backbone-validation.js

Backbone.Validation v0.8.1

Copyright (c) 2011-2013 Thomas Pedersen Distributed under MIT License

Documentation and full license available at: http://thedersen.com/projects/backbone-validation

Backbone.Validation = (function(_){
  'use strict';

Default options

  var defaultOptions = {
    forceUpdate: false,
    selector: 'name',
    labelFormatter: 'sentenceCase',
    valid: Function.prototype,
    invalid: Function.prototype
  };

Helper functions

Formatting functions used for formatting error messages

  var formatFunctions = {

Uses the configured label formatter to format the attribute name to make it more readable for the user

    formatLabel: function(attrName, model) {
      return defaultLabelFormatters[defaultOptions.labelFormatter](attrName, model);
    },

Replaces nummeric placeholders like {0} in a string with arguments passed to the function

    format: function() {
      var args = Array.prototype.slice.call(arguments),
          text = args.shift();
      return text.replace(/\{(\d+)\}/g, function(match, number) {
        return typeof args[number] !== 'undefined' ? args[number] : match;
      });
    }
  };

Flattens an object eg:

var o = {
  address: {
    street: 'Street',
    zip: 1234
  }
};

becomes:

var o = {
  'address.street': 'Street',
  'address.zip': 1234
};
  var flatten = function (obj, into, prefix) {
    into = into || {};
    prefix = prefix || '';

    _.each(obj, function(val, key) {
      if(obj.hasOwnProperty(key)) {
        if (val && typeof val === 'object' && !(
          val instanceof Array ||
          val instanceof Date ||
          val instanceof RegExp ||
          val instanceof Backbone.Model ||
          val instanceof Backbone.Collection)
        ) {
          flatten(val, into, prefix + key + '.');
        }
        else {
          into[prefix + key] = val;
        }
      }
    });

    return into;
  };

Validation

  var Validation = (function(){

Returns an object with undefined properties for all attributes on the model that has defined one or more validation rules.

    var getValidatedAttrs = function(model) {
      return _.reduce(_.keys(model.validation || {}), function(memo, key) {
        memo[key] = void 0;
        return memo;
      }, {});
    };

Looks on the model for validations for a specified attribute. Returns an array of any validators defined, or an empty array if none is defined.

    var getValidators = function(model, attr) {
      var attrValidationSet = model.validation ? model.validation[attr] || {} : {};

If the validator is a function or a string, wrap it in a function validator

      if (_.isFunction(attrValidationSet) || _.isString(attrValidationSet)) {
        attrValidationSet = {
          fn: attrValidationSet
        };
      }

Stick the validator object into an array

      if(!_.isArray(attrValidationSet)) {
        attrValidationSet = [attrValidationSet];
      }

Reduces the array of validators into a new array with objects with a validation method to call, the value to validate against and the specified error message, if any

      return _.reduce(attrValidationSet, function(memo, attrValidation) {
        _.each(_.without(_.keys(attrValidation), 'msg'), function(validator) {
          memo.push({
            fn: defaultValidators[validator],
            val: attrValidation[validator],
            msg: attrValidation.msg
          });
        });
        return memo;
      }, []);
    };

Validates an attribute against all validators defined for that attribute. If one or more errors are found, the first error message is returned. If the attribute is valid, an empty string is returned.

    var validateAttr = function(model, attr, value, computed) {

Reduces the array of validators to an error message by applying all the validators and returning the first error message, if any.

      return _.reduce(getValidators(model, attr), function(memo, validator){

Pass the format functions plus the default validators as the context to the validator

        var ctx = _.extend({}, formatFunctions, defaultValidators),
            result = validator.fn.call(ctx, value, attr, validator.val, model, computed);

        if(result === false || memo === false) {
          return false;
        }
        if (result && !memo) {
          return validator.msg || result;
        }
        return memo;
      }, '');
    };

Loops through the model's attributes and validates them all. Returns and object containing names of invalid attributes as well as error messages.

    var validateModel = function(model, attrs) {
      var error,
          invalidAttrs = {},
          isValid = true,
          computed = _.clone(attrs),
          flattened = flatten(attrs);

      _.each(flattened, function(val, attr) {
        error = validateAttr(model, attr, val, computed);
        if (error) {
          invalidAttrs[attr] = error;
          isValid = false;
        }
      });

      return {
        invalidAttrs: invalidAttrs,
        isValid: isValid
      };
    };

Contains the methods that are mixed in on the model when binding

    var mixin = function(view, options) {
      return {

Check whether or not a value passes validation without updating the model

        preValidate: function(attr, value) {
          return validateAttr(this, attr, value, _.extend({}, this.attributes));
        },

Check to see if an attribute, an array of attributes or the entire model is valid. Passing true will force a validation of the model.

        isValid: function(option) {
          var flattened = flatten(this.attributes);

          if(_.isString(option)){
            return !validateAttr(this, option, flattened[option], _.extend({}, this.attributes));
          }
          if(_.isArray(option)){
            return _.reduce(option, function(memo, attr) {
              return memo && !validateAttr(this, attr, flattened[attr], _.extend({}, this.attributes));
            }, true, this);
          }
          if(option === true) {
            this.validate();
          }
          return this.validation ? this._isValid : true;
        },

This is called by Backbone when it needs to perform validation. You can call it manually without any parameters to validate the entire model.

        validate: function(attrs, setOptions){
          var model = this,
              validateAll = !attrs,
              opt = _.extend({}, options, setOptions),
              validatedAttrs = getValidatedAttrs(model),
              allAttrs = _.extend({}, validatedAttrs, model.attributes, attrs),
              changedAttrs = flatten(attrs || allAttrs),

              result = validateModel(model, allAttrs);

          model._isValid = result.isValid;

After validation is performed, loop through all changed attributes and call the valid callbacks so the view is updated.

          _.each(validatedAttrs, function(val, attr){
            var invalid = result.invalidAttrs.hasOwnProperty(attr);
            if(!invalid){
              opt.valid(view, attr, opt.selector);
            }
          });

After validation is performed, loop through all changed attributes and call the invalid callback so the view is updated.

          _.each(validatedAttrs, function(val, attr){
            var invalid = result.invalidAttrs.hasOwnProperty(attr),
                changed = changedAttrs.hasOwnProperty(attr);

            if(invalid && (changed || validateAll)){
              opt.invalid(view, attr, result.invalidAttrs[attr], opt.selector);
            }
          });

Trigger validated events. Need to defer this so the model is actually updated before the event is triggered.

          _.defer(function() {
            model.trigger('validated', model._isValid, model, result.invalidAttrs);
            model.trigger('validated:' + (model._isValid ? 'valid' : 'invalid'), model, result.invalidAttrs);
          });

Return any error messages to Backbone, unless the forceUpdate flag is set. Then we do not return anything and fools Backbone to believe the validation was a success. That way Backbone will update the model regardless.

          if (!opt.forceUpdate && _.intersection(_.keys(result.invalidAttrs), _.keys(changedAttrs)).length > 0) {
            return result.invalidAttrs;
          }
        }
      };
    };

Helper to mix in validation on a model

    var bindModel = function(view, model, options) {
      _.extend(model, mixin(view, options));
    };

Removes the methods added to a model

    var unbindModel = function(model) {
      delete model.validate;
      delete model.preValidate;
      delete model.isValid;
    };

Mix in validation on a model whenever a model is added to a collection

    var collectionAdd = function(model) {
      bindModel(this.view, model, this.options);
    };

Remove validation from a model whenever a model is removed from a collection

    var collectionRemove = function(model) {
      unbindModel(model);
    };

Returns the public methods on Backbone.Validation

    return {

Current version of the library

      version: '0.8.1',

Called to configure the default options

      configure: function(options) {
        _.extend(defaultOptions, options);
      },

Hooks up validation on a view with a model or collection

      bind: function(view, options) {
        var model = view.model,
            collection = view.collection;

        options = _.extend({}, defaultOptions, defaultCallbacks, options);

        if(typeof model === 'undefined' && typeof collection === 'undefined'){
          throw 'Before you execute the binding your view must have a model or a collection.\n' +
                'See http://thedersen.com/projects/backbone-validation/#using-form-model-validation for more information.';
        }

        if(model) {
          bindModel(view, model, options);
        }
        else if(collection) {
          collection.each(function(model){
            bindModel(view, model, options);
          });
          collection.bind('add', collectionAdd, {view: view, options: options});
          collection.bind('remove', collectionRemove);
        }
      },

Removes validation from a view with a model or collection

      unbind: function(view) {
        var model = view.model,
            collection = view.collection;

        if(model) {
          unbindModel(view.model);
        }
        if(collection) {
          collection.each(function(model){
            unbindModel(model);
          });
          collection.unbind('add', collectionAdd);
          collection.unbind('remove', collectionRemove);
        }
      },

Used to extend the Backbone.Model.prototype with validation

      mixin: mixin(null, defaultOptions)
    };
  }());

Callbacks

  var defaultCallbacks = Validation.callbacks = {

Gets called when a previously invalid field in the view becomes valid. Removes any error message. Should be overridden with custom functionality.

    valid: function(view, attr, selector) {
      view.$('[' + selector + '~="' + attr + '"]')
          .removeClass('invalid')
          .removeAttr('data-error');
    },

Gets called when a field in the view becomes invalid. Adds a error message. Should be overridden with custom functionality.

    invalid: function(view, attr, error, selector) {
      view.$('[' + selector + '~="' + attr + '"]')
          .addClass('invalid')
          .attr('data-error', error);
    }
  };

Patterns

  var defaultPatterns = Validation.patterns = {

Matches any digit(s) (i.e. 0-9)

    digits: /^\d+$/,

Matched any number (e.g. 100.000)

    number: /^-?(?:\d+|\d{1,3}(?:,\d{3})+)(?:\.\d+)?$/,

Matches a valid email address (e.g. mail@example.com)

    email: /^((([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+(\.([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+)*)|((\x22)((((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(([\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|\x21|[\x23-\x5b]|[\x5d-\x7e]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(\\([\x01-\x09\x0b\x0c\x0d-\x7f]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))))*(((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(\x22)))@((([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.)+(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))$/i,

Mathes any valid url (e.g. http://www.xample.com)

    url: /^(https?|ftp):\/\/(((([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:)*@)?(((\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5])\.(\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5])\.(\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5])\.(\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5]))|((([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.)+(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.?)(:\d*)?)(\/((([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:|@)+(\/(([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:|@)*)*)?)?(\?((([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:|@)|[\uE000-\uF8FF]|\/|\?)*)?(\#((([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:|@)|\/|\?)*)?$/i
  };

Error messages

Error message for the build in validators. {x} gets swapped out with arguments form the validator.

  var defaultMessages = Validation.messages = {
    required: '{0} is required',
    acceptance: '{0} must be accepted',
    min: '{0} must be greater than or equal to {1}',
    max: '{0} must be less than or equal to {1}',
    range: '{0} must be between {1} and {2}',
    length: '{0} must be {1} characters',
    minLength: '{0} must be at least {1} characters',
    maxLength: '{0} must be at most {1} characters',
    rangeLength: '{0} must be between {1} and {2} characters',
    oneOf: '{0} must be one of: {1}',
    equalTo: '{0} must be the same as {1}',
    pattern: '{0} must be a valid {1}'
  };

Label formatters

Label formatters are used to convert the attribute name to a more human friendly label when using the built in error messages. Configure which one to use with a call to

Backbone.Validation.configure({
  labelFormatter: 'label'
});
  var defaultLabelFormatters = Validation.labelFormatters = {

Returns the attribute name with applying any formatting

    none: function(attrName) {
      return attrName;
    },

Converts attributeName or attribute_name to Attribute name

    sentenceCase: function(attrName) {
      return attrName.replace(/(?:^\w|[A-Z]|\b\w)/g, function(match, index) {
        return index === 0 ? match.toUpperCase() : ' ' + match.toLowerCase();
      }).replace(/_/g, ' ');
    },

Looks for a label configured on the model and returns it

 var Model = Backbone.Model.extend({
   validation: {
     someAttribute: {
       required: true
     }
   },

   labels: {
     someAttribute: 'Custom label'
   }
 });
    label: function(attrName, model) {
      return (model.labels && model.labels[attrName]) || defaultLabelFormatters.sentenceCase(attrName, model);
    }
  };

Built in validators

  var defaultValidators = Validation.validators = (function(){

Use native trim when defined

    var trim = String.prototype.trim ?
      function(text) {
        return text === null ? '' : String.prototype.trim.call(text);
      } :
      function(text) {
        var trimLeft = /^\s+/,
            trimRight = /\s+$/;

        return text === null ? '' : text.toString().replace(trimLeft, '').replace(trimRight, '');
      };

Determines whether or not a value is a number

    var isNumber = function(value){
      return _.isNumber(value) || (_.isString(value) && value.match(defaultPatterns.number));
    };

Determines whether or not a value is empty

    var hasValue = function(value) {
      return !(_.isNull(value) || _.isUndefined(value) || (_.isString(value) && trim(value) === '') || (_.isArray(value) && _.isEmpty(value)));
    };

    return {

Function validator Lets you implement a custom function used for validation

      fn: function(value, attr, fn, model, computed) {
        if(_.isString(fn)){
          fn = model[fn];
        }
        return fn.call(model, value, attr, computed);
      },

Required validator Validates if the attribute is required or not

      required: function(value, attr, required, model, computed) {
        var isRequired = _.isFunction(required) ? required.call(model, value, attr, computed) : required;
        if(!isRequired && !hasValue(value)) {
          return false; // overrides all other validators
        }
        if (isRequired && !hasValue(value)) {
          return this.format(defaultMessages.required, this.formatLabel(attr, model));
        }
      },

Acceptance validator Validates that something has to be accepted, e.g. terms of use true or 'true' are valid

      acceptance: function(value, attr, accept, model) {
        if(value !== 'true' && (!_.isBoolean(value) || value === false)) {
          return this.format(defaultMessages.acceptance, this.formatLabel(attr, model));
        }
      },

Min validator Validates that the value has to be a number and equal to or greater than the min value specified

      min: function(value, attr, minValue, model) {
        if (!isNumber(value) || value < minValue) {
          return this.format(defaultMessages.min, this.formatLabel(attr, model), minValue);
        }
      },

Max validator Validates that the value has to be a number and equal to or less than the max value specified

      max: function(value, attr, maxValue, model) {
        if (!isNumber(value) || value > maxValue) {
          return this.format(defaultMessages.max, this.formatLabel(attr, model), maxValue);
        }
      },

Range validator Validates that the value has to be a number and equal to or between the two numbers specified

      range: function(value, attr, range, model) {
        if(!isNumber(value) || value < range[0] || value > range[1]) {
          return this.format(defaultMessages.range, this.formatLabel(attr, model), range[0], range[1]);
        }
      },

Length validator Validates that the value has to be a string with length equal to the length value specified

      length: function(value, attr, length, model) {
        if (!hasValue(value) || trim(value).length !== length) {
          return this.format(defaultMessages.length, this.formatLabel(attr, model), length);
        }
      },

Min length validator Validates that the value has to be a string with length equal to or greater than the min length value specified

      minLength: function(value, attr, minLength, model) {
        if (!hasValue(value) || trim(value).length < minLength) {
          return this.format(defaultMessages.minLength, this.formatLabel(attr, model), minLength);
        }
      },

Max length validator Validates that the value has to be a string with length equal to or less than the max length value specified

      maxLength: function(value, attr, maxLength, model) {
        if (!hasValue(value) || trim(value).length > maxLength) {
          return this.format(defaultMessages.maxLength, this.formatLabel(attr, model), maxLength);
        }
      },

Range length validator Validates that the value has to be a string and equal to or between the two numbers specified

      rangeLength: function(value, attr, range, model) {
        if(!hasValue(value) || trim(value).length < range[0] || trim(value).length > range[1]) {
          return this.format(defaultMessages.rangeLength, this.formatLabel(attr, model), range[0], range[1]);
        }
      },

One of validator Validates that the value has to be equal to one of the elements in the specified array. Case sensitive matching

      oneOf: function(value, attr, values, model) {
        if(!_.include(values, value)){
          return this.format(defaultMessages.oneOf, this.formatLabel(attr, model), values.join(', '));
        }
      },

Equal to validator Validates that the value has to be equal to the value of the attribute with the name specified

      equalTo: function(value, attr, equalTo, model, computed) {
        if(value !== computed[equalTo]) {
          return this.format(defaultMessages.equalTo, this.formatLabel(attr, model), this.formatLabel(equalTo, model));
        }
      },

Pattern validator Validates that the value has to match the pattern specified. Can be a regular expression or the name of one of the built in patterns

      pattern: function(value, attr, pattern, model) {
        if (!hasValue(value) || !value.toString().match(defaultPatterns[pattern] || pattern)) {
          return this.format(defaultMessages.pattern, this.formatLabel(attr, model), pattern);
        }
      }
    };
  }());

  return Validation;
}(_));