Stock Lot Documentation¶

Overview¶

The Stock Lot module (stock.lot) manages lot numbers, serial numbers, and batch tracking for inventory items. It enables traceability, expiry management, quality control, and detailed tracking of individual units or batches throughout the supply chain.

Model Information¶

Model Name: stock.lot
Display Name: Lot / Serial Number
Key Fields: number

Features¶

✅ Audit logging enabled
❌ Multi-company support (not enforced)
❌ Auto-sync disabled
✅ Unique key constraint on number

Lot Tracking Types¶

Type	Code	Description
Product	`product`	Standard product batches (default)
Asset	`asset`	Fixed asset tracking
Sample	`sample`	Laboratory samples

Lot States¶

State	Description
`active`	Lot is active and available for use
`inactive`	Lot is deactivated (excluded from balance calculations)

Key Fields Reference¶

Header Fields¶

Field	Type	Required	Description
`number`	Char	✅	Unique lot/serial number
`lot_tracking_type`	Selection	❌	Product/Asset/Sample (default: product)
`product_id`	Many2One	❌	Associated product
`state`	Selection	❌	active/inactive
`description`	Text	❌	Lot description

Date Fields¶

Field	Type	Description
`received_date`	DateTime	When lot was received
`mfg_date`	Date	Manufacturing date
`expiry_date`	Date	Expiration date
`life_75_date`	Date	75% shelf life date (computed)
`life_50_date`	Date	50% shelf life date (computed)
`life_remain_percent`	Decimal	Remaining shelf life % (computed)

Physical Properties¶

Field	Type	Description
`weight`	Decimal	Weight (kg)
`net_weight`	Decimal	Net weight (kg)
`gross_weight`	Decimal	Gross weight (kg)
`width`	Decimal	Width dimension
`length`	Decimal	Length dimension
`thickness`	Decimal	Thickness dimension
`diameter`	Decimal	Diameter dimension
`area_m2`	Decimal	Area in square meters
`temperature`	Decimal	Storage temperature

Tracking Fields¶

Field	Type	Description
`supp_lot_no`	Char	Supplier's lot number
`po_number`	Many2One	Purchase order reference
`project_id`	Many2One	Associated project
`url`	Char	External URL/link
`ratio`	Char	Conversion ratio

Quality Control Fields¶

Field	Type	Description
`defect_categ`	Many2One	Defect category
`grade`	Text	Quality grade
`test_description`	Char	Test description
`notes_and_comments`	Char	Additional notes

Equipment/Asset Fields (for asset tracking)¶

Field	Type	Description
`asset_id`	Many2One	Fixed asset reference
`machine_number`	Many2One	Machine number
`last_calibration_date`	Date	Last calibration
`next_calibration_date`	Date	Next calibration due
`last_maintenance`	Date	Last maintenance
`next_maintenance`	Date	Next maintenance due
`equipment_status`	Selection	active/under_maintenance/out_of_service

Relationship Fields¶

Field	Type	Description
`comments`	One2Many	Discussion thread
`stock_balances`	One2Many	Current stock quantities by location
`moves`	One2Many	All stock transactions
`expiry_moves`	One2Many	Expiry-related movements
`lot_items`	One2Many	Sub-items in lot
`lot_lines`	One2Many	Lot line details
`validate_lines`	One2Many	Validation records

Computed Fields¶

Field	Type	Description
`last_location_id`	Many2One	Last known location
`lot_items_summary`	Char	Summary of lot items
`total_weight`	Decimal	Total weight from lot lines
`total_pcs`	Decimal	Total pieces from lot lines

API Methods¶

1. Create Lot¶

Method: create(vals, context)

Creates a new lot number.

Context Options:

context = {
    "sequence_name": "LOT-BATCH"  # Specific sequence to use
}

Example:

# Auto-generated lot number
lot_id = get_model("stock.lot").create({
    "product_id": 100,
    "mfg_date": "2025-10-01",
    "expiry_date": "2026-10-01",
    "weight": 50.5,
    "description": "Batch A from supplier XYZ"
}, context={"sequence_name": "stock_lot"})

# Manual lot number
manual_lot = get_model("stock.lot").create({
    "number": "LOT-2025-001",
    "product_id": 100,
    "lot_tracking_type": "product"
})

2. Update Expired Lots¶

Method: update_expired_lots(context)

Automatically processes expired lots and moves them to expiry location.

Behavior: - Runs as scheduled task - Finds lots past expiry_date - Creates stock movements to expiry location - Uses settings.lot_expiry_journal_id

Example:

# Typically called by cron job
get_model("stock.lot").update_expired_lots()

3. Get Life Dates¶

Method: get_life_dates(ids, context)

Calculates 75% and 50% shelf life milestone dates.

Returns:

{
    lot_id: {
        "life_75_date": "2026-03-15",  # 25% consumed
        "life_50_date": "2026-06-15"   # 50% consumed
    }
}

Example:

# Automatically computed when mfg_date and expiry_date set
lot = get_model("stock.lot").browse(lot_id)
print(f"75% life at: {lot.life_75_date}")
print(f"50% life at: {lot.life_50_date}")

4. Get Life Remain Percent¶

Method: get_life_remain(ids, context)

Calculates remaining shelf life percentage.

Returns: Decimal percentage of shelf life remaining

Example:

lot = get_model("stock.lot").browse(lot_id)
if lot.life_remain_percent < 25:
    print(f"Warning: Only {lot.life_remain_percent}% shelf life remaining")

Computed Fields Functions¶

get_life_dates(ids, context)¶

Calculates 75% and 50% shelf life milestone dates based on mfg_date and expiry_date

get_life_remain(ids, context)¶

Returns percentage of shelf life remaining from current date to expiry

get_last_location(ids, context)¶

Finds most recent location from stock movements

get_lot_items_summary(ids, context)¶

Generates summary text of lot items

update_total_mt(ids, context)¶

Sums total weight from lot lines

update_total_pcs(ids, context)¶

Sums total pieces from lot lines

Common Use Cases¶

Use Case 1: Create Lot with Expiry Tracking¶

# Create lot for perishable product
lot_id = get_model("stock.lot").create({
    "product_id": food_product_id,
    "mfg_date": "2025-10-01",
    "expiry_date": "2025-12-31",
    "supp_lot_no": "SUPP-LOT-12345",
    "weight": 100.0,
    "description": "Fresh batch from Farm ABC"
}, context={"sequence_name": "food_lot"})

# Check computed dates
lot = get_model("stock.lot").browse(lot_id)
print(f"Alert at 75% life: {lot.life_75_date}")
print(f"Alert at 50% life: {lot.life_50_date}")

Use Case 2: Serial Number Tracking¶

# Create individual serial numbers for electronics
for serial in ["SN001", "SN002", "SN003"]:
    get_model("stock.lot").create({
        "number": serial,
        "product_id": laptop_product_id,
        "lot_tracking_type": "asset",
        "asset_id": asset_id,
        "description": f"Laptop serial {serial}"
    })

Use Case 3: Equipment Calibration Tracking¶

# Track calibration for measurement equipment
equipment_lot = get_model("stock.lot").create({
    "number": "EQUIP-CAL-001",
    "product_id": equipment_id,
    "lot_tracking_type": "asset",
    "last_calibration_date": "2025-10-01",
    "next_calibration_date": "2026-10-01",
    "equipment_status": "active",
    "machine_number_id": machine_id
})

# Check calibration status
lot = get_model("stock.lot").browse(equipment_lot)
if lot.next_calibration_date < date.today():
    print("Calibration overdue!")

Use Case 4: FIFO/FEFO Lot Selection¶

# Find oldest lots (FIFO - First In First Out)
oldest_lots = get_model("stock.lot").search(
    [["product_id", "=", product_id],
     ["state", "=", "active"]],
    order="received_date"
)

# Find lots expiring soonest (FEFO - First Expired First Out)
expiring_lots = get_model("stock.lot").search(
    [["product_id", "=", product_id],
     ["expiry_date", "!=", None],
     ["state", "=", "active"]],
    order="expiry_date"
)

Best Practices¶

1. Always Set Expiry for Perishable Goods¶

# Good: Set expiry dates
lot_vals = {
    "product_id": product_id,
    "mfg_date": mfg_date,
    "expiry_date": expiry_date  # System calculates life dates
}

# System automatically computes:
# - life_75_date
# - life_50_date  
# - life_remain_percent

2. Use Lot States for Control¶

# Deactivate expired or problematic lots
get_model("stock.lot").write([lot_id], {
    "state": "inactive"  # Excluded from balance calculations
})

# Reactivate if resolved
get_model("stock.lot").write([lot_id], {
    "state": "active"
})

3. Link to Source Documents¶

# Always link to PO for traceability
lot_vals = {
    "number": "LOT-2025-001",
    "product_id": product_id,
    "po_number_id": purchase_order_id,  # Traceability
    "supp_lot_no": supplier_lot_number,  # Supplier reference
    "received_date": datetime.now()
}

Database Constraints¶

Unique Constraint¶

_key = ["number"]

Each lot number must be globally unique across the system.

Model	Relationship	Description
`stock.balance`	One2Many	Stock quantities per location for this lot
`stock.move`	One2Many	All movements of this lot
`product`	Many2One	Product this lot belongs to
`account.fixed.asset`	Many2One	Fixed asset (for asset tracking)
`stock.lot.item`	One2Many	Sub-items within lot
`stock.lot.line`	One2Many	Lot line details
`pick.validate.line`	One2Many	Validation records

Troubleshooting¶

"Lot number must be unique"¶

Cause: Duplicate lot number
Solution: Use unique numbers or let system auto-generate

"Expired lots not moving automatically"¶

Cause: Expiry journal not configured
Solution: Configure settings.lot_expiry_journal_id

"Lot excluded from balance"¶

Cause: Lot state is 'inactive'
Solution: Check lot state and reactivate if appropriate

"Missing shelf life dates"¶

Cause: mfg_date or expiry_date not set
Solution: Set both dates for automatic calculation

Configuration Settings¶

Required Settings¶

Setting	Location	Description
Lot Sequence	Sequences	For auto-generating lot numbers
Expiry Journal	Settings	For automatic expiry movements

This documentation is generated for developer onboarding and reference purposes.

Stock Lot Documentation¶

Overview¶

Model Information¶

Features¶

Lot Tracking Types¶

Lot States¶

Key Fields Reference¶

Header Fields¶

Date Fields¶

Physical Properties¶

Tracking Fields¶

Quality Control Fields¶

Equipment/Asset Fields (for asset tracking)¶

Relationship Fields¶

Computed Fields¶

API Methods¶

1. Create Lot¶

2. Update Expired Lots¶

3. Get Life Dates¶

4. Get Life Remain Percent¶

Computed Fields Functions¶

get_life_dates(ids, context)¶

get_life_remain(ids, context)¶

get_last_location(ids, context)¶

get_lot_items_summary(ids, context)¶

update_total_mt(ids, context)¶

update_total_pcs(ids, context)¶

Common Use Cases¶

Use Case 1: Create Lot with Expiry Tracking¶

Use Case 2: Serial Number Tracking¶

Use Case 3: Equipment Calibration Tracking¶

Use Case 4: FIFO/FEFO Lot Selection¶

Best Practices¶

1. Always Set Expiry for Perishable Goods¶

2. Use Lot States for Control¶

3. Link to Source Documents¶

Database Constraints¶

Unique Constraint¶

Related Models¶

Troubleshooting¶

"Lot number must be unique"¶

"Expired lots not moving automatically"¶

"Lot excluded from balance"¶

"Missing shelf life dates"¶

Configuration Settings¶

Required Settings¶