SwiftValidate

enhanced validation for swift

By Danilo Topalovic.

• Introduction
• Requirements
• Installation
• Usage
• Included Validators
  • Required
  • Empty
  • StrLen
  • Charset
  • Alnum
  • Email
  • Regex
  • Numeric
  • Between
  • GreaterThan
  • SmallerThan
  • DateTime
  • DateBetween
  • Callback
  • InArray
• Extensibility

Introduction

Unfortunately I did not find a fancy name for this software so I've called it what it is - a validator.

Heavily inspired by Zend\Validate and Eureka I started working on this component and I still add tests / validators. if you encounter any issues or bugs please feel free to report the bug or even write a test for this bug in order to be good again when the bug is solved.

See also the ExampleProject

If you are also missing a kind of filtering for form inputs see SwiftFilter

Requirements

• iOS 8.0+
• Xcode 7.0+

Installation

See CocoaPods for easy installation into your project

Add SwiftValidate to your Podfile like

pod 'SwiftValidate', '~> 2.0.1'

and then run pod install in your directory as usual.

Of course you can use it in Carthage as well

github "dtop/SwiftValidate"

Usage

All validators are usable completely on their own but one of the main advantages of SwiftValidate is that the validators are chainable. Add as many validators to a single chain as you need for properly validate your value.

Add import SwiftValidate to your View Controller.

And then, you're all setup to start using it:

let validatorChain = ValidatorChain() {
    $0.stopOnFirstError = true
    $0.stopOnException = true
} <~~ ValidatorRequired() {
    $0.errorMessage = "Enter the value!"
} <~~ ValidatorEmpty() {
    $0.allowNil = false
} <~~ ValidatorStrLen() {
    $0.minLength = 3
    $0.maxLength = 30
    $0.errorMessageTooSmall = "My fancy own error message"
}

let myValue = "testValue"

let result = validatorChain.validate(myValue, context: nil)
let errors = validatorChain.errors

If you are dealing with a lot of values (e.g. a form result) you can easily predefine an ValidationIterator and add several chains linked to the form fields name to it.

see the extraction of the ValidationIteratorTests:

        // form values given by some user
        let formResults: [String: Any?] = [
            "name": "John Appleseed",
            "street": "1456 Sesame Street",
            "zipcode": "01526",
            "city": "Somewhere",
            "country": nil
        ]
        
        let validationIterator = ValidationIterator() {
            $0.resultForUnknownKeys = true
        }
        
        // name, street, city
        validationIterator.register(
            chain: ValidatorChain() {
                    $0.stopOnException = true
                    $0.stopOnFirstError = true
                }
                <~~ ValidatorRequired()
                <~~ ValidatorEmpty()
                <~~ ValidatorStrLen() {
                    $0.minLength = 3
                    $0.maxLength = 50
                },
            forKeys: ["name", "street"]
        )
        
        // zipcode
        validationIterator.register(
            chain: ValidatorChain() {
                $0.stopOnException = true
                $0.stopOnFirstError = true
            }
            <~~ ValidatorRequired()
            <~~ ValidatorStrLen() {
                $0.minLength = 5
                $0.maxLength = 5
            }
            <~~ ValidatorNumeric() {
                $0.allowString = true
                $0.allowFloatingPoint = false
            },
            forKey: "zipcode"
        )
        
        // country (not required but if present between 3 and 50 chars)
        validationIterator.register(
            chain: ValidatorChain() {
                $0.stopOnException = true
                $0.stopOnFirstError = true
            }
            <~~ ValidatorStrLen() {
                $0.minLength = 3
                $0.maxLength = 50
            },
            forKey: "country"
        )
        
        
        let validationResult = validationIterator.validate(formResults)
        let cityInError = validationIterator.isInError("city")

see WiKi for more examples and explinations

Included Validators

ValidatorRequired()

Since all other validators allow nil from default setting, this validator can be added first to check the value is present. It is also equipped with a callback where you can decide by value and context if the requiry is satisfied or not.

Configuration

Configuration

value	type	default	description
requirementCondition	closure	?	optional custom requirement check

Error Messages

• errorMessage - error message if value is nil

---

ValidatorEmpty()

Tests if the given value is not an empty string

Configuration

value	type	default	description
allowNil	Bool	true	value can be nil

Error Messages

• errorMessage - error message if value is empty

---

ValidatorStrLen()

Tests if a given value is between min and max in strlen

Configuration

value	type	default	description
allowNil	Bool	true	value an be nil
minLength	Int	3	minimum length of string
maxLength	Int	30	maximum length of string
minInclusive	Bool	true	minimum inclusive in value
maxInclusive	Bool	true	maximum inclusive in value

Error Messages

• errorMessageTooSmall: String - error message if string is not long enaugh
• errorMessageTooLarge: String- error message if string is too long

---

ValidatorCharset()

Validates that the given value contains only chars from the given character set

configuration

value	type	default	description
allowNil	Bool	true	value an be nil
allowEmpty	Bool	false	value can be empty
charset	NSCharacterSet	!	charset to compare

Error Messages

• errorMessageStringDoesNotFit: String - (optional)

---

ValidatorAlnum()

Validates if the given value consists of alpha numerical chars only

This is a specialization of ValidatorCharset()

---

ValidatorEmail()

Validates a given email address

Configuration

value	type	default	description
allowNil	Bool	true	value an be nil
validateLocalPart	Bool	true	the local part of the mail address will be validated
validateHostnamePart	Bool	true	the hostname part of the mail address will be validated
validateTopLevelDomain	Bool	true	the address has to have a topleveldomain
strict	Bool	true	the length of the parts will also be validated

Error Messages

• errorMessageInvalidAddress - address is invalid
• errorMessageInvalidLocalPart - the local part (before @) is invalid
• errorMessageInvalidHostnamePart - the hostname is invalid
• errorMessagePartLengthExceeded - a part is exceeding its length

---

ValidatorRegex()

Validates a given string against a user definded regex

value	type	default	description
allowNil	Bool	true	nil is allowed
pattern	String	-	the pattern to match against
options	NSRegularExpressionOptions	0	options for the regular expression
matchingOptions	NSMatchingOptions	0	options for the matching

Error Messages

• errorMessageValueIsNotMatching - value does not match teh given pattern

---

ValidatorNumeric()

Validates if the given value is a valid number

Configuration

value	type	default	description
allowNil	Bool	true	nil is allowed
allowString	Bool	true	value can be a numerical string
allowFloatingPoint	Bool	true	value can be a floatingpoint value

Error Messages

• errorMessageNotNumeric - value is not numeric

---

ValidatorBetween()

Validates if a numerical value is between 2 predefined values

Generic:

let validator = ValidatorBetween<Double>() {
    $0.minValue = 1.0
    $0.maxValue = 99.1
}

Configuration

value	type	default	description
allowNil	Bool	true	nil is allowed
allowString	Bool	true	value can be a numerical string
minValue	TYPE	0	the minimum value
maxValue	TYPE	0	the maximum value
minInclusive	Bool	true	minimum value inclusive (>= instead of >)
maxInclusive	Bool	true	maximum value inclusive

Error Messages

• errorMessageInvalidType - invalid type given [-should be thrown-]
• errorMessageNotBetween - value is not between the predefined values

---

ValidatorGreaterThan()

Validates if the given value is greater than the predefined one

Generic:

let validator = ValidatorGreaterThan<Double>() {
    $0.min = 1.0
}

Configuration

value	type	default	description
allowNil	Bool	true	nil is allowed
min	TYPE	0	the value that needs to be exceeded
inclusive	Bool	true	value itself inclusive

Error Messages

• errorMessageInvalidType - invalid type given [-should be thrown-]
• errorMessageNotGreaterThan - value is not great enaugh

---

ValidatorSmallerThan()

Validates if the given value is smaller than the predefined one

Generic:

let validator = ValidatorSmallerThan<Double>() {
    $0.max = 10.0
}

Configuration

value	type	default	description
allowNil	Bool	true	nil is allowed
max	TYPE	0	the value that needs to be exceeded
inclusive	Bool	true	value itself inclusive

Error Messages

• errorMessageInvalidType - invalid type given [-should be thrown-]
• errorMessageNotSmallerThan - value is not small enaugh

---

ValidatorDateTime()

Validates if the given date is a valid one

Configuration

value	type	default	description
allowNil	Bool	true	nil is allowed
dateFormat	String	0	the date format to be parsed

Error Messages

• errorMessageInvalidDate - invalid date given

---

ValidatorDateBetween()

Validates if the given date (NSDate or String) is between the predefined dates

Configuration

value	type	default	description
allowNil	Bool	true	nil is allowed
min	NSDate	!	minimum date
max	NSDate	!	maximum date
minInclusive	Bool	true	minimum value inclusive (>= instead of >)
maxInclusive	Bool	true	maximum value inclusive
dateFormatter	NSDateFormatter	!	date formatter for parsing the string if string is expected

Error Messages

• errorMessageNotBetween - Date is not between the predefined ones

---

ValidatorCallback()

Executes the given callback and works with the results

Configuration

value	type	default	description
allowNil	Bool	true	nil is allowed
callback	closure	!	the callback to validate with

Callback be like:

let validator = ValidatorCallback() {
    $0.callback = {(validator: ValidatorCallback, value: Any?, context: [String : Any?]?) in
        
        if nil == value {
            /// you can throw
            throw NSError(domain: "my domain", code: 1, userInfo: [NSLocalizedDescriptionKey: "nil!!"])
        }
        
        return (false, "My Error Message")
        /// return (true, nil)
    }
}

---

ValidatorInArray()

Validates that the given value is contained in the predefined array

Generic:

let validator = ValidatorInArray<String>() {
    $0.array = ["Andrew", "Bob", "Cole", "Dan", "Edwin"]
}

let validator = ValidatorInArray<Double>() {
    $0.allowNil = false
    $0.array = [2.4, 3.1, 9.8, 4.9, 2.0]
}

Configuration

value	type	default	description
allowNil	Bool	true	nil is allowed
array	[TYPE]	[]	the array with predefined values

Error Messages

• errorMessageItemIsNotContained - given value is not contained in the array

Extensibility

Non generic:

class MyValidator: BaseValidator, ValidatorProtocol {

    required public init( _ initializer: @noescape(MyValidator) -> () = { _ in }) {
        super.init()
        initializer(self)
    }
    
    override func validate<T: Any>( _ value: T?, context: [String: Any?]?) throws -> Bool {
        /// ...
    }
}

Generic:

class MyGenericValidator<TYPE where TYPE: Equatable>: ValidatorProtocol, ValidationAwareProtocol {

    required public init( _ initializer: @noescape(MyGenericValidator) -> () = { _ in }) {
        initializer(self)
    }

    public func validate<T: Any>( _ value: T?, context: [String: Any?]?) throws -> Bool {
        /// ...
    }
}