The Ember Times - Issue No. 131

– By Chris Ng, Amy Lam, Isaac Lee, Jesse Jordan

Привет, Эмберисты! Hello, Emberistas! 🐹

Help improve Ember's autotracking and reactivity system 💬, read the new test waiters RFC ⏳, optimize your app with Ember Data 📈, the Russian Ember community 🇷🇺, and learn about powerful debugging at EmberConf 💻!


4 RFCs on improving Ember's autotracking and reactivity system 💬

Ember Octane features a new reactivity system thanks to tracked properties. They simplify syncing the DOM with JavaScript changes. Find out how autotracking works from the Ember Guides.

To help address some shortcomings, Chris Garrett (@pzuraq) proposed introducing the decorators and classes listed below. We encourage you to participate in RFCs and provide feedback!

566. @memo decorator

Unlike computed properties, autotracked getters don't cache their values. @memo will let you opt in to memoization.

567. @use decorator

The @use API will leverage autotracking to solve two issues:

  • Allow Glimmer components to define a behavior with its own lifecycle, independently of the template
  • Provide a standard way to mix declarative and imperative code

569. TrackedList class

TrackedList will autotrack changes to arrays. This class, designed to replace EmberArray, will follow the native array API closely and be performant.

577. TrackedMap and TrackedSet classes

TrackedMap and TrackedSet, along with their weak analogs, will autotrack changes to maps and sets (dynamic collections of values). These classes will follow the native APIs exactly.


New test waiters RFC ⏳

Steve Calvert (@scalvert) proposed replacing the existing test waiters with the ember-test-waiters in the New Test Waiters RFC.

The new test waiter system will provide a few benefits:

  • A new API that removes the existing foot guns given we will be more explicit when declaring the start and end of the waiter through the waiter beginAsync and endAsync methods
  • A more robust way to gather debugging information for the test waiter since the waiter is identifiable by the name provided
  • Default test waiters with the ability to author your own, more complex test waiters through annotating the asynchronous operations in your code base that are not tracked by an await settled() check

Share your thoughts, feedback, and requests on the New Test Waiters RFC!


Optimizing your app with Ember Data 📈

Chris Thoburn (@runspired) is blogging about how to build and optimize an app with Ember Data. You'll start by building an app, Listicle. Listicle starts as a small app shell with rich content lists, but balloons in size over time. Build times slow to a crawl as a result.

At the beginning of the series, Listicle builds and renders in greater than 5 seconds. But as the posts progress, you'll end with an app with builds and renders in less than 1 second by optimizing only the app's data management! Then for fun, you'll optimize the render.

You can check out Part 1 and Part 2 now, with more posts to come! And you can follow along with the code for the series by watching the Listicle repository.

For some Ember Data context, check out the Guides. You can learn about the architecture and history in Chris's EmberFest Ember Data 2019 conference talk.


Russian Ember community 🇷🇺

Habr.com is a popular geek media site among Russian developers. It's somewhat similar to Hacker News, except that it's populated by user-submitted articles instead of links. Iaroslav Popov (@chilicoder) recognized a shortage of Ember articles on Habr.com and recently started translating our very own Ember Times (Issue #129, Issue #130) on Habr.com, as well as Octane is Here and Super Rentals tutorial - Part 1!

@chilicoder also mentioned to check out the Ember telegram channel, moderated by Alex Kanunnikov (@lifeart). It's one of the best ways to get help with Ember in Russian, and they welcome everyone to join! Thank you both for your help in fostering the Russian Ember community!


Learn powerful debugging strategies at EmberConf 💻

You've undoubtedly heard her talk about creating progressive web applications with Ember and bulletproof addon testing before, but now Samanta de Barros (@sdebarros) is ready to share more useful knowledge that is crucial for any professional JavaScript developer.

At this year's EmberConf she's going to teach us about The Power of Debugging; which tools you can use to track down bugs swiftly in development and production environments, and how you can find your way around Ember's architecture while doing so.

In an exclusive interview with The Ember Times, Samanta shares with us, what makes debugging tools and strategies so powerful when developing Ember applications:

I think learning about debugging techniques is important. Mostly, because it will help you to have a better time finding bugs and even how an app works. In part I think it’s necessary because it will help you on your job!

I also think that when you start looking at other people’s code it is hard at first, but after a while you lose the fear of seeing these complex frameworks, you get a better idea of everything and you start to realise - it’s just JavaScript in the end. So I think debugging techniques are good for finding bugs and demystifying frameworks.

What's our experience like when we start to learn more about debugging strategies? Here, Samanta can share from both her own experience and from those she worked together with:

When you are pairing with someone or you’re trying to solve an issue, you often run into something and it makes people go like: “Oh, that’s interesting!” When I’ve seen other people’s talks or see them working, I see that they have some tips about things that I don’t know about yet and that’s cool! You realise that there are a lot of tools that make working with the frontend easier.

People who learn more about debugging usually say: “Oh yeah, that’s cool, that really simplifies these tasks I need to do” or “Oh, I didn’t know you could find that information there in the app.”

EmberConf is a unique experience, one that you and your team should definitely not miss out on. Samanta shares her perspective on what makes the conference so outstanding:

I think it’s a different experience when you go to a conference as a speaker or as attendee. When you just go to listen to the talks, you get a lot of inspiration, you discover things that people are you doing that you might not do yet and it sparks something in you that makes you want to learn something new or improve something in your job. […]

I would say both getting inspiration and connecting are the nicest things about EmberConf. If I had to recommend anything to an attendee, I’d say: “Just go and ask questions to the other attendees or speakers.” Just listening to the talks is good enough, but the chance to connect with others makes the conference really great.

If you want to learn more about successfully debugging Ember apps, join more than 800 other Ember developers at EmberConf in Portland, OR from March 16 - 18, 2020. Prices for regular attendee tickets start from $449, so don't hesitate to register today!


Contributors' Corner 👏

This week we'd like to thank @bobisjan, @pzuraq, @locks, @mjanjic01, @runspired, @igorT, @dmuneras, @mixonic, @chancancode, @nummi, @efx, @josemarluedke, @mansona, @pichfl, @skaterdav85, @jenweber, @mcfiredrill, @tomdale, @conormag, @rwjblue, @Turbo87, @stefanpenner, @xg-wang for their contributions to Ember and related repositories! 💖


Got a question? Ask Readers' Questions! 🤓

Office Hours Tomster Mascot

Wondering about something related to Ember, Ember Data, Glimmer, or addons in the Ember ecosystem, but don't know where to ask? Readers’ Questions are just for you!

Submit your own short and sweet question under bit.ly/ask-ember-core. And don’t worry, there are no silly questions, we appreciate them all - promise! 🤞


#embertimes 📰

Want to write for the Ember Times? Have a suggestion for next week's issue? Join us at #support-ember-times on the Ember Community Discord or ping us @embertimes on Twitter.

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That's another wrap! ✨

Be kind,

Chris Ng, Amy Lam, Isaac Lee, Jessica Jordan and the Learning Team