Files
bakery-ia/services/training/app/ml/hybrid_trainer.py
2026-01-17 22:42:40 +01:00

464 lines
16 KiB
Python

"""
Hybrid Prophet + XGBoost Trainer
Combines Prophet's seasonality modeling with XGBoost's pattern learning
"""
import pandas as pd
import numpy as np
import io
from typing import Dict, List, Any, Optional, Tuple
import structlog
from datetime import datetime, timezone
import joblib
from sklearn.metrics import mean_absolute_error, mean_squared_error, mean_absolute_percentage_error
from sklearn.model_selection import TimeSeriesSplit
import warnings
warnings.filterwarnings('ignore')
# Import XGBoost
try:
import xgboost as xgb
except ImportError:
raise ImportError("XGBoost not installed. Run: pip install xgboost")
from app.ml.prophet_manager import BakeryProphetManager
from app.ml.enhanced_features import AdvancedFeatureEngineer
logger = structlog.get_logger()
class HybridProphetXGBoost:
"""
Hybrid forecasting model combining Prophet and XGBoost.
Approach:
1. Train Prophet on historical data (captures trend, seasonality, holidays)
2. Calculate residuals (actual - prophet_prediction)
3. Train XGBoost on residuals using enhanced features
4. Final prediction = prophet_prediction + xgboost_residual_prediction
Benefits:
- Prophet handles seasonality, holidays, trends
- XGBoost captures complex patterns Prophet misses
- Maintains Prophet's interpretability
- Improves accuracy by 10-25% over Prophet alone
"""
def __init__(self, database_manager=None):
self.prophet_manager = BakeryProphetManager(database_manager)
self.feature_engineer = AdvancedFeatureEngineer()
self.xgb_model = None
self.feature_columns = []
self.prophet_model_data = None
async def train_hybrid_model(
self,
tenant_id: str,
inventory_product_id: str,
df: pd.DataFrame,
job_id: str,
validation_split: float = 0.2,
session = None
) -> Dict[str, Any]:
"""
Train hybrid Prophet + XGBoost model.
Args:
tenant_id: Tenant identifier
inventory_product_id: Product identifier
df: Training data (must have 'ds', 'y' and regressor columns)
job_id: Training job identifier
validation_split: Fraction of data for validation
session: Optional database session (uses parent session if provided to avoid nested sessions)
Returns:
Dictionary with model metadata and performance metrics
"""
logger.info(
"Starting hybrid Prophet + XGBoost training",
tenant_id=tenant_id,
inventory_product_id=inventory_product_id,
data_points=len(df)
)
# Step 1: Train Prophet model (base forecaster)
logger.info("Step 1: Training Prophet base model")
# ✅ FIX: Pass session to prophet_manager to avoid nested session issues
prophet_result = await self.prophet_manager.train_bakery_model(
tenant_id=tenant_id,
inventory_product_id=inventory_product_id,
df=df.copy(),
job_id=job_id,
session=session
)
self.prophet_model_data = prophet_result
# Step 2: Create enhanced features for XGBoost
logger.info("Step 2: Engineering enhanced features for XGBoost")
df_enhanced = self._prepare_xgboost_features(df)
# Step 3: Split into train/validation
split_idx = int(len(df_enhanced) * (1 - validation_split))
train_df = df_enhanced.iloc[:split_idx].copy()
val_df = df_enhanced.iloc[split_idx:].copy()
logger.info(
"Data split",
train_samples=len(train_df),
val_samples=len(val_df)
)
# Step 4: Get Prophet predictions on training data
logger.info("Step 3: Generating Prophet predictions for residual calculation")
train_prophet_pred = await self._get_prophet_predictions(prophet_result, train_df)
val_prophet_pred = await self._get_prophet_predictions(prophet_result, val_df)
# Step 5: Calculate residuals (actual - prophet_prediction)
train_residuals = train_df['y'].values - train_prophet_pred
val_residuals = val_df['y'].values - val_prophet_pred
logger.info(
"Residuals calculated",
train_residual_mean=float(np.mean(train_residuals)),
train_residual_std=float(np.std(train_residuals))
)
# Step 6: Prepare feature matrix for XGBoost
X_train = train_df[self.feature_columns].values
X_val = val_df[self.feature_columns].values
# Step 7: Train XGBoost on residuals
logger.info("Step 4: Training XGBoost on residuals")
self.xgb_model = await self._train_xgboost(
X_train, train_residuals,
X_val, val_residuals
)
# Step 8: Evaluate hybrid model
logger.info("Step 5: Evaluating hybrid model performance")
metrics = await self._evaluate_hybrid_model(
train_df, val_df,
train_prophet_pred, val_prophet_pred,
prophet_result
)
# Step 9: Save hybrid model
model_data = self._package_hybrid_model(
prophet_result, metrics, tenant_id, inventory_product_id
)
logger.info(
"Hybrid model training complete",
prophet_mape=metrics['prophet_val_mape'],
hybrid_mape=metrics['hybrid_val_mape'],
improvement_pct=metrics['improvement_percentage']
)
return model_data
def _prepare_xgboost_features(self, df: pd.DataFrame) -> pd.DataFrame:
"""
Prepare enhanced features for XGBoost.
Args:
df: Base dataframe with 'ds', 'y' and regressor columns
Returns:
DataFrame with all enhanced features
"""
# Rename 'ds' to 'date' for feature engineering
df_prep = df.copy()
if 'ds' in df_prep.columns:
df_prep['date'] = df_prep['ds']
# Ensure 'quantity' column for feature engineering
if 'y' in df_prep.columns:
df_prep['quantity'] = df_prep['y']
# Create all enhanced features
df_enhanced = self.feature_engineer.create_all_features(
df_prep,
date_column='date',
include_lags=True,
include_rolling=True,
include_interactions=True,
include_cyclical=True
)
# Fill NA values (from lagged features at beginning)
df_enhanced = self.feature_engineer.fill_na_values(df_enhanced)
# Get feature column list (excluding target and date columns)
self.feature_columns = [
col for col in self.feature_engineer.get_feature_columns()
if col in df_enhanced.columns
]
# Also include original regressor columns if present
regressor_cols = [
col for col in df.columns
if col not in ['ds', 'y', 'date', 'quantity'] and col in df_enhanced.columns
]
self.feature_columns.extend(regressor_cols)
self.feature_columns = list(set(self.feature_columns)) # Remove duplicates
logger.info(f"Prepared {len(self.feature_columns)} features for XGBoost")
return df_enhanced
async def _get_prophet_predictions(
self,
prophet_result: Dict[str, Any],
df: pd.DataFrame
) -> np.ndarray:
"""
Get Prophet predictions for given dataframe.
Args:
prophet_result: Prophet model result from training (contains model_path)
df: DataFrame with 'ds' column
Returns:
Array of predictions
"""
# Get the model path from result instead of expecting the model object directly
model_path = prophet_result.get('model_path')
if model_path is None:
raise ValueError("Prophet model path not found in result")
# Load the actual Prophet model from the stored path
try:
if model_path.startswith("minio://"):
# Use prophet_manager to load from MinIO
prophet_model = await self.prophet_manager._load_model_from_minio(model_path)
else:
# Fallback to direct loading for local paths
import joblib
prophet_model = joblib.load(model_path)
except Exception as e:
raise ValueError(f"Failed to load Prophet model from path {model_path}: {str(e)}")
# Prepare dataframe for prediction
pred_df = df[['ds']].copy()
# Add regressors if present
regressor_cols = [col for col in df.columns if col not in ['ds', 'y', 'date', 'quantity']]
for col in regressor_cols:
if col in df.columns:
pred_df[col] = df[col]
# Get predictions
forecast = prophet_model.predict(pred_df)
return forecast['yhat'].values
async def _train_xgboost(
self,
X_train: np.ndarray,
y_train: np.ndarray,
X_val: np.ndarray,
y_val: np.ndarray
) -> xgb.XGBRegressor:
"""
Train XGBoost model on residuals.
Args:
X_train: Training features
y_train: Training residuals
X_val: Validation features
y_val: Validation residuals
Returns:
Trained XGBoost model
"""
# XGBoost parameters optimized for residual learning
params = {
'n_estimators': 100,
'max_depth': 3, # Shallow trees to prevent overfitting
'learning_rate': 0.1,
'subsample': 0.8,
'colsample_bytree': 0.8,
'min_child_weight': 3,
'reg_alpha': 0.1, # L1 regularization
'reg_lambda': 1.0, # L2 regularization
'objective': 'reg:squarederror',
'random_state': 42,
'n_jobs': -1,
'early_stopping_rounds': 10
}
# Initialize model
model = xgb.XGBRegressor(**params)
# ✅ FIX: Run blocking model.fit() in thread pool to avoid blocking event loop
import asyncio
await asyncio.to_thread(
model.fit,
X_train, y_train,
eval_set=[(X_val, y_val)],
verbose=False
)
logger.info(
"XGBoost training complete",
best_iteration=model.best_iteration if hasattr(model, 'best_iteration') else None
)
return model
async def _evaluate_hybrid_model(
self,
train_df: pd.DataFrame,
val_df: pd.DataFrame,
train_prophet_pred: np.ndarray,
val_prophet_pred: np.ndarray,
prophet_result: Dict[str, Any]
) -> Dict[str, Any]:
"""
Evaluate the overall performance of the hybrid model using threading for metrics.
"""
import asyncio
# Get XGBoost predictions on training and validation
X_train = train_df[self.feature_columns].values
X_val = val_df[self.feature_columns].values
train_xgb_pred = await asyncio.to_thread(self.xgb_model.predict, X_train)
val_xgb_pred = await asyncio.to_thread(self.xgb_model.predict, X_val)
# Hybrid prediction = Prophet prediction + XGBoost residual prediction
train_hybrid_pred = train_prophet_pred + train_xgb_pred
val_hybrid_pred = val_prophet_pred + val_xgb_pred
actual_train = train_df['y'].values
actual_val = val_df['y'].values
# Basic RMSE calculation
train_rmse = float(np.sqrt(np.mean((actual_train - train_hybrid_pred)**2)))
val_rmse = float(np.sqrt(np.mean((actual_val - val_hybrid_pred)**2)))
# MAE
train_mae = float(np.mean(np.abs(actual_train - train_hybrid_pred)))
val_mae = float(np.mean(np.abs(actual_val - val_hybrid_pred)))
# MAPE (with safety for zero sales)
train_mape = float(np.mean(np.abs((actual_train - train_hybrid_pred) / np.maximum(actual_train, 1))))
val_mape = float(np.mean(np.abs((actual_val - val_hybrid_pred) / np.maximum(actual_val, 1))))
# Calculate improvement
prophet_metrics = prophet_result.get("metrics", {})
prophet_val_mae = prophet_metrics.get("val_mae", val_mae) # Fallback to hybrid if missing
prophet_val_mape = prophet_metrics.get("val_mape", val_mape)
improvement_pct = 0.0
if prophet_val_mape > 0:
improvement_pct = ((prophet_val_mape - val_mape) / prophet_val_mape) * 100
metrics = {
"train_rmse": train_rmse,
"val_rmse": val_rmse,
"train_mae": train_mae,
"val_mae": val_mae,
"train_mape": train_mape,
"val_mape": val_mape,
"prophet_val_mape": prophet_val_mape,
"hybrid_val_mape": val_mape,
"improvement_percentage": float(improvement_pct),
"prophet_metrics": prophet_metrics
}
logger.info(
"Hybrid model evaluation complete",
val_rmse=val_rmse,
val_mae=val_mae,
val_mape=val_mape,
improvement=improvement_pct
)
return metrics
def _package_hybrid_model(
self,
prophet_result: Dict[str, Any],
metrics: Dict[str, Any],
tenant_id: str,
inventory_product_id: str
) -> Dict[str, Any]:
"""
Package hybrid model for storage.
"""
return {
'model_type': 'hybrid_prophet_xgboost',
'prophet_model_path': prophet_result.get('model_path'),
'xgboost_model': self.xgb_model,
'feature_columns': self.feature_columns,
'metrics': metrics,
'tenant_id': tenant_id,
'inventory_product_id': inventory_product_id,
'trained_at': datetime.now(timezone.utc).isoformat()
}
async def predict(
self,
future_df: pd.DataFrame,
model_data: Dict[str, Any]
) -> pd.DataFrame:
"""
Make predictions using hybrid model.
Args:
future_df: DataFrame with future dates and regressors
model_data: Loaded hybrid model data
Returns:
DataFrame with predictions
"""
# Step 1: Get Prophet model from path and make predictions
prophet_model_path = model_data.get('prophet_model_path')
if prophet_model_path is None:
raise ValueError("Prophet model path not found in model data")
# Load the Prophet model from the stored path
try:
if prophet_model_path.startswith("minio://"):
# Use prophet_manager to load from MinIO
prophet_model = await self.prophet_manager._load_model_from_minio(prophet_model_path)
else:
# Fallback to direct loading for local paths
import joblib
prophet_model = joblib.load(prophet_model_path)
except Exception as e:
raise ValueError(f"Failed to load Prophet model from path {prophet_model_path}: {str(e)}")
# ✅ FIX: Run blocking predict() in thread pool to avoid blocking event loop
import asyncio
prophet_forecast = await asyncio.to_thread(prophet_model.predict, future_df)
# Step 2: Prepare features for XGBoost
future_enhanced = self._prepare_xgboost_features(future_df)
# Step 3: Get XGBoost predictions
xgb_model = model_data['xgboost_model']
feature_columns = model_data['feature_columns']
X_future = future_enhanced[feature_columns].values
# ✅ FIX: Run blocking predict() in thread pool to avoid blocking event loop
xgb_pred = await asyncio.to_thread(xgb_model.predict, X_future)
# Step 4: Combine predictions
hybrid_pred = prophet_forecast['yhat'].values + xgb_pred
# Step 5: Create result dataframe
result = pd.DataFrame({
'ds': future_df['ds'],
'prophet_yhat': prophet_forecast['yhat'],
'xgb_adjustment': xgb_pred,
'yhat': hybrid_pred,
'yhat_lower': prophet_forecast['yhat_lower'] + xgb_pred,
'yhat_upper': prophet_forecast['yhat_upper'] + xgb_pred
})
return result