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+# Modul-04-Market-Regime — Betriebsdokumentation
+
+> Erstellt: 20.08.2026 (Rain Ocampo) · Status: ✅ Freigegeben (E2E bestanden)
+
+## Zweck
+Erster **Consumer** der Market-Data-Events von Modul-03. Pipeline:
+`MARKET_DATA_READY / MARKET_CANDLE_CLOSED (Modul-03) → Regime-Berechnung → PostgreSQL (market_regime) → MARKET_REGIME_READY`
+**Deterministische, regelbasierte Engine — bewusst OHNE KI/ML.**
+
+## Container
+| Attribut | Wert |
+|----------|------|
+| Name | `Modul-04-Market-Regime` |
+| Image | `market-regime:1.0.0` (lokal gebaut) |
+| Port | **55004** — **NUR intern** (`expose`, nicht öffentlich) |
+| Netzwerk | `trading-modules` (bridge) |
+| Build-Context | `/opt/trading-modules/modul04-market-regime/` |
+| Restart | `unless-stopped` |
+| Healthcheck | ✅ `healthy` |
+
+## Deployment
+```bash
+cd /opt/trading-modules
+docker compose build modul-04-market-regime
+docker compose up -d --no-deps --force-recreate modul-04-market-regime
+```
+
+## Environment Variables (Compose)
+| Variable | Wert (Default) | Zweck |
+|----------|---------------|-------|
+| `PG_HOST` | `Modul-01-PostgreSQL` | Docker-interner Servicename |
+| `PG_PORT` | `5432` | intern (Host: 55432) |
+| `PG_USER/PASSWORD/DB` | `trading` | aus `.env`-Defaults |
+| `RABBITMQ_HOST` | `Modul-02-RabbitMQ` | Docker-interner Servicename |
+| `RABBITMQ_PORT` | `5672` | intern (Host: 55672) |
+| `RABBITMQ_USER/PASSWORD/VHOST` | `trading` | **vhost `trading`** |
+| `LOG_LEVEL` | `INFO` | Strukturiertes Logging |
+
+Keine festen IPs — nur Docker-interne Hostnamen. Creds via Compose env + Defaults.
+
+## Architektur
+```
+Modul-03 ──market.data.ready / market.data.candle.closed──▶ RegimeConsumer
+                                                            │  (bindet beide Routing-Keys)
+                                                            ▼
+                                              RegimeEngine (deterministisch)
+                                              EMA / ADX / ATR / Slope / Preisstruktur
+                                                            │
+                                                ┌───────────┴───────────┐
+                                                ▼                       ▼
+                                       market_regime (PG)      MARKET_REGIME_READY
+                                       (16 Spalten)            → market.regime.ready
+```
+
+- **Consumer** (`app/consumer/consumer.py`): bindet `market.data.ready` + `market.data.candle.closed`; durable Queue `market-regime.input`; manuelles Ack; Reconnect mit Backoff; **schließt alte Verbindung beim Reconnect** (verhindert Consumer-Leak/Nachrichtenverlust).
+- **Engine** (`app/regime/engine.py`): deterministisch, ohne KI.
+- **Storage** (`app/storage/storage.py`): idempotent via partiellen Unique-Index.
+- **Publisher** (`app/publisher/publisher.py`): publiziert `MARKET_REGIME_READY` auf `market.regime` (Routing `market.regime.ready`).
+- **History-Client** (`app/marketdata/client.py`): liest OHLCV über interne FastAPI Modul-03 (`http://Modul-03-Market-Data:55003/history/{symbol}`).
+
+## Regime-Engine (`app/regime/engine.py`)
+Deterministische Regel-Engine (Version `1.0.0`), 7 Regime:
+`TREND_UP, TREND_DOWN, RANGE, HIGH_VOLATILITY, LOW_VOLATILITY, TRANSITION, UNKNOWN`
+
+**Indikatoren & Metriken:**
+| Indikator | Fenster/Param | Zweck |
+|-----------|---------------|-------|
+| EMA fast/slow | 10 / 30 | Trendrichtung (EMA-Flanken-Differenz) |
+| ADX | 14 | Trendstärke (≥20 = echter Trend) |
+| ATR | 14 | Volatilität (absolut + Ratio + Perzentil) |
+| Slope | 20 | normierte Steigung der Close-Linie |
+| Preisstruktur | — | higher_highs / lower_lows / range |
+
+**Zentrale Schwellenwerte** (`app/config.py`, env-overridable):
+| Parameter | Default | Bedeutung |
+|-----------|---------|-----------|
+| `min_candles_required` | 30 | UNKNOWN, wenn weniger Daten |
+| `regime_lookback` | 60 | max. Kerzen für Berechnung |
+| `trend_min_ema_gap` | 0.02 | |EMA_fast-EMA_slow|/close ≥ → Trend |
+| `adx_trend_threshold` | 20.0 | ADX ≥ → echter Trend |
+| `slope_up/down_threshold` | 0.05 / -0.05 | normierte Steigung |
+| `range_atr_ratio` | 0.02 | ATR/close darunter = Range |
+| `atr_high_vol_multiplier` | 1.5 | ATR jetzt > hist_mean × → HIGH_VOL |
+| `atr_low_vol_multiplier` | 0.6 | ATR jetzt < hist_mean × → LOW_VOL |
+| `high_vol_atr_ratio` | 0.03 | ATR/close ≥ → starke Vol |
+| `low_vol_atr_ratio` | 0.008 | ATR/close ≤ → geringe Vol |
+| `slope_threshold` | 0.01 | |Slope| darunter = seitwärts |
+| `transition_min_events` | 3 | Events für TRANSITION |
+
+## Datenbank (Modul-01-PostgreSQL)
+Tabelle `public.market_regime` (16 Spalten, eigene Tabelle — bestehende unangetastet):
+```sql
+symbol TEXT, asset_class TEXT, timeframe TEXT, provider TEXT,
+regime TEXT, confidence INTEGER (0-100),
+trend_strength DOUBLE PRECISION, volatility_state TEXT,
+timestamp TIMESTAMPTZ, indicators_json JSONB,
+candles_used INTEGER, version TEXT,
+source_event_id TEXT, correlation_id TEXT,
+data_ts TIMESTAMPTZ, data_ts_end TIMESTAMPTZ
+```
+- **Unique (partiell):** `uq_market_regime_src` auf `(symbol, timeframe, source_event_id)` **WHERE source_event_id IS NOT NULL** → Idempotenz.
+- Migration: `migrations/001_market_regime.sql` (idempotent, löscht nichts).
+
+## RabbitMQ (Modul-02)
+| Exchange | Typ | Routing | Event |
+|----------|-----|---------|-------|
+| `market.data` | topic | `market.data.ready` (eingang) | MARKET_DATA_READY |
+| `market.data` | topic | `market.data.candle.closed` (eingang) | MARKET_CANDLE_CLOSED |
+| `market.regime` | topic | `market.regime.ready` (**ausgang**) | MARKET_REGIME_READY |
+
+## Interne API
+| Endpoint | Zweck |
+|----------|-------|
+| `GET /health` | Liveness (200 immer) + Komponentenstatus im Body |
+| `GET /health/ready` | Readiness (503 wenn PG/RabbitMQ/Modul-03 down) |
+| `GET /regime/{symbol}` | Regime-Einträge abfragen |
+| `GET /regime/latest/{symbol}` | Letztes Regime eines Symbols |
+
+## End-to-End-Test (20.08.2026, final, nach Rebuild) ✅
+Kette verifiziert: Modul-03 Ingest → `market.data.ready` → Modul-04 Consumer → RegimeEngine → `market_regime` → `MARKET_REGIME_READY` auf `market.regime.ready`.
+
+| Fall | Regime | Conf | candles | version | Event | DB |
+|------|--------|------|---------|---------|-------|----|
+| M4TREND_UP (40) | TREND_UP | 100 | 40 | 1.0.0 | genau 1 | ✅ |
+| M4TREND_DN (40) | TREND_DOWN | 100 | 40 | 1.0.0 | genau 1 | ✅ |
+| M4RANGE (40) | LOW_VOLATILITY (Range) | 60 | 40 | 1.0.0 | genau 1 | ✅ |
+| M4HIGHVOL (40) | HIGH_VOLATILITY | 75 | 40 | 1.0.0 | genau 1 | ✅ |
+| M4UNKNOWN (5) | UNKNOWN | 20 | 5 | 1.0.0 | genau 1 | ✅ |
+| M4IDEMPOT (40) | TREND_UP | 100 | 40 | 1.0.0 | genau 1 | ✅ |
+
+**Idempotenz:** dasselbe Quell-Event (`source_event_id`) erneut → **kein zweiter Datensatz**, kein Doppel-Event. ✅
+**Logs:** keine Errors/Tracebacks. Health `{postgresql:true, rabbitmq:true, market_data_ready:true}`. ✅
+
+## Bugs behoben während E2E (20.08.2026)
+| Bug | Fix |
+|-----|-----|
+| `can't adapt type 'dict'` (JSONB) | `json.dumps(ind.model_dump(mode="json"))` |
+| `tuple index out of range` (16/15) | `version` in INSERT-VALUES ergänzt |
+| `ON CONFLICT` + partieller Index Fehler | `WHERE source_event_id IS NOT NULL` in Klausel |
+| `model_dump(default=...)` TypeError | `default`-Kwarg entfernt (`model_dump(mode="json")`) |
+| Consumer-Verbindungs-Leak | `conn.close()` bei Reconnect → kein Message-Leak |
+
+## Offene Punkte
+- Consumer-Downstream für `market.regime.ready` (Modul-05+)
+- Bestätigte TRANSITION-Detektion mit echten Folgedaten
+
+---
+```
+Geändert von: Rain Ocampo
+Datum: 20.08.2026
+Grund: Modul-04-Dokumentation angelegt (Regime-Engine, market_regime-Schema, Events, E2E freigegeben).
+```