Files
orion/app/services/stock_service.py

571 lines
20 KiB
Python

# app/services/stock_service.py
"""
Stock service for managing inventory operations.
This module provides classes and functions for:
- Stock quantity management (set, add, remove)
- Stock information retrieval and validation
- Location-based inventory tracking
- GTIN normalization and validation
"""
import logging
from datetime import datetime, timezone
from typing import List, Optional
from sqlalchemy.orm import Session
from app.exceptions import (
StockNotFoundException,
InsufficientStockException,
InvalidStockOperationException,
StockValidationException,
NegativeStockException,
InvalidQuantityException,
ValidationException,
)
from models.schemas.stock import (StockAdd, StockCreate, StockLocationResponse,
StockSummaryResponse, StockUpdate)
from models.database.product import Product
from models.database.stock import Stock
from app.utils.data_processing import GTINProcessor
logger = logging.getLogger(__name__)
class StockService:
"""Service class for stock operations following the application's service pattern."""
def __init__(self):
"""Class constructor."""
self.gtin_processor = GTINProcessor()
def set_stock(self, db: Session, stock_data: StockCreate) -> Stock:
"""
Set exact stock quantity for a GTIN at a specific location (replaces existing quantity).
Args:
db: Database session
stock_data: Stock creation data
Returns:
Stock object with updated quantity
Raises:
InvalidQuantityException: If quantity is negative
StockValidationException: If GTIN or location is invalid
"""
try:
# Validate and normalize input
normalized_gtin = self._validate_and_normalize_gtin(stock_data.gtin)
location = self._validate_and_normalize_location(stock_data.location)
self._validate_quantity(stock_data.quantity, allow_zero=True)
# Check if stock entry already exists for this GTIN and location
existing_stock = self._get_stock_entry(db, normalized_gtin, location)
if existing_stock:
# Update existing stock (SET to exact quantity)
old_quantity = existing_stock.quantity
existing_stock.quantity = stock_data.quantity
existing_stock.updated_at = datetime.now(timezone.utc)
db.commit()
db.refresh(existing_stock)
logger.info(
f"Updated stock for GTIN {normalized_gtin} at {location}: {old_quantity}{stock_data.quantity}"
)
return existing_stock
else:
# Create new stock entry
new_stock = Stock(
gtin=normalized_gtin,
location=location,
quantity=stock_data.quantity
)
db.add(new_stock)
db.commit()
db.refresh(new_stock)
logger.info(
f"Created new stock for GTIN {normalized_gtin} at {location}: {stock_data.quantity}"
)
return new_stock
except (InvalidQuantityException, StockValidationException):
db.rollback()
raise # Re-raise custom exceptions
except Exception as e:
db.rollback()
logger.error(f"Error setting stock: {str(e)}")
raise ValidationException("Failed to set stock")
def add_stock(self, db: Session, stock_data: StockAdd) -> Stock:
"""
Add quantity to existing stock for a GTIN at a specific location (adds to existing quantity).
Args:
db: Database session
stock_data: Stock addition data
Returns:
Stock object with updated quantity
Raises:
InvalidQuantityException: If quantity is not positive
StockValidationException: If GTIN or location is invalid
"""
try:
# Validate and normalize input
normalized_gtin = self._validate_and_normalize_gtin(stock_data.gtin)
location = self._validate_and_normalize_location(stock_data.location)
self._validate_quantity(stock_data.quantity, allow_zero=False)
# Check if stock entry already exists for this GTIN and location
existing_stock = self._get_stock_entry(db, normalized_gtin, location)
if existing_stock:
# Add to existing stock
old_quantity = existing_stock.quantity
existing_stock.quantity += stock_data.quantity
existing_stock.updated_at = datetime.now(timezone.utc)
db.commit()
db.refresh(existing_stock)
logger.info(
f"Added stock for GTIN {normalized_gtin} at {location}: "
f"{old_quantity} + {stock_data.quantity} = {existing_stock.quantity}"
)
return existing_stock
else:
# Create new stock entry with the quantity
new_stock = Stock(
gtin=normalized_gtin,
location=location,
quantity=stock_data.quantity
)
db.add(new_stock)
db.commit()
db.refresh(new_stock)
logger.info(
f"Created new stock for GTIN {normalized_gtin} at {location}: {stock_data.quantity}"
)
return new_stock
except (InvalidQuantityException, StockValidationException):
db.rollback()
raise # Re-raise custom exceptions
except Exception as e:
db.rollback()
logger.error(f"Error adding stock: {str(e)}")
raise ValidationException("Failed to add stock")
def remove_stock(self, db: Session, stock_data: StockAdd) -> Stock:
"""
Remove quantity from existing stock for a GTIN at a specific location.
Args:
db: Database session
stock_data: Stock removal data
Returns:
Stock object with updated quantity
Raises:
StockNotFoundException: If no stock found for GTIN/location
InsufficientStockException: If not enough stock available
InvalidQuantityException: If quantity is not positive
NegativeStockException: If operation would result in negative stock
"""
try:
# Validate and normalize input
normalized_gtin = self._validate_and_normalize_gtin(stock_data.gtin)
location = self._validate_and_normalize_location(stock_data.location)
self._validate_quantity(stock_data.quantity, allow_zero=False)
# Find existing stock entry
existing_stock = self._get_stock_entry(db, normalized_gtin, location)
if not existing_stock:
raise StockNotFoundException(normalized_gtin, identifier_type="gtin")
# Check if we have enough stock to remove
if existing_stock.quantity < stock_data.quantity:
raise InsufficientStockException(
gtin=normalized_gtin,
location=location,
requested=stock_data.quantity,
available=existing_stock.quantity
)
# Remove from existing stock
old_quantity = existing_stock.quantity
new_quantity = existing_stock.quantity - stock_data.quantity
# Validate resulting quantity
if new_quantity < 0:
raise NegativeStockException(normalized_gtin, location, new_quantity)
existing_stock.quantity = new_quantity
existing_stock.updated_at = datetime.now(timezone.utc)
db.commit()
db.refresh(existing_stock)
logger.info(
f"Removed stock for GTIN {normalized_gtin} at {location}: "
f"{old_quantity} - {stock_data.quantity} = {existing_stock.quantity}"
)
return existing_stock
except (StockValidationException, StockNotFoundException, InsufficientStockException, InvalidQuantityException,
NegativeStockException):
db.rollback()
raise # Re-raise custom exceptions
except Exception as e:
db.rollback()
logger.error(f"Error removing stock: {str(e)}")
raise ValidationException("Failed to remove stock")
def get_stock_by_gtin(self, db: Session, gtin: str) -> StockSummaryResponse:
"""
Get all stock locations and total quantity for a specific GTIN.
Args:
db: Database session
gtin: GTIN to look up
Returns:
StockSummaryResponse with locations and totals
Raises:
StockNotFoundException: If no stock found for GTIN
StockValidationException: If GTIN is invalid
"""
try:
normalized_gtin = self._validate_and_normalize_gtin(gtin)
# Get all stock entries for this GTIN
stock_entries = db.query(Stock).filter(Stock.gtin == normalized_gtin).all()
if not stock_entries:
raise StockNotFoundException(normalized_gtin, identifier_type="gtin")
# Calculate total quantity and build locations list
total_quantity = 0
locations = []
for entry in stock_entries:
total_quantity += entry.quantity
locations.append(
StockLocationResponse(location=entry.location, quantity=entry.quantity)
)
# Try to get product title for reference
product = db.query(Product).filter(Product.gtin == normalized_gtin).first()
product_title = product.title if product else None
return StockSummaryResponse(
gtin=normalized_gtin,
total_quantity=total_quantity,
locations=locations,
product_title=product_title,
)
except (StockNotFoundException, StockValidationException):
raise # Re-raise custom exceptions
except Exception as e:
logger.error(f"Error getting stock by GTIN {gtin}: {str(e)}")
raise ValidationException("Failed to retrieve stock information")
def get_total_stock(self, db: Session, gtin: str) -> dict:
"""
Get total quantity in stock for a specific GTIN.
Args:
db: Database session
gtin: GTIN to look up
Returns:
Dictionary with total stock information
Raises:
StockNotFoundException: If no stock found for GTIN
StockValidationException: If GTIN is invalid
"""
try:
normalized_gtin = self._validate_and_normalize_gtin(gtin)
# Calculate total stock
total_stock = db.query(Stock).filter(Stock.gtin == normalized_gtin).all()
if not total_stock:
raise StockNotFoundException(normalized_gtin, identifier_type="gtin")
total_quantity = sum(entry.quantity for entry in total_stock)
# Get product info for context
product = db.query(Product).filter(Product.gtin == normalized_gtin).first()
return {
"gtin": normalized_gtin,
"total_quantity": total_quantity,
"product_title": product.title if product else None,
"locations_count": len(total_stock),
}
except (StockNotFoundException, StockValidationException):
raise # Re-raise custom exceptions
except Exception as e:
logger.error(f"Error getting total stock for GTIN {gtin}: {str(e)}")
raise ValidationException("Failed to retrieve total stock")
def get_all_stock(
self,
db: Session,
skip: int = 0,
limit: int = 100,
location: Optional[str] = None,
gtin: Optional[str] = None,
) -> List[Stock]:
"""
Get all stock entries with optional filtering.
Args:
db: Database session
skip: Number of records to skip
limit: Maximum records to return
location: Optional location filter
gtin: Optional GTIN filter
Returns:
List of Stock objects
"""
try:
query = db.query(Stock)
if location:
query = query.filter(Stock.location.ilike(f"%{location}%"))
if gtin:
normalized_gtin = self._normalize_gtin(gtin)
if normalized_gtin:
query = query.filter(Stock.gtin == normalized_gtin)
return query.offset(skip).limit(limit).all()
except Exception as e:
logger.error(f"Error getting all stock: {str(e)}")
raise ValidationException("Failed to retrieve stock entries")
def update_stock(
self, db: Session, stock_id: int, stock_update: StockUpdate
) -> Stock:
"""
Update stock quantity for a specific stock entry.
Args:
db: Database session
stock_id: Stock entry ID
stock_update: Update data
Returns:
Updated Stock object
Raises:
StockNotFoundException: If stock entry not found
InvalidQuantityException: If quantity is invalid
"""
try:
stock_entry = self._get_stock_by_id_or_raise(db, stock_id)
# Validate new quantity
self._validate_quantity(stock_update.quantity, allow_zero=True)
stock_entry.quantity = stock_update.quantity
stock_entry.updated_at = datetime.now(timezone.utc)
db.commit()
db.refresh(stock_entry)
logger.info(
f"Updated stock entry {stock_id} to quantity {stock_update.quantity}"
)
return stock_entry
except (StockNotFoundException, InvalidQuantityException):
db.rollback()
raise # Re-raise custom exceptions
except Exception as e:
db.rollback()
logger.error(f"Error updating stock {stock_id}: {str(e)}")
raise ValidationException("Failed to update stock")
def delete_stock(self, db: Session, stock_id: int) -> bool:
"""
Delete a stock entry.
Args:
db: Database session
stock_id: Stock entry ID
Returns:
True if deletion successful
Raises:
StockNotFoundException: If stock entry not found
"""
try:
stock_entry = self._get_stock_by_id_or_raise(db, stock_id)
gtin = stock_entry.gtin
location = stock_entry.location
db.delete(stock_entry)
db.commit()
logger.info(f"Deleted stock entry {stock_id} for GTIN {gtin} at {location}")
return True
except StockNotFoundException:
raise # Re-raise custom exceptions
except Exception as e:
db.rollback()
logger.error(f"Error deleting stock {stock_id}: {str(e)}")
raise ValidationException("Failed to delete stock entry")
def get_stock_summary_by_location(self, db: Session, location: str) -> dict:
"""
Get stock summary for a specific location.
Args:
db: Database session
location: Location to summarize
Returns:
Dictionary with location stock summary
"""
try:
normalized_location = self._validate_and_normalize_location(location)
stock_entries = db.query(Stock).filter(Stock.location == normalized_location).all()
if not stock_entries:
return {
"location": normalized_location,
"total_items": 0,
"total_quantity": 0,
"unique_gtins": 0,
}
total_quantity = sum(entry.quantity for entry in stock_entries)
unique_gtins = len(set(entry.gtin for entry in stock_entries))
return {
"location": normalized_location,
"total_items": len(stock_entries),
"total_quantity": total_quantity,
"unique_gtins": unique_gtins,
}
except StockValidationException:
raise # Re-raise custom exceptions
except Exception as e:
logger.error(f"Error getting stock summary for location {location}: {str(e)}")
raise ValidationException("Failed to retrieve location stock summary")
def get_low_stock_items(self, db: Session, threshold: int = 10) -> List[dict]:
"""
Get items with stock below threshold.
Args:
db: Database session
threshold: Stock threshold to consider "low"
Returns:
List of low stock items with details
"""
try:
if threshold < 0:
raise InvalidQuantityException(threshold, "Threshold must be non-negative")
low_stock_entries = db.query(Stock).filter(Stock.quantity <= threshold).all()
low_stock_items = []
for entry in low_stock_entries:
# Get product info if available
product = db.query(Product).filter(Product.gtin == entry.gtin).first()
low_stock_items.append({
"gtin": entry.gtin,
"location": entry.location,
"current_quantity": entry.quantity,
"product_title": product.title if product else None,
"product_id": product.product_id if product else None,
})
return low_stock_items
except InvalidQuantityException:
raise # Re-raise custom exceptions
except Exception as e:
logger.error(f"Error getting low stock items: {str(e)}")
raise ValidationException("Failed to retrieve low stock items")
# Private helper methods
def _validate_and_normalize_gtin(self, gtin: str) -> str:
"""Validate and normalize GTIN format."""
if not gtin or not gtin.strip():
raise StockValidationException("GTIN is required", field="gtin")
normalized_gtin = self._normalize_gtin(gtin)
if not normalized_gtin:
raise StockValidationException("Invalid GTIN format", field="gtin")
return normalized_gtin
def _validate_and_normalize_location(self, location: str) -> str:
"""Validate and normalize location."""
if not location or not location.strip():
raise StockValidationException("Location is required", field="location")
return location.strip().upper()
def _validate_quantity(self, quantity: int, allow_zero: bool = True) -> None:
"""Validate quantity value."""
if quantity is None:
raise InvalidQuantityException(quantity, "Quantity is required")
if not isinstance(quantity, int):
raise InvalidQuantityException(quantity, "Quantity must be an integer")
if quantity < 0:
raise InvalidQuantityException(quantity, "Quantity cannot be negative")
if not allow_zero and quantity == 0:
raise InvalidQuantityException(quantity, "Quantity must be positive")
def _normalize_gtin(self, gtin_value) -> Optional[str]:
"""Normalize GTIN format using the GTINProcessor."""
try:
return self.gtin_processor.normalize(gtin_value)
except Exception as e:
logger.error(f"Error normalizing GTIN {gtin_value}: {str(e)}")
return None
def _get_stock_entry(self, db: Session, gtin: str, location: str) -> Optional[Stock]:
"""Get stock entry by GTIN and location."""
return (
db.query(Stock)
.filter(Stock.gtin == gtin, Stock.location == location)
.first()
)
def _get_stock_by_id_or_raise(self, db: Session, stock_id: int) -> Stock:
"""Get stock by ID or raise exception."""
stock_entry = db.query(Stock).filter(Stock.id == stock_id).first()
if not stock_entry:
raise StockNotFoundException(str(stock_id))
return stock_entry
# Create service instance
stock_service = StockService()