tradein-mvp/backend/app/services/estimator.py

@@ -26,7 +26,7 @@ import logging
 import math
 import re
 import time
-from datetime import UTC, datetime, timedelta
+from datetime import UTC, date, datetime, timedelta
 from typing import Any
 from uuid import uuid4
 
@@ -78,6 +78,15 @@ MIN_ANALOGS_PER_SOURCE = 5  # гарантированный минимум на
 LISTINGS_FRESH_DAYS = 14  # объявления не старше 14 дней
 DEALS_PERIOD_MONTHS = 12  # сделки за последний год
 
+# #794: СберИндекс time-adjustment of frozen Rosreestr ДКП deals.
+# Rosreestr deals freeze ~2026-01; the sber monthly index re-bases a stale deal's ppm²
+# to the latest available month. Region fixed to Свердловская обл. (tradein MVP = ЕКБ).
+SBER_TIME_ADJUST_REGION = "Свердловская область"
+# Coefficient series preference: hedonic (quality-adjusted, cleanest) → deals (fallback).
+SBER_COEFF_DASHBOARDS = ("residential_real_estate_prices", "real_estate_deals")
+SBER_TIME_FACTOR_MIN = 0.7  # clamp guards against bad/sparse index months
+SBER_TIME_FACTOR_MAX = 1.6
+
 # #699: санитизация ДКП-выбросов (Росреестр `deals`). В сырых сделках встречаются
 # нерыночные/битые записи — доли, сделки с обременением, опечатки этажа/площади —
 # которые шумят actual_deals (display) и dkp_corridor/expected_sold. Абсолютные
@@ -934,6 +943,60 @@ def _apply_quarter_index(
     return adjusted_ppm2, adjusted_median_price, adjusted_range_low, adjusted_range_high, factor
 
 
+def _load_sber_index_series(db: Session, *, region: str) -> dict[date, float]:
+    """#794: monthly {period_month: index_value} for region from sber_price_index.
+
+    Tries SBER_COEFF_DASHBOARDS in order; returns first non-empty series. {} on any error.
+    """
+    for dash in SBER_COEFF_DASHBOARDS:
+        try:
+            rows = (
+                db.execute(
+                    text("""
+                        SELECT period_month, index_value_rub_m2
+                        FROM sber_price_index
+                        WHERE city = CAST(:region AS text)
+                          AND dashboard = CAST(:dash AS text)
+                        ORDER BY period_month
+                    """),
+                    {"region": region, "dash": dash},
+                )
+                .mappings()
+                .all()
+            )
+        except Exception as exc:
+            logger.warning("sber_price_index lookup failed for %s (graceful): %s", dash, exc)
+            continue
+        if rows:
+            return {r["period_month"]: float(r["index_value_rub_m2"]) for r in rows}
+    return {}
+
+
+def _sber_time_factor(series: dict[date, float], deal_month: date) -> float:
+    """#794: factor = idx[latest] / idx[deal_month], clamped. 1.0 when no data / recent deal.
+
+    series: {first-of-month date -> index value}. deal_month: first-of-month of the deal.
+    If deal_month absent, use the nearest available month <= deal_month; if none, nearest overall.
+    If deal_month >= latest available month -> 1.0 (no extrapolation of recent deals).
+    """
+    if not series:
+        return 1.0
+    latest = max(series)
+    if deal_month >= latest:
+        return 1.0
+    base = series.get(deal_month)
+    if base is None:
+        earlier = [m for m in series if m <= deal_month]
+        if earlier:
+            base = series[max(earlier)]
+        else:
+            base = series[min(series)]  # deal older than series start → use earliest
+    if not base or base <= 0:
+        return 1.0
+    factor = series[latest] / base
+    return max(SBER_TIME_FACTOR_MIN, min(SBER_TIME_FACTOR_MAX, factor))
+
+
 def _fetch_dkp_corridor(
     db: Session,
     *,
@@ -963,7 +1026,7 @@ def _fetch_dkp_corridor(
             db.execute(
                 text(
                     """
-                    SELECT price_per_m2
+                    SELECT price_per_m2, deal_date
                     FROM deals
                     WHERE source = 'rosreestr'
                       AND address ILIKE :street_pattern
@@ -995,9 +1058,33 @@ def _fetch_dkp_corridor(
         logger.warning("dkp_corridor lookup failed (graceful): %s", exc)
         return None
 
-    ppm2_values = sorted(float(r["price_per_m2"]) for r in rows if r["price_per_m2"])
+    # #794: apply СберИндекс time-adjustment to re-base stale Rosreestr ДКП ppm²
+    # to the latest available index month. Graceful: factor=1.0 when table is empty.
+    series = _load_sber_index_series(db, region=SBER_TIME_ADJUST_REGION)
+    adjusted: list[float] = []
+    factors_applied: list[float] = []
+    for r in rows:
+        ppm2 = r["price_per_m2"]
+        if not ppm2:
+            continue
+        dd = r.get("deal_date")
+        factor = 1.0
+        if series and dd is not None:
+            deal_month = date(dd.year, dd.month, 1)
+            factor = _sber_time_factor(series, deal_month)
+        adjusted.append(float(ppm2) * factor)
+        factors_applied.append(factor)
+    ppm2_values = sorted(adjusted)
     if not ppm2_values:
         return None
+    if series and factors_applied:
+        logger.info(
+            "dkp_corridor #794 time-adjust: n=%d factor min=%.3f max=%.3f region=%s",
+            len(factors_applied),
+            min(factors_applied),
+            max(factors_applied),
+            SBER_TIME_ADJUST_REGION,
+        )
     return {
         "count": len(ppm2_values),
         "low_ppm2": int(ppm2_values[0]),

tradein-mvp/backend/app/services/sber_index.py

@@ -1,4 +1,4 @@
-"""СберИндекс city-level secondary-housing price index pull (#887).
+"""СберИндекс city-level secondary-housing price index pull (#887 + #794).
 
 Fetches monthly time-series data from sberindex.ru/api/sowa (reverse-engineered
 in vault research note 2026-05-31-0845-resolver-794) across three dashboards:
@@ -10,19 +10,15 @@ API summary:
   POST https://sberindex.ru/api/sowa
   Body: {"SOWA": {"method": "GET", "route": "<base64>", "data": {"type": "object", "value": []}}}
   route = base64( /dataset/v1/<dashboard>?filter=<urlencode(json)>&limit=1000&offset=0 )
-  filter = {"REF_AREA": "<code>", "FREQ": "M", "SOURCE": "SI", "REALTY": "2"}
+  filter = per-dashboard (see SBER_DASHBOARDS below); common keys: REF_AREA + FREQ:M
   Required headers: content-type, rquid (random 32-hex), x-language, user-agent.
 
-Response fields (each cell is __string__<b64> or __number__<raw>):
-  indicator_id, kpi_id, period, value, obs_status, source, ref_area, realty,
-  freq, unit_measure, unit_mult
+Response cells: __string__<b64> or __number__<raw>. Field names read from 'fields' entry.
 
-Data-quality benchmark: after upsert of the dinamika-tsen-obyavlenii (asking) series,
-the latest asking index per city is logged at INFO level as a data-quality reference.
-Full asking-vs-our-median reconciliation is a separate follow-up (#887 step 5+).
-
-NOTE — estimator time-adjust wire (step 4) is OUT OF SCOPE for this PR.
-It is a client-visible change that requires a backtest gate. Defer to a separate issue.
+#794 fix: build_sber_route was hardcoding SOURCE:SI + REALTY:2 for ALL dashboards.
+Live-verified 2026-05-31: residential_real_estate_prices needs REAL_ESTATE_NOVELTY,
+dinamika-tsen-obyavlenii needs SOURCE:DK + PRICE_TYPE. Filter is now per-dashboard via
+SberDashboard dataclass.
 
 REF_AREA codes (sberindex internal region IDs, not ОКАТО/ISO):
   643 = Россия               — confirmed live, vault research note 2026-05-31-0845.
@@ -41,6 +37,7 @@ import json
 import logging
 import uuid
 from collections.abc import AsyncIterator
+from dataclasses import dataclass
 from datetime import UTC, date, datetime
 from urllib.parse import quote
 
@@ -63,11 +60,37 @@ SBER_REF_AREAS: dict[str, str] = {
     "77": "Москва",
 }
 
-# Dashboards to pull: slug → human label (used as 'segment' placeholder)
-SBER_DASHBOARDS: list[str] = [
-    "real_estate_deals",
-    "residential_real_estate_prices",
-    "dinamika-tsen-obyavlenii",
+
+# ---------------------------------------------------------------------------
+# Per-dashboard config (#794 fix — each dashboard needs different filter params)
+# ---------------------------------------------------------------------------
+
+
+@dataclass(frozen=True)
+class SberDashboard:
+    slug: str
+    extra_filter: dict[str, str]  # beyond REF_AREA + FREQ:"M" — verified live 2026-05-31
+    segment_field: str  # response field carrying the segment label
+
+
+# All three series are the secondary-market (вторичка) ряд;
+# one segment per dashboard keeps the (city,period_month,dashboard) PK valid.
+SBER_DASHBOARDS: list[SberDashboard] = [
+    SberDashboard(
+        "real_estate_deals",
+        {"SOURCE": "SI", "REALTY": "2"},
+        "realty",
+    ),
+    SberDashboard(
+        "residential_real_estate_prices",
+        {"SOURCE": "SI", "REAL_ESTATE_TYPE": "1", "REAL_ESTATE_NOVELTY": "3"},
+        "real_estate_novelty",
+    ),
+    SberDashboard(
+        "dinamika-tsen-obyavlenii",
+        {"SOURCE": "DK", "PRICE_TYPE": "1"},
+        "price_type",
+    ),
 ]
 
 SBER_API_URL = "https://sberindex.ru/api/sowa"
@@ -83,20 +106,16 @@ _CHROME_UA = (
 # ---------------------------------------------------------------------------
 
 
-def build_sber_route(dashboard: str, ref_area: str) -> str:
+def build_sber_route(dashboard: str, ref_area: str, extra_filter: dict[str, str]) -> str:
     """Build the base64-encoded route for the /api/sowa payload.
 
     Encodes /dataset/v1/<dashboard>?filter=<urlencode(json)>&limit=1000&offset=0
-    where filter = {"REF_AREA": ref_area, "FREQ": "M", "SOURCE": "SI", "REALTY": "2"}.
+    where filter = {"REF_AREA": ref_area, "FREQ": "M", **extra_filter}.
 
+    extra_filter is per-dashboard (see SberDashboard.extra_filter); verified live 2026-05-31.
     All filter values are strings per the live-captured payload (vault research note).
     """
-    filter_dict = {
-        "REF_AREA": str(ref_area),
-        "FREQ": "M",
-        "SOURCE": "SI",
-        "REALTY": "2",
-    }
+    filter_dict = {"REF_AREA": str(ref_area), "FREQ": "M", **extra_filter}
     # urlencode the JSON, then build the path
     filter_str = quote(json.dumps(filter_dict, separators=(",", ":")), safe="")
     path = f"/dataset/v1/{dashboard}?filter={filter_str}&limit=1000&offset=0"
@@ -107,21 +126,6 @@ def build_sber_route(dashboard: str, ref_area: str) -> str:
 # Response decoder
 # ---------------------------------------------------------------------------
 
-# Field order returned by the API (confirmed from live session)
-_FIELD_ORDER = [
-    "indicator_id",
-    "kpi_id",
-    "period",
-    "value",
-    "obs_status",
-    "source",
-    "ref_area",
-    "realty",
-    "freq",
-    "unit_measure",
-    "unit_mult",
-]
-
 
 def _decode_cell(cell: str) -> str | float:
     """Decode a single response cell.
@@ -212,19 +216,20 @@ def _parse_period_month(period_str: str) -> date:
 async def fetch_sber_index(
     client: httpx.AsyncClient,
     *,
-    dashboard: str,
+    dashboard: SberDashboard,
     ref_area: str,
 ) -> AsyncIterator[tuple[str, date, str, str, float]]:
     """Fetch one dashboard × REF_AREA combination from sberindex.ru/api/sowa.
 
     Yields tuples of:
-        (city_label, period_month, segment_label, dashboard, index_value_rub_m2)
+        (city_label, period_month, segment_label, dashboard_slug, index_value_rub_m2)
 
-    city_label and segment_label come from the API response fields 'ref_area' and 'realty'.
+    city_label comes from the API response field 'ref_area'.
+    segment_label comes from dashboard.segment_field (per-dashboard, verified 2026-05-31).
 
     Raises httpx.HTTPStatusError on non-2xx response (caller handles per-series).
     """
-    route = build_sber_route(dashboard, ref_area)
+    route = build_sber_route(dashboard.slug, ref_area, dashboard.extra_filter)
     rquid = uuid.uuid4().hex  # 32-hex random, required header
 
     payload = {
@@ -251,7 +256,7 @@ async def fetch_sber_index(
         period_raw = row.get("period", "")
         value_raw = row.get("value")
         city_label = str(row.get("ref_area", ref_area))
-        segment_label = str(row.get("realty", ""))
+        segment_label = str(row.get(dashboard.segment_field, ""))
 
         if not period_raw or value_raw is None:
             continue
@@ -262,13 +267,13 @@ async def fetch_sber_index(
         except (ValueError, TypeError) as exc:
             logger.warning(
                 "sber_index: skip row — parse error for dashboard=%s ref_area=%s: %s",
-                dashboard,
+                dashboard.slug,
                 ref_area,
                 exc,
             )
             continue
 
-        yield (city_label, period_month, segment_label, dashboard, index_value)
+        yield (city_label, period_month, segment_label, dashboard.slug, index_value)
 
 
 # ---------------------------------------------------------------------------
@@ -280,20 +285,20 @@ async def pull_sber_indices(
     db: Session,
     *,
     cities: dict[str, str] | None = None,
-    dashboards: list[str] | None = None,
+    dashboards: list[SberDashboard] | None = None,
 ) -> dict[str, int]:
     """Fetch all configured dashboards × cities and upsert into sber_price_index.
 
     Args:
         db: SQLAlchemy Session (tradein DB).
         cities: REF_AREA code → city label mapping. Defaults to SBER_REF_AREAS.
-        dashboards: list of dashboard slugs to pull. Defaults to SBER_DASHBOARDS.
+        dashboards: list of SberDashboard configs to pull. Defaults to SBER_DASHBOARDS.
 
     Returns dict of counters: {upserted: int, skipped: int, errors: int}.
 
     Per-series try/except: one failing series logs + continues (does not abort others).
     After upserting 'dinamika-tsen-obyavlenii', logs the latest asking index per city
-    as a data-quality benchmark reference.
+    as a data-quality benchmark reference and compares to our scrape-median asking ppm².
     """
     if cities is None:
         cities = SBER_REF_AREAS
@@ -315,7 +320,7 @@ async def pull_sber_indices(
                     if not rows_to_upsert:
                         logger.info(
                             "sber_index: no rows returned for dashboard=%s ref_area=%s",
-                            dashboard,
+                            dashboard.slug,
                             ref_area,
                         )
                         counters["skipped"] += 1
@@ -359,35 +364,64 @@ async def pull_sber_indices(
                     logger.info(
                         "sber_index: upserted %d rows for dashboard=%s ref_area=%s",
                         len(rows_to_upsert),
-                        dashboard,
+                        dashboard.slug,
                         ref_area,
                     )
 
                     # Data-quality benchmark log for asking-price series
-                    if dashboard == "dinamika-tsen-obyavlenii" and rows_to_upsert:
+                    if dashboard.slug == "dinamika-tsen-obyavlenii" and rows_to_upsert:
                         latest_row = max(rows_to_upsert, key=lambda r: r[1])
                         city_lbl, latest_month, _, _, latest_val = latest_row
                         logger.info(
                             "sber_index benchmark [asking]: city=%r latest_month=%s "
                             "index_value_rub_m2=%.0f "
-                            "(data-quality ref; full asking-vs-our-median is follow-up)",
+                            "(data-quality ref; full asking-vs-our-median below)",
                             city_lbl,
                             latest_month.isoformat(),
                             latest_val,
                         )
+                        # our listings median is ЕКБ-only →
+                        # compare only against Свердловская обл. (REF_AREA 66)
+                        if ref_area == "66":
+                            # Task B: best-effort reconciliation to our scrape-median asking ppm²
+                            try:
+                                our_median = db.execute(
+                                    text("""
+                                        SELECT percentile_cont(0.5)
+                                            WITHIN GROUP (ORDER BY price_per_m2) AS m
+                                        FROM listings
+                                        WHERE is_active = true
+                                          AND price_per_m2 BETWEEN 50000 AND 800000
+                                    """)
+                                ).scalar()
+                                if our_median is not None and latest_val:
+                                    sber_latest = latest_val
+                                    divergence_pct = (our_median - sber_latest) / sber_latest * 100
+                                    logger.info(
+                                        "sber_index benchmark [asking vs our median]: "
+                                        "sber=%.0f our_median=%.0f divergence=%+.1f%% "
+                                        "(data-quality signal)",
+                                        sber_latest,
+                                        our_median,
+                                        divergence_pct,
+                                    )
+                            except Exception as exc:
+                                logger.debug(
+                                    "sber benchmark reconciliation skipped (graceful): %s", exc
+                                )
 
                 except httpx.HTTPStatusError as exc:
                     logger.error(
                         "sber_index: HTTP %d for dashboard=%s ref_area=%s — skip series",
                         exc.response.status_code,
-                        dashboard,
+                        dashboard.slug,
                         ref_area,
                     )
                     counters["errors"] += 1
                 except httpx.RequestError as exc:
                     logger.error(
                         "sber_index: network error for dashboard=%s ref_area=%s: %s — skip",
-                        dashboard,
+                        dashboard.slug,
                         ref_area,
                         exc,
                     )
@@ -395,7 +429,7 @@ async def pull_sber_indices(
                 except Exception:
                     logger.exception(
                         "sber_index: unexpected error for dashboard=%s ref_area=%s — skip",
-                        dashboard,
+                        dashboard.slug,
                         ref_area,
                     )
                     counters["errors"] += 1

tradein-mvp/backend/tests/fixtures/sber_real_estate_deals_66.json

@@ -0,0 +1,130 @@
+{
+  "SOWA": {
+    "method": "GET",
+    "route": "L2RhdGFzZXQvdjEvcmVhbF9lc3RhdGVfZGVhbHM/ZmlsdGVyPSU3QiUyMlJFRl9BUkVBJTIyJTNBJTIyNjYlMjIlMkMlMjJGUkVRJTIyJTNBJTIyTSUyMiUyQyUyMlNPVVJDRSUyMiUzQSUyMlNJJTIyJTJDJTIyUkVBTFRZJTIyJTNBJTIyMiUyMiU3RCZsaW1pdD00Jm9mZnNldD0w",
+    "data": {
+      "type": "object",
+      "value": [
+        {
+          "key": "fields",
+          "type": "object",
+          "value": [
+            "__string__aW5kaWNhdG9yX2lk",
+            "__string__a3BpX2lk",
+            "__string__cGVyaW9k",
+            "__string__dmFsdWU=",
+            "__string__b2JzX3N0YXR1cw==",
+            "__string__c291cmNl",
+            "__string__cmVmX2FyZWE=",
+            "__string__cmVhbHR5",
+            "__string__ZnJlcQ==",
+            "__string__dW5pdF9tZWFzdXJl",
+            "__string__dW5pdF9tdWx0"
+          ]
+        },
+        {
+          "key": "data",
+          "type": "object",
+          "value": [
+            [
+              "__string__ODM0NTUxNTktMjYyOC00ZmNlLWIzNDktZGZjODU3MTU1ZjEx",
+              "__string__NjQzMDMyMDAx",
+              "__string__MjAxNy0wMS0zMFQyMTowMDowMC4wMDBa",
+              "__number__51046",
+              "__string__QQ==",
+              "__string__0JTQsNC90L3Ri9C1INCh0LHQtdGA0JjQvdC00LXQutGB0LA=",
+              "__string__0KHQstC10YDQtNC70L7QstGB0LrQsNGPINC+0LHQu9Cw0YHRgtGM",
+              "__string__0JLRgtC+0YDQuNGH0L3Ri9C5",
+              "__string__0JzQtdGB0Y/Rhg==",
+              "__string__0YDRg9Cx",
+              "__string__MA=="
+            ],
+            [
+              "__string__ODM0NTUxNTktMjYyOC00ZmNlLWIzNDktZGZjODU3MTU1ZjEx",
+              "__string__NjQzMDMyMDAx",
+              "__string__MjAxNy0wMi0yN1QyMTowMDowMC4wMDBa",
+              "__number__50762",
+              "__string__QQ==",
+              "__string__0JTQsNC90L3Ri9C1INCh0LHQtdGA0JjQvdC00LXQutGB0LA=",
+              "__string__0KHQstC10YDQtNC70L7QstGB0LrQsNGPINC+0LHQu9Cw0YHRgtGM",
+              "__string__0JLRgtC+0YDQuNGH0L3Ri9C5",
+              "__string__0JzQtdGB0Y/Rhg==",
+              "__string__0YDRg9Cx",
+              "__string__MA=="
+            ],
+            [
+              "__string__ODM0NTUxNTktMjYyOC00ZmNlLWIzNDktZGZjODU3MTU1ZjEx",
+              "__string__NjQzMDMyMDAx",
+              "__string__MjAxNy0wMy0zMFQyMTowMDowMC4wMDBa",
+              "__number__50902",
+              "__string__QQ==",
+              "__string__0JTQsNC90L3Ri9C1INCh0LHQtdGA0JjQvdC00LXQutGB0LA=",
+              "__string__0KHQstC10YDQtNC70L7QstGB0LrQsNGPINC+0LHQu9Cw0YHRgtGM",
+              "__string__0JLRgtC+0YDQuNGH0L3Ri9C5",
+              "__string__0JzQtdGB0Y/Rhg==",
+              "__string__0YDRg9Cx",
+              "__string__MA=="
+            ],
+            [
+              "__string__ODM0NTUxNTktMjYyOC00ZmNlLWIzNDktZGZjODU3MTU1ZjEx",
+              "__string__NjQzMDMyMDAx",
+              "__string__MjAxNy0wNC0yOVQyMTowMDowMC4wMDBa",
+              "__number__50958",
+              "__string__QQ==",
+              "__string__0JTQsNC90L3Ri9C1INCh0LHQtdGA0JjQvdC00LXQutGB0LA=",
+              "__string__0KHQstC10YDQtNC70L7QstGB0LrQsNGPINC+0LHQu9Cw0YHRgtGM",
+              "__string__0JLRgtC+0YDQuNGH0L3Ri9C5",
+              "__string__0JzQtdGB0Y/Rhg==",
+              "__string__0YDRg9Cx",
+              "__string__MA=="
+            ]
+          ]
+        },
+        {
+          "key": "pagination",
+          "type": "object",
+          "value": {
+            "type": "object",
+            "value": [
+              {
+                "key": "total_records",
+                "type": "number",
+                "value": "__number__112"
+              },
+              {
+                "key": "current_page",
+                "type": "number",
+                "value": "__number__1"
+              },
+              {
+                "key": "total_pages",
+                "type": "number",
+                "value": "__number__28"
+              },
+              {
+                "key": "next_page",
+                "type": "number",
+                "value": "__number__2"
+              },
+              {
+                "key": "prev_page",
+                "type": "null",
+                "value": "__null__null"
+              }
+            ]
+          }
+        },
+        {
+          "key": "limit",
+          "type": "number",
+          "value": "__number__4"
+        },
+        {
+          "key": "offset",
+          "type": "number",
+          "value": "__number__0"
+        }
+      ]
+    }
+  }
+}

tradein-mvp/backend/tests/services/test_estimator_sber_time_adjust.py

@@ -0,0 +1,80 @@
+"""Tests for #794 СберИндекс time-adjustment helper — pure, no DB."""
+
+from __future__ import annotations
+
+import os
+import sys
+from datetime import date
+from unittest.mock import MagicMock
+
+# DATABASE_URL required by pydantic Settings before any app import.
+os.environ.setdefault("DATABASE_URL", "postgresql+psycopg://test:test@localhost:5432/test")
+
+# WeasyPrint stub — not installed in CI без GTK.
+sys.modules.setdefault("weasyprint", MagicMock())
+
+from app.services.estimator import (  # noqa: E402
+    SBER_TIME_FACTOR_MAX,
+    SBER_TIME_FACTOR_MIN,
+    _sber_time_factor,
+)
+
+
+def test_empty_series_returns_one() -> None:
+    assert _sber_time_factor({}, date(2026, 1, 1)) == 1.0
+
+
+def test_deal_month_equals_latest_returns_one() -> None:
+    series = {date(2026, 1, 1): 95_000.0, date(2026, 4, 1): 100_000.0}
+    assert _sber_time_factor(series, date(2026, 4, 1)) == 1.0
+
+
+def test_deal_month_after_latest_returns_one() -> None:
+    series = {date(2026, 1, 1): 95_000.0, date(2026, 4, 1): 100_000.0}
+    assert _sber_time_factor(series, date(2026, 6, 1)) == 1.0
+
+
+def test_normal_factor_calculation() -> None:
+    series = {date(2026, 1, 1): 95_000.0, date(2026, 4, 1): 100_000.0}
+    factor = _sber_time_factor(series, date(2026, 1, 1))
+    expected = 100_000.0 / 95_000.0  # ≈ 1.0526
+    assert abs(factor - expected) < 0.0001
+    assert SBER_TIME_FACTOR_MIN <= factor <= SBER_TIME_FACTOR_MAX
+
+
+def test_clamp_high() -> None:
+    """Very old deal → factor would be >>1.6 → clamp to SBER_TIME_FACTOR_MAX."""
+    series = {date(2020, 1, 1): 10_000.0, date(2026, 4, 1): 100_000.0}
+    factor = _sber_time_factor(series, date(2020, 1, 1))
+    assert factor == SBER_TIME_FACTOR_MAX
+
+
+def test_clamp_low() -> None:
+    """Series shows price drop → factor <<0.7 → clamp to SBER_TIME_FACTOR_MIN."""
+    series = {date(2020, 1, 1): 200_000.0, date(2026, 4, 1): 50_000.0}
+    factor = _sber_time_factor(series, date(2020, 1, 1))
+    assert factor == SBER_TIME_FACTOR_MIN
+
+
+def test_missing_month_uses_nearest_earlier() -> None:
+    """deal_month=2026-02 not in series; nearest earlier is 2026-01."""
+    series = {date(2026, 1, 1): 95_000.0, date(2026, 4, 1): 100_000.0}
+    # Using 2026-01 as base: factor = 100000/95000
+    factor_with_missing = _sber_time_factor(series, date(2026, 2, 1))
+    factor_explicit = _sber_time_factor(series, date(2026, 1, 1))
+    assert abs(factor_with_missing - factor_explicit) < 0.0001
+
+
+def test_deal_older_than_series_uses_earliest() -> None:
+    """Deal month before all series data → use earliest available month."""
+    series = {date(2023, 1, 1): 80_000.0, date(2026, 4, 1): 100_000.0}
+    # deal at 2020-01 is before series start → base = series[2023-01] = 80000
+    factor = _sber_time_factor(series, date(2020, 1, 1))
+    expected = min(100_000.0 / 80_000.0, SBER_TIME_FACTOR_MAX)
+    assert abs(factor - expected) < 0.0001
+
+
+def test_zero_base_returns_one() -> None:
+    """Zero index value in series → guard → return 1.0."""
+    series = {date(2026, 1, 1): 0.0, date(2026, 4, 1): 100_000.0}
+    assert _sber_time_factor(series, date(2026, 1, 1)) == 1.0

tradein-mvp/backend/tests/services/test_sber_index.py

@@ -0,0 +1,113 @@
+"""Tests for app/services/sber_index.py — per-dashboard filter fix (#794)."""
+
+from __future__ import annotations
+
+import base64
+import json
+from datetime import date
+from pathlib import Path
+from urllib.parse import unquote
+
+import pytest
+
+from app.services.sber_index import (
+    SBER_DASHBOARDS,
+    SberDashboard,
+    _parse_period_month,
+    build_sber_route,
+    decode_sber_response,
+)
+
+# ---------------------------------------------------------------------------
+# Fixture path
+# ---------------------------------------------------------------------------
+
+FIXTURE_PATH = Path(__file__).parent.parent / "fixtures" / "sber_real_estate_deals_66.json"
+
+
+# ---------------------------------------------------------------------------
+# test_build_sber_route_per_dashboard
+# LOCKS the bug fix: each dashboard must have the correct filter keys.
+# ---------------------------------------------------------------------------
+
+
+@pytest.mark.parametrize("dashboard", SBER_DASHBOARDS)
+def test_build_sber_route_per_dashboard(dashboard: SberDashboard) -> None:
+    route_b64 = build_sber_route(dashboard.slug, "66", dashboard.extra_filter)
+    path = base64.b64decode(route_b64).decode("utf-8")
+
+    # Extract the filter JSON from the path: ?filter=<urlencoded>&limit=...
+    filter_part = path.split("filter=")[1].split("&")[0]
+    filter_dict = json.loads(unquote(filter_part))
+
+    # All routes must have REF_AREA + FREQ=M
+    assert filter_dict.get("REF_AREA") == "66"
+    assert filter_dict.get("FREQ") == "M"
+
+    if dashboard.slug == "real_estate_deals":
+        assert filter_dict.get("SOURCE") == "SI"
+        assert filter_dict.get("REALTY") == "2"
+
+    elif dashboard.slug == "residential_real_estate_prices":
+        assert filter_dict.get("SOURCE") == "SI"
+        assert filter_dict.get("REAL_ESTATE_NOVELTY") == "3"
+
+    elif dashboard.slug == "dinamika-tsen-obyavlenii":
+        assert filter_dict.get("SOURCE") == "DK"
+        assert filter_dict.get("PRICE_TYPE") == "1"
+
+    else:
+        pytest.fail(f"Unknown dashboard slug: {dashboard.slug!r}")
+
+
+# ---------------------------------------------------------------------------
+# test_decode_sber_response_real_fixture
+# ---------------------------------------------------------------------------
+
+
+def test_decode_sber_response_real_fixture() -> None:
+    with FIXTURE_PATH.open(encoding="utf-8") as f:
+        raw = json.load(f)
+
+    rows = decode_sber_response(raw)
+
+    assert len(rows) >= 1, "Expected at least 1 decoded row from real fixture"
+
+    # All rows should have the expected fields present
+    first = rows[0]
+    assert "ref_area" in first
+    assert "realty" in first
+    assert "value" in first
+    assert "period" in first
+
+    # Values must be typed correctly
+    assert isinstance(first["value"], float)
+    assert isinstance(first["period"], str) and first["period"]
+
+    # Verify region label decoded correctly
+    regions = {r["ref_area"] for r in rows}
+    assert (
+        "Свердловская область" in regions
+    ), f"Expected 'Свердловская область' in ref_area values, got: {regions}"
+
+    # Verify secondary-market segment present
+    realty_vals = {r["realty"] for r in rows}
+    assert any(
+        "тори" in str(v) or "Вторичн" in str(v) for v in realty_vals
+    ), f"Expected secondary-market label in realty field, got: {realty_vals}"
+
+
+# ---------------------------------------------------------------------------
+# test_parse_period_month
+# ---------------------------------------------------------------------------
+
+
+def test_parse_period_month() -> None:
+    result = _parse_period_month("2026-04-29T21:00:00.000Z")
+    assert result == date(2026, 4, 1)
+
+
+def test_parse_period_month_z_suffix() -> None:
+    """Original format from live API."""
+    result = _parse_period_month("2017-01-30T21:00:00Z")
+    assert result == date(2017, 1, 1)