Notes from the 'Ember Data Talk' session

Speaker

Igor Terzic

• Twitter profile
• Lanyrd profile
• Github profile

Intro

• Why can't I call commit ona model
• Why can't I reorder elements in a many array
• Why can't I rollback a single model

Plot

• Try doing simple thinggs
• Fail
• Uncover some ember-data functionality to help us
• Framework authors are not clowns writing code.

Meet our Models: App.Post and App.Comment

App.Post = DS.Model.extend({
  title : DS.attr('string');
});

What do we want to happen?

• Comment.get('post') is set correctly

• Comment and post are dirtied correctly

  var oldParent = store.find(App.Post, 1), newParent = store.find(App.Post, 2)

What do we expect to happen?

• post1.get('comments') doesn't contain comment
• Objects are dirtied correctly

It is 2013

• People have solved this before
• ActiveRecord, Django, etc

Ember data is more complex than traditional ORM. It's more complex to use Ember-data because you don't know how your objects will be stored.

Ember-data to the rescue

• one to one
• one to many
• many to many
• ... more

Encode our own constraints

• Cannot be empty
• Can't have more than 4 elements

if you modify data.

What to send to the server?

• It depends
• Rails adapter - saved on the child
• node.js and mongo - saved on the parent
• If embedded need to go up the chain

Other gotchas

Because Ember-data has to work with so many apis there are other gotchas

• Transactions
• HasMany is not really an array

There are plenty of issues where I tried to so something that should be simple but after working it through for an hour or two it totally blows up. Trying to work within Ember-data conventions and not fighting it totally helped my sanity.

Future

• isDirty and shouldCommit
• applyingChanges to the future

Published

Tags

• emberjs 18
• embercamp 10