Ember best practices

Ember best practices.md

Ember best practices

DDAU (Data Down, Actions Up)

• http://emberjs.com/blog/2015/05/10/run-up-to-two-oh.html#toc_new-lifecycle-hooks
• In future, with angle bracket components one-way binding will be the dafault
• Makes it easier to reason about code
• (mut) helper for setting values from action

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• Should we allow data fetching in our components?
• Are simple input-fields allowed to use two-way binding?

Observers/Computeds

• https://www.youtube.com/watch?v=7PUX27RKCq0
• Eager vs. lazy
• Possibility for intermediate invalid state
• Observers only really needed when dealing with external libs like D3
• Makes it easier to reason about code

didReceiveAttrs

• http://emberjs.com/blog/2015/06/12/ember-1-13-0-released.html#toc_component-lifecycle-hooks
• Use didReceiveAttrs to react to change in data instead of observers

Closure actions

• https://ember-twiddle.com/39e20372b90ec23fa27d

Functions instead of strings

• https://ember-twiddle.com/2c4ffc7969d1ad32986c

Return values (no more returning false to stop bubbling)

• https://ember-twiddle.com/1b23569ea0228e12d9d2
• Requires attrs, not sendAction
• http://locks.svbtle.com/to-attrs-or-not-to-attrs

Multiple sources in route model

• Now we usually load the main data in model hook, and the rest in setupController
• -> leads to weird states, and application not be fully usable before all promises have resolved

Ember.RSVP.hash to the rescue

• Use Ember.RSVP.hash to collect all promises in model hook
• Example: https://github.com/ecraft/systemair-tech-data/tree/master/src/routes/item

Loading/Error substate

Ember.Data

Define type of DS.attr

• Problem in Altus offline -> non-evident datatype because of storage
• Serves as documentation

Define inverse relationship on models

• Problem in Altus offline/IL