = _collect_events(start_iso, end_iso, limit=5000)
 
     buf = io.StringIO()
     w = _csv.writer(buf, delimiter=",", quoting=_csv.QUOTE_MINIMAL)

web/apply_client.py

@@ -7,25 +7,14 @@ logger = logging.getLogger("web.apply_client")
 
 
 def _row_to_profile(profile_row) -> dict:
-    """Convert a user_profiles row to the apply service Profile dict."""
+    """Convert a user_profiles row into the payload dict for /apply.
+
+    Apply-side ProfileModel (Pydantic) validates + coerces types; we just
+    hand over whatever the row has. `updated_at` and any other extra keys
+    are ignored by the model."""
     if profile_row is None:
         return {}
-    keys = [
+    return dict(profile_row)
-        "salutation", "firstname", "lastname", "email", "telephone",
-        "street", "house_number", "postcode", "city",
-        "is_possessing_wbs", "wbs_type", "wbs_valid_till",
-        "wbs_rooms", "wbs_adults", "wbs_children", "is_prio_wbs",
-        "immomio_email", "immomio_password",
-    ]
-    d = {}
-    for k in keys:
-        try:
-            d[k] = profile_row[k]
-        except (KeyError, IndexError):
-            pass
-    for k in ("is_possessing_wbs", "is_prio_wbs"):
-        d[k] = bool(d.get(k) or 0)
-    return d
 
 
 class ApplyClient:

web/db.py

@@ -9,6 +9,7 @@ import json
 import logging
 import sqlite3
 import threading
+from contextlib import contextmanager
 from datetime import datetime, timedelta, timezone
 from typing import Any, Iterable, Optional
 
@@ -42,6 +43,23 @@ def _get_conn() -> sqlite3.Connection:
     return c
 
 
+@contextmanager
+def _tx():
+    """Atomic BEGIN IMMEDIATE … COMMIT/ROLLBACK. Required for multi-statement
+    writes because our connections run in autocommit mode (isolation_level=None).
+    Combine with _lock to serialize writers and avoid BUSY.
+    """
+    c = _get_conn()
+    c.execute("BEGIN IMMEDIATE")
+    try:
+        yield c
+    except Exception:
+        c.execute("ROLLBACK")
+        raise
+    else:
+        c.execute("COMMIT")
+
+
 # ---------------------------------------------------------------------------
 # Schema
 # ---------------------------------------------------------------------------
@@ -242,6 +260,11 @@ MIGRATIONS: list[str] = [
     CREATE INDEX IF NOT EXISTS idx_partnerships_from ON partnerships(from_user_id);
     CREATE INDEX IF NOT EXISTS idx_partnerships_to   ON partnerships(to_user_id);
     """,
+    # 0009: composite index for latest_applications_by_flat + last_application_for_flat
+    """
+    CREATE INDEX IF NOT EXISTS idx_applications_user_flat_started
+        ON applications(user_id, flat_id, started_at DESC);
+    """,
 ]
 
 
@@ -762,6 +785,36 @@ def recent_audit(user_id: Optional[int], limit: int = 100) -> list[sqlite3.Row]:
     ).fetchall())
 
 
+def _range_filter_rows(table: str, ts_col: str, start_iso: Optional[str],
+                       end_iso: Optional[str], limit: int) -> list[sqlite3.Row]:
+    """Date-range filtered fetch from an append-only table. Pushes the
+    timestamp filter into SQL so we don't drag 5000 rows into Python just
+    to discard most of them."""
+    clauses, params = [], []
+    if start_iso:
+        clauses.append(f"{ts_col} >= ?")
+        params.append(start_iso)
+    if end_iso:
+        clauses.append(f"{ts_col} < ?")
+        params.append(end_iso)
+    where = ("WHERE " + " AND ".join(clauses)) if clauses else ""
+    params.append(limit)
+    return list(_get_conn().execute(
+        f"SELECT * FROM {table} {where} ORDER BY {ts_col} DESC LIMIT ?",
+        params,
+    ).fetchall())
+
+
+def audit_in_range(start_iso: Optional[str], end_iso: Optional[str],
+                   limit: int = 500) -> list[sqlite3.Row]:
+    return _range_filter_rows("audit_log", "timestamp", start_iso, end_iso, limit)
+
+
+def errors_in_range(start_iso: Optional[str], end_iso: Optional[str],
+                    limit: int = 500) -> list[sqlite3.Row]:
+    return _range_filter_rows("errors", "timestamp", start_iso, end_iso, limit)
+
+
 # ---------------------------------------------------------------------------
 # Retention cleanup
 # ---------------------------------------------------------------------------
@@ -845,13 +898,13 @@ def partnership_accept(request_id: int, user_id: int) -> bool:
     if get_accepted_partnership(row["from_user_id"]) or get_accepted_partnership(user_id):
         return False
     partner_id = row["from_user_id"]
-    with _lock:
+    with _lock, _tx() as c:
-        _get_conn().execute(
+        c.execute(
             "UPDATE partnerships SET status = 'accepted', accepted_at = ? WHERE id = ?",
             (now_iso(), request_id),
         )
         # clean up any stale pending requests touching either user
-        _get_conn().execute(
+        c.execute(
             """DELETE FROM partnerships
                 WHERE status = 'pending'
                   AND (from_user_id IN (?, ?) OR to_user_id IN (?, ?))""",
@@ -899,12 +952,12 @@ def partner_flat_actions(partner_id: int) -> dict:
 def cleanup_retention() -> dict:
     cutoff = (datetime.now(timezone.utc) - timedelta(days=RETENTION_DAYS)).isoformat(timespec="seconds")
     stats = {}
-    with _lock:
+    with _lock, _tx() as c:
         for table in ("errors", "audit_log"):
-            cur = _get_conn().execute(f"DELETE FROM {table} WHERE timestamp < ?", (cutoff,))
+            cur = c.execute(f"DELETE FROM {table} WHERE timestamp < ?", (cutoff,))
             stats[table] = cur.rowcount
         # Drop forensics from old applications (but keep the row itself for history)
-        cur = _get_conn().execute(
+        cur = c.execute(
             "UPDATE applications SET forensics_json = NULL WHERE started_at < ? AND forensics_json IS NOT NULL",
             (cutoff,),
         )

web/enrichment.py

@@ -218,8 +218,20 @@ def _record_failure(flat_id: str, step: str, reason: str) -> None:
         pass
 
 
+# Holding strong references to every spawned task so asyncio doesn't GC them
+# mid-flight. create_task only weakly references tasks from the event loop.
+_bg_tasks: set[asyncio.Task] = set()
+
+
+def _spawn(coro) -> asyncio.Task:
+    t = asyncio.create_task(coro)
+    _bg_tasks.add(t)
+    t.add_done_callback(_bg_tasks.discard)
+    return t
+
+
 def kick(flat_id: str) -> None:
-    asyncio.create_task(asyncio.to_thread(enrich_flat_sync, flat_id))
+    _spawn(asyncio.to_thread(enrich_flat_sync, flat_id))
 
 
 async def _backfill_runner() -> None:
@@ -234,5 +246,5 @@ async def _backfill_runner() -> None:
 
 def kick_backfill() -> int:
     pending = db.flats_needing_enrichment(limit=200)
-    asyncio.create_task(_backfill_runner())
+    _spawn(_backfill_runner())
     return len(pending)

web/notifications.py

@@ -84,8 +84,8 @@ def on_apply_ok(user_id: int, flat: dict, message: str) -> None:
 
 def on_apply_fail(user_id: int, flat: dict, message: str) -> None:
     addr = flat.get("address") or flat.get("link")
-    body = f"Bewerbung fehlgeschlagen: {addr}\n{message}\n{PUBLIC_URL}/fehler"
+    body = f"Bewerbung fehlgeschlagen: {addr}\n{message}\n{PUBLIC_URL}/bewerbungen"
     md = (f"*Bewerbung fehlgeschlagen*\n{addr}\n{message}\n"
-          f"[Fehler ansehen]({PUBLIC_URL}/fehler)")
+          f"[Bewerbungen ansehen]({PUBLIC_URL}/bewerbungen)")
     notify_user(user_id, "apply_fail", subject="[wohnungsdidi] Bewerbung fehlgeschlagen",
                 body_plain=body, body_markdown=md)