Ember data duplicate records fix

adapters.application.js

import DS from 'ember-data';

export default DS.RESTAdapter;

application.controller.js

import Ember from 'ember';

const equal = function(a, b, desc = '') {
  return Ember.assert(desc, a === b);
}

export default Ember.Controller.extend({
  appName:'Ember Data duplicate records fix',
  isSaving: false,
  actions: {
    save() {
      this.set('isSaving', true);
      
			let store = this.get('store');
      Ember.run(function() {
        store.unloadAll('foo');
        store.unloadAll('bar');
        store.unloadAll('baz');
      });
      
			let foo  = store.createRecord('foo', { name: 'foo 1' });
			let bar1 = store.createRecord('bar', { name: 'bar 1' });
			let bar2 = store.createRecord('bar', { name: 'bar 2' });
			let baz1 = store.createRecord('baz', { name: 'baz 1' });
      
      foo.get('bars').pushObject(bar1);
      foo.get('bars').pushObject(bar2);
			foo.set('baz', baz1);
      
      equal(foo.get('name'), 'foo 1', 'foo model exists');
      equal(foo.get('bars').objectAt(0).get('name'), 'bar 1', 'foo has many bars');
      equal(foo.get('bars').objectAt(1).get('name'), 'bar 2', 'foo has many bars');
      equal(foo.get('baz.name'), 'baz 1', 'foo has one baz');
      equal(store.peekAll('bar').get('length'), 2, 'store knows about bars');
      equal(store.peekAll('baz').get('length'), 1, 'store knows about baz');
      
      foo.save().then(() => {
        equal(foo.get('name'), 'foo 1 (saved)', 'foo model is updated');
        equal(foo.get('bars').objectAt(0).get('name'), 'bar 1 (saved)', 'hasMany is updated');
        equal(foo.get('bars').objectAt(1).get('name'), 'bar 2 (saved)', 'hasMany is updated');
        equal(foo.get('baz.name'), 'baz 1 (saved)', 'belongsTo is updated');
        equal(store.peekAll('bar').get('length'), 2, 'duplicate hasMany records are cleaned up');
        equal(store.peekAll('baz').get('length'), 1, 'duplicate belongsTo records are cleaned up');
        
        this.set('isSaving', false);
      })
    }
  }
});

application.template.hbs

{{#if isSaving}}
  Saving...
{{else}}
	<button {{action 'save'}}>Save</button>
{{/if}}

aREADME.txt

This twiddle demonstrates a fix for this issue:

"Ember Data creates duplicate records"
https://github.com/emberjs/data/issues/1829

See models/foo.js #save for the fix
See application/controller.js #save for the tests

View the console for a list of hasMany and belongsTo records that are cleaned up.

models.bar.js

import DS from 'ember-data';

export default DS.Model.extend({
  name: DS.attr('string')
});

models.baz.js

import DS from 'ember-data';

export default DS.Model.extend({
  name: DS.attr('string')
});

models.foo.js

import DS from 'ember-data';

export default DS.Model.extend({
  name: DS.attr('string'),
  bars: DS.hasMany('bar', { async: false }),
  baz:  DS.belongsTo('baz', { async: false }),
  
  save: function() {
    let recordsToDelete = [];
    
    let cleanup = function(record) {
      if (record && record.get('isNew')) {
        recordsToDelete.push(record);
      }
    };
    
    this.eachRelationship((name, descriptor) => {
      if (descriptor.options.async) { return; }

      if (descriptor.kind === 'hasMany') {
        this.get(name).forEach(cleanup);
      } else if (descriptor.kind === 'belongsTo') {
        cleanup(this.get(name))
      };
    });

    let promise = this._super();
    
    console.log('Cleaning up', JSON.stringify(recordsToDelete));

    promise.then(() => {
			recordsToDelete.forEach((record) => {
        Ember.run(function() {
          let relationships = record._internalModel._implicitRelationships;
          Object.keys(relationships).forEach((name) => delete relationships[name]);
          record.deleteRecord();
        });
      });
    });
      
    return promise;
  }
});

serializers.application.js

import DS from 'ember-data';

export default DS.RESTSerializer;

serializers.foo.js

import DS from 'ember-data';

jQuery.mockjax({
  url: '/foos',
  type: 'POST',
  responseText: {
    foo: {
      id: 1,
      name: 'foo 1 (saved)',
    	bars: [
        { id: 1, name: 'bar 1 (saved)' },
        { id: 2, name: 'bar 2 (saved)' }
      ],
      baz: {
        id: 1,
        name: 'baz 1 (saved)'
			}
		}
  }
});

export default DS.RESTSerializer.extend(DS.EmbeddedRecordsMixin, {
  attrs: {
    bars: {
      embedded: 'always'
    },
    baz: {
      embedded: 'always'
    }
  }
});

twiddle.json

{
  "version": "0.4.11",
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.0.0/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.0.0-beta.2/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.0.0/ember-template-compiler.js",
    "jquery-mockjax": "https://cdnjs.cloudflare.com/ajax/libs/jquery-mockjax/1.6.2/jquery.mockjax.js"
  }
}