#

API Docs for: v3.8.1
Show: Inherited Protected Private Deprecated

# File: addon/-private/system/model/errors.js

    import { mapBy, not } from '@ember/object/computed';
    import Evented from '@ember/object/evented';
    import ArrayProxy from '@ember/array/proxy';
    import { set, get, computed } from '@ember/object';
    import { makeArray, A } from '@ember/array';

    /**
    @module ember-data
    */

    /**
      Holds validation errors for a given record, organized by attribute names.

      Every `DS.Model` has an `errors` property that is an instance of
      `DS.Errors`. This can be used to display validation error
      messages returned from the server when a `record.save()` rejects.

      For Example, if you had a `User` model that looked like this:

      ```app/models/user.js
      import DS from 'ember-data';

      export default DS.Model.extend({
        username: DS.attr('string'),
        email: DS.attr('string')
      });
      ```
      And you attempted to save a record that did not validate on the backend:

      ```javascript
      let user = store.createRecord('user', {
        username: 'tomster',
        email: 'invalidEmail'
      });
      user.save();
      ```

      Your backend would be expected to return an error response that described
      the problem, so that error messages can be generated on the app.

      API responses will be translated into instances of `DS.Errors` differently,
      depending on the specific combination of adapter and serializer used. You
      may want to check the documentation or the source code of the libraries
      that you are using, to know how they expect errors to be communicated.

      Errors can be displayed to the user by accessing their property name
      to get an array of all the error objects for that property. Each
      error object is a JavaScript object with two keys:

      - `message` A string containing the error message from the backend
      - `attribute` The name of the property associated with this error message

      ```handlebars
      <label>Username: {{input value=username}} </label>
      {{#each model.errors.username as |error|}}
        <div class="error">
          {{error.message}}
        </div>
      {{/each}}

      <label>Email: {{input value=email}} </label>
      {{#each model.errors.email as |error|}}
        <div class="error">
          {{error.message}}
        </div>
      {{/each}}
      ```

      You can also access the special `messages` property on the error
      object to get an array of all the error strings.

      ```handlebars
      {{#each model.errors.messages as |message|}}
        <div class="error">
          {{message}}
        </div>
      {{/each}}
      ```

      @class Errors
      @namespace DS
      @extends Ember.ArrayProxy
      @uses Ember.Evented
     */
    export default ArrayProxy.extend(Evented, {
      /**
        Register with target handler

        @method _registerHandlers
        @private
      */
      _registerHandlers(target, becameInvalid, becameValid) {
        this.on('becameInvalid', target, becameInvalid);
        this.on('becameValid', target, becameValid);
      },

      /**
        @property errorsByAttributeName
        @type {MapWithDefault}
        @private
      */
      errorsByAttributeName: computed(function() {
        return new Map();
      }),

      /**
        Returns errors for a given attribute

        ```javascript
        let user = store.createRecord('user', {
          username: 'tomster',
          email: 'invalidEmail'
        });
        user.save().catch(function(){
          user.get('errors').errorsFor('email'); // returns:
          // [{attribute: "email", message: "Doesn't look like a valid email."}]
        });
        ```

        @method errorsFor
        @param {String} attribute
        @return {Array}
      */
      errorsFor(attribute) {
        let map = get(this, 'errorsByAttributeName');

        if (!map.has(attribute)) {
          map.set(attribute, A());
        }

        return map.get(attribute);
      },

      /**
        An array containing all of the error messages for this
        record. This is useful for displaying all errors to the user.

        ```handlebars
        {{#each model.errors.messages as |message|}}
          <div class="error">
            {{message}}
          </div>
        {{/each}}
        ```

        @property messages
        @type {Array}
      */
      messages: mapBy('content', 'message'),

      /**
        @property content
        @type {Array}
        @private
      */
      content: computed(function() {
        return A();
      }),

      /**
        @method unknownProperty
        @private
      */
      unknownProperty(attribute) {
        let errors = this.errorsFor(attribute);
        if (errors.length === 0) {
          return undefined;
        }
        return errors;
      },

      /**
        Total number of errors.

        @property length
        @type {Number}
        @readOnly
      */

      /**
        @property isEmpty
        @type {Boolean}
        @readOnly
      */
      isEmpty: not('length').readOnly(),

      /**
       Manually adds errors to the record. This will triger the `becameInvalid` event/ lifecycle method on
        the record and transition the record into an `invalid` state.

       Example
       ```javascript
        let errors = get(user, 'errors');

        // add multiple errors
        errors.add('password', [
          'Must be at least 12 characters',
          'Must contain at least one symbol',
          'Cannot contain your name'
        ]);

        errors.errorsFor('password');
        // =>
        // [
        //   { attribute: 'password', message: 'Must be at least 12 characters' },
        //   { attribute: 'password', message: 'Must contain at least one symbol' },
        //   { attribute: 'password', message: 'Cannot contain your name' },
        // ]

        // add a single error
        errors.add('username', 'This field is required');

        errors.errorsFor('password');
        // =>
        // [
        //   { attribute: 'username', message: 'This field is required' },
        // ]
       ```
      @method add
      @param {string} attribute - the property name of an attribute or relationship
      @param {string[]|string} messages - an error message or array of error messages for the attribute
       */
      add(attribute, messages) {
        let wasEmpty = get(this, 'isEmpty');

        this._add(attribute, messages);

        if (wasEmpty && !get(this, 'isEmpty')) {
          this.trigger('becameInvalid');
        }
      },

      /**
        Adds error messages to a given attribute without sending event.

        @method _add
        @private
      */
      _add(attribute, messages) {
        messages = this._findOrCreateMessages(attribute, messages);
        this.addObjects(messages);

        this.errorsFor(attribute).addObjects(messages);

        this.notifyPropertyChange(attribute);
      },

      /**
        @method _findOrCreateMessages
        @private
      */
      _findOrCreateMessages(attribute, messages) {
        let errors = this.errorsFor(attribute);
        let messagesArray = makeArray(messages);
        let _messages = new Array(messagesArray.length);

        for (let i = 0; i < messagesArray.length; i++) {
          let message = messagesArray[i];
          let err = errors.findBy('message', message);
          if (err) {
            _messages[i] = err;
          } else {
            _messages[i] = {
              attribute: attribute,
              message: message,
            };
          }
        }

        return _messages;
      },

      /**
       Manually removes all errors for a given member from the record.
         This will transition the record into a `valid` state, and
        triggers the `becameValid` event and lifecycle method.

       Example:

       ```javascript
        let errors = get('user', errors);
        errors.add('phone', ['error-1', 'error-2']);

        errors.errorsFor('phone');
        // =>
        // [
        //   { attribute: 'phone', message: 'error-1' },
        //   { attribute: 'phone', message: 'error-2' },
        // ]

        errors.remove('phone');

        errors.errorsFor('phone');
        // => undefined
       ```
       @method remove
       @param {string} member - the property name of an attribute or relationship
       */
      remove(attribute) {
        if (get(this, 'isEmpty')) {
          return;
        }

        this._remove(attribute);

        if (get(this, 'isEmpty')) {
          this.trigger('becameValid');
        }
      },

      /**
        Removes all error messages from the given attribute without sending event.

        @method _remove
        @private
      */
      _remove(attribute) {
        if (get(this, 'isEmpty')) {
          return;
        }

        let content = this.rejectBy('attribute', attribute);
        set(this, 'content', content);
        get(this, 'errorsByAttributeName').delete(attribute);

        this.notifyPropertyChange(attribute);
        this.notifyPropertyChange('length');
      },

      /**
       Manually clears all errors for the record.
         This will transition the record into a `valid` state, and
         will trigger the `becameValid` event and lifecycle method.

      Example:

       ```javascript
       let errors = get('user', errors);
       errors.add('username', ['error-a']);
       errors.add('phone', ['error-1', 'error-2']);

       errors.errorsFor('username');
       // =>
       // [
       //   { attribute: 'username', message: 'error-a' },
       // ]

       errors.errorsFor('phone');
       // =>
       // [
       //   { attribute: 'phone', message: 'error-1' },
       //   { attribute: 'phone', message: 'error-2' },
       // ]

       errors.clear();

       errors.errorsFor('username');
       // => undefined

       errors.errorsFor('phone');
       // => undefined

       errors.get('messages')
       // => []
       ```
       @method remove
       */
      clear() {
        if (get(this, 'isEmpty')) {
          return;
        }

        this._clear();
        this.trigger('becameValid');
      },

      /**
        Removes all error messages.
        to the record.

        @method _clear
        @private
      */
      _clear() {
        if (get(this, 'isEmpty')) {
          return;
        }

        let errorsByAttributeName = get(this, 'errorsByAttributeName');
        let attributes = [];

        errorsByAttributeName.forEach(function(_, attribute) {
          attributes.push(attribute);
        });

        errorsByAttributeName.clear();
        attributes.forEach(attribute => {
          this.notifyPropertyChange(attribute);
        });

        ArrayProxy.prototype.clear.call(this);
      },

      /**
        Checks if there are error messages for the given attribute.

        ```app/routes/user/edit.js
        import Route from '@ember/routing/route';

        export default Route.extend({
          actions: {
            save: function(user) {
              if (user.get('errors').has('email')) {
                return alert('Please update your email before attempting to save.');
              }
              user.save();
            }
          }
        });
        ```

        @method has
        @param {String} attribute
        @return {Boolean} true if there some errors on given attribute
      */
      has(attribute) {
        return this.errorsFor(attribute).length > 0;
      },
    });