Validator Class Documentation

The Validator class is responsible for validating data using different validation strategies. It allows you to set and switch between different validation strategies based on your specific requirements.

Class Signature

class Validator {
    private ValidationStrategy $strategy;

    public function __construct(ValidationStrategy $strategy);
    public function setValidationStrategy(ValidationStrategy $strategy): void;
    public function validateData($data): mixed;
    public function validateDataWithErrors($data): array;
}

Constructor

__construct(ValidationStrategy $strategy)

The constructor accepts a ValidationStrategy object as a parameter, which determines the specific validation strategy to use. The initial validation strategy is set during object creation.

Public Methods

setValidationStrategy(ValidationStrategy $strategy): void

This method allows you to set a new validation strategy by providing a ValidationStrategy object as a parameter. It replaces the existing validation strategy with the new one.

validateData($data): mixed

The validateData method is used to perform data validation using the current validation strategy. It accepts the data to be validated as a parameter and returns the validation result.

validateDataWithErrors($data): array

The validateDataWithErrors method performs data validation and returns an array containing the validation status and any errors, if applicable. If the strategy object has a getErrors method, the errors will be included in the array.

• Parameters:

  • $data: The data to be validated.

• Return:

  • Returns the validation result, which depends on the specific validation strategy being used. It can be a boolean value (true for a successful validation, false otherwise) or other data types based on the strategy implementation or an array with the validation status and errors, if any.

Usage Example

Here's an example that demonstrates the basic usage of the Validator class:

// Create a validator with a specific validation strategy
$validator = new Validator($requiredFieldsStrategy);

// Set a new validation strategy if needed
$validator->setValidationStrategy($customValidationStrategy);

// Perform data validation
$data = $_POST; // Example data to be validated
$result = $validator->validateData($data);

// Perform data validation with errors
$resultWithErrors = $validator->validateDataWithErrors($data);

// Check the validation result
if ($result === true) {
    echo "Validation passed! The data is valid.";
} elseif (isset($resultWithErrors['errors'])) {
    echo "Validation failed! Errors: " . implode(', ', $resultWithErrors['errors']);
} else {
    echo "Validation failed! Please check the data for errors.";
}

In the example above:

1. The Validator class is instantiated with an initial validation strategy ($requiredFieldsStrategy).
2. If needed, you can use the setValidationStrategy method to switch to a different validation strategy.
3. The validateData and validateDataWithErrors methods are called with the data to be validated ($data).
4. The returned results are checked to determine if the validation passed or failed.
5. Based on the validation results, you can perform appropriate actions or display error messages.

Note: The specific validation strategies used ($requiredFieldsStrategy and $customValidationStrategy) are not shown in the example, as they depend on your specific implementation.