1. vue-state-validator

vue-state-validator

VueStateValidator

A simple customizable validator engine for Vue.

See detailed documentation at http://michaelolof.com/docs/vue-state-validator



Installation

 ## Install Module
$ npm install --save vue-state-validator
 // Install Plugin
import Vue from "vue";
import VueStateValidator from "vue-state-validator";

Vue.use(VueStateValidator);

How to use

Define your fields in object like in the data fields shown below.
Here we trigger validation when the submit button is clicked.

 import { required, charRange, wordRange, integer, range, numeric, min, max, validateAndMutate } from "vue-state-validator";

{
  data() {
    return {
      fullname: {  
        value: "John Doe Josh", 
        rules: [required, charRange(3, 25), wordRange(2,2)],
      },
      age: { 
        value: 50, 
        rules: [required, charRange(3, 25), wordRange(2,2)],
      },
      amount: { 
        value: undefined, 
        rules: [required, numeric, min(100), max(100_000)],
      },
    }
  },

  methods: {
    onSubmit() {
      /**
       * Define your validation rules for each field you want to validate. 
       * Here we want to validate:
       *  - Fullname which is required, must be between 3 to 25 characters and exactly 2 words
       *  - Age is required, must be an integer and must be between 12 and 45
       *  - Amount is required must be a number, and must be between 100 and 100,000
       */
      const options = [
        { value: this.fullname.value, rules: this.fullname.rules, err: this.fullname },
        { value: this.age.value, rules: this.age.rules, err: this.age },
        { value: this.amount.value, rules: this.amount.rules, err: this.amount }
      ]

      const isValid = validateAndMutate(options);

      if(isValid === false) return;

      // Continue form submission here...
    }
  }
}

This will validate the fields entered against the rules given and mutate the err object.
This will result in a data object that looks like this:

 {
  data() {
    return {
      fullname: { 
        value: "John Doe Josh", 
        rules: [required, charRange(3, 25), wordRange(2,2)],
        $isWrong: true, 
        $rule: "wordRange" 
      },
      age: {
        value: 50,
        rules: [required, charRange(3, 25), wordRange(2,2)],
        $isWrong: true,
        $rule: "range"
      }
      amount: {
        value: undefined,
        rules: [required, numeric, min(100), max(100_000)],
        $isEmpty: true,
        $rule: "required"
      }
    }
  }
}

You would notice three properties $isEmpty $isWrong and $rule on the err being validated.

VueStateValidator at its core assumes that validation errors can only ever be empty or wrong. This means a validation can either fail because the client didn't enter a value, or the client entered a wrong value.
We also recognize the need to give detailed error messages to provide context to where the failure occured - this is the information the $rule field gives. It lets us know which rule caused validation failure.
If the validation is successfull, $rule is undefined

In your HTML, you'd do some thing like this to display the errors.

 <span v-if="amount.$isEmpty" class="error">Please enter an amount</span>
<span v-else-if="amount.$isWrong && amount.$rule === 'min'" class="error">Minimum amount is 100</span>
<span v-else-if="amount.$isWrong && amount.$rule === 'max'" class="error">Maximum amount is 100,000</span>
<span v-else-if="amount.$isWrong">Please enter a valid amount</span>

Built-in Rules

Syntax Example Description
alpha alpha("One") Checks that the value is alphabetic
alphaNumeric alphaNumeric("One2") Checks that the value is alpha numeric
charRange(number, number) charRange(2, 7)("One") Checks that the length of characters must be between 2 and 7
contains(string) contains("O")("One") Checks if string is in value
decimal decimal(1.2) Checks if value is a decimal
equal equal([1,2,3])([1,2,3]) Checks for deep equality between primitive and non-primitive types
email email("[email protected]") Checks if value is an email address
integer integer(12) Checks if value is an integer
ipAddress ipAddress("127.0.0.1") Checks if value is an IP address
macAddress macAddress("xx:xa:xx:xx:xx:xx") Checks if value is a MAC address
match(RegexExp) match(/[a-zA-Z]+/)("One") Checks if value is matched
matchLength(number) matchLength(3)("One") Checks if length of string is matched
max(number) max(10)(4) Checks if value is <= maximum
maxChar(number) maxChar(10)("One") Checks if length of value is <= maximum
maxWord(number) maxWord(2)("John Doe") Checks if the number of words is <= maximum
min(number) min(2)(4) Checks if the value is >= than minimum
minChar(number) min(3)("One") Checks if length of character is >= minimum
minWord(number) minWord(2)("John D Word") Checks if number of words is >= minimum
notContain(string) notContain("&*")("One") Checks if string is not in value
numeric numeric(1.3) Checks if a value is numeric
range(number, number) range(2, 13)(10) Checks if value is between 2 and 13
required required("One") Checks that a value is not empty
url url("https://www.google.com") Checks if value is a url
wordRange(number, number) wordRange(2, 6)("One Two Three") Checks if number of words is between 2 and 6