Object-checker NPM

object-checker-js

Notice: the package is updated to v1.0.0 and APIs are changed:

API	before `v1.0.0`	after `v1.0.0`
`isValid()`	Check the object and throw Exceptions when invalid	Renamed to `verify()`
`checkObject()`	Check the object and return check result.	Renamed to `check()`
`isValidObject()`	Check the object and return `true`/`false` for result	Renamed to `isValid()`
`bodyCheckMiddleware`	Middleware for express	Renamed to `expressBodyCheckMiddleware`
`errorHandler`	Handler for middleware	Renamed to `expressErrorHandler`

A tool for checking object. And also provide a middleware for express.

No validation codes.
Easy to combine with other validation package.
Can make router.js in Express as an API document.

Quick Example:

var objectChecker = require('object-checker');

var checker = objectChecker.createObjectChecker()
var obj = {
  users: [
    {
      name:"a@a.com",
      additional:{
        age   : 20,
        height: 180,
        score : [80, 90, 100]
      }
    },
    {
      name:"123@b.com"
    },
    {
      name:"123@a.com",
      additional: {
        age   : 100,
        height:200,
        score : [60, 70, 80, 90]
      }
    }
  ]
};

var opt = {
  users: {
    $maxLength: 5,
    $: {
      name: {
        $isEmail  : true,
        $minLength: 6,
        $maxLength: 10
      },
      additional: {
        $isOptional: true,
        age: {
          $minValue: 20,
          $maxValue: 100
        },
        height: {
          $minValue: 100,
          $maxValue: 200
        },
        score: {
          $minLength: 3,
          $: {
            $minValue: 60,
            $maxValue: 100
          }
        }
      }
    }
  }
};

console.log(checker.check(obj, opt));

Use as an Express Middleware

// router.js

var express                    = require('express');
var expressBodyCheckMiddleware = require('object-checker').expressBodyCheckMiddleware;

var router = express.Router();

var opt = {
  username: {
    $isEmail: true
  },
  password: {
    $minLength: 6,
    $maxLength: 20
  }
};
router.post('/users', expressBodyCheckMiddleware(opt), handlerFunction);

module.exports = router;

Play with other modules

// router.js

var express                    = require('express');
var expressBodyCheckMiddleware = require('object-checker').expressBodyCheckMiddleware;
var validator                  = require('validator'); // 3rd-part validator module

var router = express.Router();

var opt = {
  username: {
    $assertTrue: validator.isEmail  // 3rd-part validator function(value){...}
  },
  password: {
    $minLength: 6,
    $maxLength: 20
  }
};
router.post('/users', expressBodyCheckMiddleware(opt), handlerFunction);

module.exports = router;

Custom customDirectives and messageTemplate

var objectChecker = require('../object-checker');
var checker = objectChecker.createObjectChecker({
  customDirectives: {
    $doNotCheck: null,
    $inRange: function(value, option) { return option.min < value && value < option.max;}
  },
  messageTemplate: {
    invalid   : "Value of Field `{{fieldName}}` is not valid. Got `{{fieldValue}}`, but require {{checkerName}} = {{checkerOption}}",
    missing   : "Missing {{fieldName}}",
    unexpected: "Not support {{fieldName}}"
  }
};

checker.verify(yourObject);

Custom error message and error handler in middleware (javascript)

var objectChecker = require('../object-checker');
objectChecker.messageTemplate = {
  invalid   : "Value of Field `{{fieldName}}` is not valid. Got `{{fieldValue}}`, but require {{checkerName}} = {{checkerOption}}",
  missing   : "Missing {{fieldName}}",
  unexpected: "Not support {{fieldName}}"
};

var objectChecker = require('../object-checker');
objectChecker.expressErrorHandler = function(err, req, res, next) {
  console.log(err);
  var template = {
    "invalid"   : "invalid request",
    "missing"   : "missing parameter",
    "unexpected": "found unexpected parameter"
  };
  res.send({
    err: 400,
    msg: objectChecker.createErrorMessage(err, template);
  });
};