Make serial number field required

[NerosKi]

How can I make the serial number field a required field when adding stock? I've managed to do it for the batch code by implementing a custom plugin:

from plugin import InvenTreePlugin
from plugin.mixins import ValidationMixin
from django.core.exceptions import ValidationError

class IPNValidationPlugin(ValidationMixin, InvenTreePlugin):
    NAME = 'Additional custom Validation'
    SLUG = 'customvalidation'
    TITLE = 'Additional Validation Plugin'

    def validate_batch_code(self, batch_code, item):
        if not batch_code:
            raise ValidationError("Batch Code cannot be empty")

    def validate_serial_number(self, serial, part, stock_item):
        # Ensure that a serial number has been provided
        if not serial or not serial.strip():
            raise ValidationError("Serial number cannot be empty")

        # Check if the serial number is numeric.
        # Here, we try to convert it to an integer.
        try:
            int(serial)
        except ValueError:
            raise ValidationError("Serial number must be a valid number")

However the validate_serial_number function does not trigger when the field is empty, unlike the validate_batch_code. When I put e.g. "aaa" in the lot number I do get a validation error but when it is empty, it accepts it without error.

Also when adding new stock, since that field is different, it is possible to add stock there without a serial number

[NerosKi]

I also tried it with the model but then it always says that "Serial number cannot be empty"

from plugin import InvenTreePlugin
from plugin.mixins import ValidationMixin
from django.core.exceptions import ValidationError

import part.models
import stock.models

class CustomValidationPlugin(ValidationMixin, InvenTreePlugin):
    NAME = 'Additional Custom Validation'
    SLUG = 'customvalidation'
    TITLE = 'Additional Validation Plugin'
    DESCRIPTION = 'Ensures that the serial number and batch code are mandatory for stock items.'

    def validate_model_instance(self, instance, deltas=None):
        """Model-level validation for all models

        Check this for variable names:
        https://docs.inventree.org/en/latest/report/context_variables/
        
        This example checks StockItem objects to ensure they have valid 'serial' and 'batch_code' fields.
        """

        # Check if the instance is a Part
        if isinstance(instance, part.models.Part):
            errors = {}
            if not instance.IPN:
                errors['IPN'] = "IPN cannot be empty"

            if errors:
                self.raise_error(errors)
        
        # Check if the instance is a StockItem
        if isinstance(instance, stock.models.StockItem):
            errors = {}

            # Validate the serial number
            if not instance.serial:
                errors['serial'] = "Serial number cannot be empty"
            else:
                try:
                    int(instance.serial)
                except ValueError:
                    errors['serial'] = "Serial number must be a valid number"

            # Validate the batch code
            if not instance.batch:
                errors['batch'] = "Batch code cannot be empty"

            if errors:
                # This helper method raises a ValidationError with the specified errors
                self.raise_error(errors)

[NerosKi]

It does work when I try to edit existing stock and then put in an empty serial or letters. But not when creating new stock. I assume because the field there (Serial Numbers) is not the same thing. How can I solve this? I never want to have stock that does not have a serial number assigned.

[SchrodingersGat]

@NerosKi I think the issue might be here:

InvenTree/src/backend/InvenTree/stock/models.py

Line 712 in a3be8e9

try:

Can you try changing the code from:

        # If the serial number is set, make sure it is not a duplicate
        if self.serial:
            self.serial = str(self.serial).strip()

            try:
                self.part.validate_serial_number(self.serial, self, raise_error=True)
            except ValidationError as exc:
                raise ValidationError({'serial': exc.message})

to

        # If the serial number is set, make sure it is not a duplicate
        if self.serial:
            self.serial = str(self.serial).strip()

        try:
            self.part.validate_serial_number(self.serial, self, raise_error=True)
        except ValidationError as exc:
            raise ValidationError({'serial': exc.message})

This will run the serial number through the custom validator, even if it is empty. Currently this is not checked.