Swift-validator

Swift Validator is a rule-based validation library for Swift.

Core Concepts

• UITextField and ValidationRule go into the Validator, UITextFields and ValidationErrors come out of Validator
• UITextField is registered to Validator
• Validator evaluates ValidationRules sequentially and stops evaluating when a ValidationRule fails.

Quick Start

Initialize the Validator by setting a delegate to a View Controller or other object.

// ViewController.swift

override func viewDidLoad() {
        super.viewDidLoad()
        
        var validator = Validator(delegate: self)
}

Register the fields that you want to validate

var fields:[String] = ["FullName", "Email", "Phone"]

// Validation Rules are evaluated from left to right. The first rule is ValidationRuleType.Required the second is ValidationRuleType.FullName.
validator.registerField(fields[0], textField:nameTextField, rules: [.Required, .FullName])
validator.registerField(fields[1], textField:emailTextField, rules: [.Required, .Email])
validator.registerField(fields[2], textField:phoneTextField, rules: [.Required, .PhoneNumber])

Validate Individual Field

func validator.validateFieldBy(fields[0], delegate:self)

// ValidationFieldDelegate methods
func validationFieldSuccess(key:String, validField:UITextField){
	validField.backgroundColor = UIColor.greenColor()
}

func validationFieldFailure(key:String, error:ValidationError){
	println(error.error.description)
}

Validate All Fields

validator.validateAllBy(fields, delegate:self)

// ValidationDelegate methods

func validationWasSuccessful(){
	// submit the form
}

func validationFailed(key:String, errors[String:ValidationError]){
	// turn the fields to red
	for error in errors.values {
		error.textField.backgroundColor = UIColor.redColor()
		println("error -> \(error.error.description)")
	}
}

Custom Validation

We will create a SSNValidation class to show how to create your own Validation. A United States Social Security Number (or SSN) is a field that consists of XXX-XX-XXXX.

Create a class that implements the Validation protocol

class SSNValidation: Validation {
    let SSN_REGEX = "^\\d{3}-\\d{2}-\\d{4}$"
    
    func validate(value: String) -> (Bool, ValidationErrorType) {
        if let ssnTest = NSPredicate(format: "SELF MATCHES %@", SSN_REGEX) {
            if ssnTest.evaluateWithObject(value) {
                return (true, .NoError)
            }
            return (false, .SocialSecurity) // We will create this later ValidationErrorTYpe
        }
        return (false, .SocialSecurity)
    }
    
}

Add the .SocialSecurity ValidationRuleType

enum ValidationRuleType {
    case Required,
    Email,
    Password,
    MinLength,
    MaxLength,
    ZipCode,
    PhoneNumber,
    FullName,
    SocialSecurity	// Added to the Rule Types
}

Add the .SocialSecurity ValidationErrorType and description()

enum ValidationErrorType {
    case Required,
    Email,
    Password,
    MinLength,
    MaxLength,
    ZipCode,
    PhoneNumber,
    FullName,
    SocialSecurity,	// Added to the Error Types
    NoError
    
    func description() -> String {
        switch self {
        case .Required:
            return "Required field"
        case .Email:
            return "Must be a valid email"
        case .MaxLength:
            return "This field should be less than"
        case .ZipCode:
            return "5 digit zipcode"
        case .PhoneNumber:
            return "10 digit phone number"
        case .Password:
            return "Must be at least 8 characters"
        case .FullName:
            return "Provide a first & last name"
        // Adding the desired error message
        case .SocialSecurity:
        	return "SSN is XXX-XX-XXXX"
        default:
            return ""
        }
    }
    
}

Register the Validation with the ValidationFactory

class ValidationFactory {
    class func validationForRule(rule:ValidationRuleType) -> Validation {
        switch rule {
        case .Required:
            return RequiredValidation()
        case .Email:
            return EmailValidation()
        case .MinLength:
            return MinLengthValidation()
        case .MaxLength:
            return MaxLengthValidation()
        case .PhoneNumber:
            return PhoneNumberValidation()
        case .ZipCode:
            return ZipCodeValidation()
        case .FullName:
            return FullNameValidation()
        // Add Validation to allow Factory to create one on the fly for you
        case .SocialSecurity:
        	return SSNValidation()
        default:
            return RequiredValidation()
        }
    }
}