validator

This is a lightweight validator for Node.JS. It can validate the input string or number based on the rules you defined.

Installation

npm i @sumor/validator --save

Prerequisites

Node.JS version

Require Node.JS version 16.x or above

require Node.JS ES module

As this package is written in ES module, please change the following code in your package.json file:

{
  "type": "module"
}

Usage

Basic Usage

import { validate, format } from '@sumor/validator'

const parameterDefinition = {
  // please refer to the following section for the detail
  rule: [
    {
      code: 'ONLY_CHAR_DIGIT',
      expression: '^[a-zA-Z0-9]*$',
      message: 'only allow a-z, A-Z, 0-9'
    }
  ]
}

// validate the input, return the error message
const messages = validate(parameterDefinition, 'de1234567')
console.log(messages) // [ 'only allow a-z, A-Z, 0-9' ]

// format the input, return the formatted value
const value = format(parameterDefinition, ' demo ')
console.log(value) // will print "demo", useless space will be removed

Parameter Definition

[optional] type data type, support string, number,array,file, default is string
[optional] required required or not, default is false
[optional] length length of the string, default is 0 means no limit
[optional] default default value, default is null
[optional] rule rule for the validation, default is empty array, please refer to the following section for the detail
[optional] trim trim the string or not, default is true for string type
[optional] lowerCase convert the string to lowercase or not, default is false
[optional] upperCase convert the string to uppercase or not, default is false
[optional] decimal decimal for the number, default is null, 0 means no decimal
[optional] i18n i18n for the error message, default is empty object, please refer to the following section for the detail
[optional] error output error or not, default is false

for array type, rule, default, trim, lowerCase, upperCase, decimal are working for each item in the array. for file type, rule is working for the file object.

Rule Definition

code identifier for the rule, translate message based on this code
message original message for the rule
[optional] expression rule expression, should be a regular expression
[optional] function rule function, should be a function, return true if pass the rule

// argument for the function
// value: the value for the parameter
// info: the parameter definition
// language: current language
;(value, info, language) => {
  return value > 5
}

I18n Definition

Structure should be like the following:

{
  "language": {
    "code": "message"
  }
}

language language code, support en, zh, zh-TW and so on
code identifier for the rule, should be the same as the rule code
message translated message for the rule

Validate String Usage

import { validate } from '@sumor/validator'

const parameterDefinition = {
  type: 'string',
  required: true,
  length: 10,
  rule: [
    // only allow a-z, A-Z, 0-9
    {
      code: 'ONLY_CHAR_DIGIT',
      expression: '^[a-zA-Z0-9]*$',
      message: 'only allow a-z, A-Z, 0-9'
    },
    // need include demo
    {
      code: 'INCLUDE_DEMO',
      expression: 'demo',
      message: 'need include demo'
    },
    // use function to check
    {
      code: 'LENGTH_GREATER_THAN_5',
      function: value => {
        return value.length > 5
      },
      message: 'length should be greater than 5'
    }
  ],
  i18n: {
    zh: {
      ONLY_CHAR_DIGIT: '只允许输入字母和数字',
      INCLUDE_DEMO: '需要包含demo',
      LENGTH_GREATER_THAN_5: '长度应大于5'
    },
    'zh-TW': {
      ONLY_CHAR_DIGIT: '只允許輸入字母和數字',
      INCLUDE_DEMO: '需要包含demo',
      LENGTH_GREATER_THAN_5: '長度應大於5'
    }
  }
}

const messages1 = validate(parameterDefinition, 'demo123456')
console.log(messages1) // []

const messages2 = validate(parameterDefinition, 'de1234567')
console.log(messages2) // [ 'only allow a-z, A-Z, 0-9' ]

const messages3 = validate(parameterDefinition, 'demo!')
console.log(messages3) // [ 'only allow a-z, A-Z, 0-9', 'need include demo' ]

const messages4 = validate(parameterDefinition, 'de!mo')
console.log(messages4) // [ 'only allow a-z, A-Z, 0-9', 'need include demo' ]

const messages5 = validate(parameterDefinition, 'de')
console.log(messages5) // [ 'only allow a-z, A-Z, 0-9', 'need include demo', 'length should be greater than 5' ]

// translate to zh
const messages6 = validate(parameterDefinition, 'de', 'zh')
console.log(messages6) // [ '只允许输入字母和数字', '需要包含demo', '长度应大于5' ]

// translate to zh-TW
const messages7 = validate(parameterDefinition, 'de', 'zh-TW')
console.log(messages7) // [ '只允許輸入字母和數字', '需要包含demo', '長度應大於5' ]

Validate Number Usage

import { validate } from '@sumor/validator'

const parameterDefinition = {
  type: 'number',
  required: true,
  rule: [
    // need greater than 5
    {
      code: 'GREATER_THAN_5',
      function: value => {
        return value > 5
      },
      message: 'value should be greater than 5'
    }
  ],
  i18n: {
    zh: {
      GREATER_THAN_5: '值应大于5'
    },
    'zh-TW': {
      GREATER_THAN_5: '值應大於5'
    }
  }
}

const messages1 = validate(parameterDefinition, 6)
console.log(messages1) // []

const messages2 = validate(parameterDefinition, 5)
console.log(messages2) // [ 'value should be greater than 5' ]

const messages3 = validate(parameterDefinition, 4)
console.log(messages3) // [ 'value should be greater than 5' ]

// translate to zh
const messages4 = validate(parameterDefinition, 4, 'zh')
console.log(messages4) // [ '值应大于5' ]

// translate to zh-TW
const messages5 = validate(parameterDefinition, 4, 'zh-TW')
console.log(messages5) // [ '值應大於5' ]

Validate Array Usage

import { validate } from '@sumor/validator'

const parameterDefinition = {
  type: 'array',
  required: true,
  length: 3,
  rule: [
    // need greater than 5
    {
      code: 'GREATER_THAN_5',
      function: value => {
        return value > 5
      },
      message: 'value should be greater than 5'
    },
    // should be a number
    {
      code: 'SHOULD_BE_NUMBER',
      expression: '^[0-9]*$',
      message: 'should be a number'
    }
  ]
}

const messages1 = validate(parameterDefinition, [6, 7, 8])
console.log(messages1) // []

const messages2 = validate(parameterDefinition, [6, 7, '8'])
console.log(messages2) // [ 'should be a number' ]

const messages3 = validate(parameterDefinition, [6, 7, 4])
console.log(messages3) // [ 'value should be greater than 5' ]

const messages4 = validate(parameterDefinition, [6, 7, 4, 5])
console.log(messages4) // [ 'Length must be less than or equal to 3 items', 'value should be greater than 5' ]

Validate File Usage

import { validate } from '@sumor/validator'

const parameterDefinition = {
  type: 'file',
  required: true,
  length: 3,
  rule: [
    // need greater than 5
    {
      code: 'GREATER_THAN_5',
      function: value => {
        return value.size > 5
      },
      message: 'size should be greater than 5'
    }
  ]
}

const messages1 = validate(parameterDefinition, { size: 6 })
console.log(messages1) // []

const messages2 = validate(parameterDefinition, { size: 4 })
console.log(messages2) // [ 'size should be greater than 5' ]

Format String Usage

Trim Usage

will remove the useless space for prefix and suffix

import { format } from '@sumor/validator'

const parameterDefinition = {
  type: 'string',
  trim: true // default is true for string type
}

const value = format(parameterDefinition, ' demo ')
console.log(value) // will print "demo", useless space will be removed

Lowercase Usage

will convert the string to lowercase

import { format } from '@sumor/validator'

const parameterDefinition = {
  type: 'string',
  lowercase: true
}

const value = format(parameterDefinition, 'Demo')
console.log(value) // will print "demo", all characters will be converted to lowercase

Uppercase Usage

will convert the string to uppercase

import { format } from '@sumor/validator'

const parameterDefinition = {
  type: 'string',
  uppercase: true
}

const value = format(parameterDefinition, 'Demo')
console.log(value) // will print "DEMO", all characters will be converted to uppercase

Format Number Usage

import { format } from '@sumor/validator'

const parameterDefinition = {
  type: 'number',
  decimal: 2
}

const value1 = format(parameterDefinition, 1.234)
console.log(value1) // will print 1.23, only keep 2 decimal

const value2 = format(parameterDefinition, '1.234')
console.log(value2) // will convert to number 1.23, only keep 2 decimal

Enable Output Error

If you pass error:true, response will be an SumorError object. You can change language and export json support by @sumor/error

import { validate } from '@sumor/validator'

const parameterDefinition = {
  error: true,
  type: 'string',
  required: true,
  length: 10,
  rule: [
    {
      code: 'LENGTH_GREATER_THAN_5',
      expression: value => {
        return value.length > 5
      },
      message: 'length should be greater than 5'
    }
  ]
}

const messages = validate(parameterDefinition, 'demo123456')
console.log(messages)
/* 
SumorError
{
  code: 'LENGTH_GREATER_THAN_5',
  message: 'length should be greater than 5'
}
*/