Required

Ensure Field Presence and Non-Emptiness

The Required rule in the DataGuard library ensures that a specified field is present in the input data and is not empty. A field is considered "empty" if it meets any of the following conditions:

• The value is None.

• The value is an empty string ("").

• The value is an empty list ([]) or an empty countable object like a dictionary with no items ({}).

This rule is essential for validating fields that must contain data, preventing null or empty values from passing through the validation process.

from data_guard.validator import Validator

# Define data to be validated
data = {'name': None}

# Define validation rules
rules = {'name': ['required']}

# Initialize the validator
validator = Validator(data, rules)

# Perform validation
response = validator.validate()

if response.validated:
    print("Validation passed!", response.data)
else:
    # Output: {'email': ['The name field is required.']}
    print("Validation failed with errors:", response.errors)

Overview:

• Purpose: Ensures a field is not empty.

• Checks: Validates against None, empty strings, and empty collections.

• Result: If the field is empty, an error message indicating that the field is required is generated.