069: Redux Part II with Toran Billups

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podcast

Ember

Toran Billups @toranb | GitHub | Blog

Show Notes:

01:44 - New Developments in ember-redux
04:23 - New Developments in the Wider Redux Community
06:26 - Using Redux in Ember
09:40 - Omit
10:45 - Reducers
25:42 - Fulfilling the Role of Middleware in Ember
28:12 - Ember Data in Redux-land
31:24 - What does Toran do with this stuff??

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Transcript

CHARLES: Hello everybody and welcome to The Frontside Podcast, Episode 69. My name is Charles Lowell. I'm a developer here at The Frontside and your podcast host-in-training. With me Wil Wilsman, also a developer here at The Frontside. Hello, Wil.

WIL: Hello.

CHARLES: Today, we have a special guest, an actual elite member of the three-timers club, counting this appearance. We have with us Toran Billups. Thank you for coming on to the show today.

TORAN: Absolutely. I'm not sure how the third time happened but I'll take it.

CHARLES: Well, this is going to be the second one, we're going to be talking about Redux and then I believe you're on the podcast back in 2014 or 2015.

TORAN: That's right.

CHARLES: That's one of our first episodes. Make sure to get in touch with our producer afterwards to pick up your commemorative mug and sunglasses to celebrate your third time on the show. Awesome. I'm glad to have you. We actually tend to have people back who are good podcast guests.

TORAN: Thank you.

CHARLES: Yeah, I'm looking forward to this one. This is actually a continuation of a podcast that we did back in January that was actually one of our more popular episodes. There was a big demand to do a second part of it. That podcast we talked about the ember-redux library, which you're a maintainer and just kind of working with Redux in Ember in general. We’re going to continue where we left off with that but obviously, that was what? Almost six months ago? I was wondering maybe you can start there and there been any kind of new developments, exciting things, what’s kind of the state of the state or the state of the reducer or the state of the store in ember-redux.

TORAN: For ember-redux, in particular, we're working on three initiatives right now. The first is making the store creation more customizable. A lot of people that come from the React background in particular are very used to hand crafting how the stores put the other with the right middleware and enhancers and reducers and that's been fine. I wanted to drop people into the pit of success and everybody's cool with that but now we're getting to a point where there are people wanted to do different things and it's great to open the door for those people if they can, while keeping it very simple so we're working on that. We have here that's just undergoing some discussion.

We’re also, just as the wider Ember community -- you guys maybe involved in this as well -- and trying to get the entire stack over to Babel 6, the ember-cli Babel 6.10 plus stack. There is a breaking change between Babel 5 and 6 so we're also having some discussions about the ember-redux 3.0 version bump at some point later this year, just because we really can't adopt this without introducing basically a breaking change for older ember-cli users.

CHARLES: Just in general, this is a little bit off topic, what does it mean to go from Babel 5 to Babel 6, if I'm an add-on author.

TORAN: I would probably ensure that need to speak more with Robert Jackson about this. We just kind went back and forth because I thought I had a Babel compile error. He’s like, "No, you're missing this dependency which is the object spread." Unfortunately, the object spread is rampant in React projects and this is totally cool. I had to actually add that and that's just a breaking difference between these two. If we adapt the new version of this in the shims underneath of it as an Ember 2.43 user, if you're on node four which is still supported, you will break without this.

I'm trying to get some discussion going about what we should do here and if we even should push ahead and just say only node six is supported. There’s some discussion and then back to your original question, the third piece is we've introduced the ability to replace the reducer but we need to get some examples for hot reloading the reducer. That’s a separate project but it needs to be enabled by ember-redux. Those are the three main initiatives.

CHARLES: Being able to you hot load your reducers, just to make changes to your reducer and you just thunk them into the application without having to lose any of the application state and that one of the reasons that's possible then is because you're reducers have no state themselves. They’re just pure functions, right?

TORAN: Exactly.

CHARLES: Okay. Awesome. That sounds like there's a lot of cool stuff going on. Beyond ember-redux, are there any developments to look for on the horizon in the wider Redux community that might be coming to Ember soon?

TORAN: Actually one of them is actually fairly new and it's already in Ember and just because I have already got a shim up for it is redux-offline, which I remember you had Alex on two episodes ago about breaking your brain around Rx. I feel like that happened for me trying to build apps offline first. This is, of course just another library that can drop in that place nicely with Redux but I feel like the community, at least it's got me thinking now about what an absolute that would really disrupt someone who's a big player today. I feel like you've built a great offline experience with true and well done data syncing. You could really step in and wreck someone who's in the space today.

CHARLES: Right, so this is a sim around... what was the name of the library again?

TORAN: Redux-offline.

CHARLES: Okay, so it's just tooling for taking your store and making sure that you can work with your store if you're not actually connected to the network and like persisting your store across sessions?

TORAN: Yeah. It uses a library that called redux-persist that takes care of and kind of hydrating the store if you have no network connectivity. But it's also beginning to apply some conventional pattern around how to retry and how to roll back. It’s just an interesting look at the offline problem through the lens of an action-based immutable data flow story. It’s interesting. I don't have a ton of experience with that kind of tweet and rewrote my Yelp clone with it and that was tough. That’s what I mean by this. It’s like I thought this is very trivial but you have to do a lot of optimistic rendering and then sort of optimistically gen primary keys that gets swapped out later and it's tricky.

If you've never done offline first, which I have not, I just think offline is pretty cool and along those lines, there's been a lot of discussion around convention. There’s of course, Create React app which is like a little library or CLI tool to kick off your Redux in React projects. It's kind of ember-cli, very trimmed down version of that right now and that's just getting incrementally better. Of course, you guys are in the React space so you may touch upon that story if you haven't already.

CHARLES: All right. We talked to the very high level, I think the last time we had you on the show but now that the idea is gaining traction, kind of delve into more specifics about how you use Redux in Ember. I asked at the end of the last podcast, let's step through a use case like what would deleting an item look like in ember-redux land. Maybe we could pick that up right now and just understand how it all connects together.

TORAN: Yeah, absolutely. Without understanding how this entire flow or this event bubbling happens is hard to get your head around it. The process we're going to walk through is exactly that use case you laid out, Charles. We’re going to have a button in our component and that button, on-click the idea is to remove an item in a list that we happen to be rendering, let's say.

If this is a child component like the very primitive literally button that you have and you just have your on-click equal probably a closure action in Ember, the parent component or the outer context is going to be responsible for providing the implementation details for this closure action and what it does. This is kind of the meat of what you're getting at. The high level here is there is a single method on the Redux store that you have access to and it is called dispatch. The nice thing about Redux again, the API surface area is very small. It’s just a very handful of methods you need to get your head around.

This one, in particular takes one parameter, this dispatch method. That parameter is a JavaScript object. Now, if you're just playing around, you just want to see the event flow up, there's only one requirement asked of you and that is type property. This JavaScript objects have a type that is often a string so it's very human friendly, you just put in there and the string remove item, let's say.

Now of course, if you want to remove a particular item in this remove example, you of course want to pass some information as well beyond the type. The type is mostly just a Redux thing to help us identify it but in this case, you'll definitely know the primary key or the ID value, let's say of the item you want to remove. In addition to type, this JavaScript object, let's just say has an ID property and that can come up from the closure action somehow if you want. Once you click this, what's going to happen is you're going to fire this closure action, the closure action is going to invoke dispatch with the JavaScript object and dispatch is going to run through the reducer which is the very next step and what we do is we take the existing state. Let’s say we have a list of three items, that's going to be the first argument now in the reducer.

The second argument is this action which is just, as I describe it a JavaScript object with two properties: type and ID. You can imagine an ‘if’ statement, conditional switch statement that says, "Is this the remove item action? If it is, okay." We had the ID of the item that want to remove and since we have a dictionary where the primary key of the item is the ID, we can just use lodash-omit and we basically use omit to filter out the ID and then use object assigned to a transform or produce a new state and then a callback occurs after this that tells your list component that somewhere in your Ember tree to re-render, now only showing two items.

CHARLES: One of the things I want to point out there, you just touched on it but I think it's an interesting in the subtle point is that the lodash method that you used was omit and that's how this is kind of tangential or I'll say parallel to programming in this way is that you don't actually use methods that mutate any state. You calculate new states based on the old states. I think that's a great example of that -- that omit function -- omission is the way that you delete from something in an immutable fashion. You’re actually filtering or you're returning a new copy of that dictionary that just doesn't have that entry. You’re just a omitting it. You’re not destroying the old one. You’re not deleting anything. You’re not changing it. You’re just kind of Xeroxing it but without that one particular entry, which is ironic because the effect on the UI is that you have done a delete but really what you're doing is omitting there.

I just think that's cool. I think it's one of the ways that using the systems teaches you to think about identity differently. Then the question I want to ask you was, this all happens in the reducer, what does that mean? Was that word mean -- reducer? I kind of like danced around that idea and I've tried to understand where that term came from and how it helps give insight into what it's doing and I come up short a lot. Maybe we can try and if we can't explain what the name of reducers, maybe there's some alternate term that we can help come up with to aid people's understanding of what is the responsibility of this thing?

TORAN: Yeah, I think we can just break down reduce first then we'll talk about how it ends up looking. But I think it's reduced almost like it's defined in the array context. If I have an array of one, two and three and I invoke the reduce method on that, we actually just produced a single value, sort of flatten it out and produce a single value as the result to that, so three plus two plus one, six is the end result.

What we've glossed over this entire time, probably last episode is that this reduce word, I believe is used because in Redux, we don't really just have one massive monolithic reducer for the entire state tree. We instead have many small reducers that are truly combined to do all the work across the tree. In my mind is I think reducer fits well here because we're actually going to combine all these reducers and they're all going to work on some small part of the state tree. But at the end of the day, we still have just one global add-on and that's the output. We want one global add-on with a new transform state and that is the reduced state.

CHARLES: You take some set of arguments. One of which is the prior state and you reduce that into a single object. I like that. The other place where I've seen this term applied in a similar context is in Erlang. They talk about reduction so that you have an Erlang server where the way that the servers modeled is as a recursive function call where you pass in the prior state of the server plus any arguments if you're handling a request or something like that, bundled in there is going to be arguments of the request and then what that function returns is a new state, which is then used to pass in to the next state. They call this process reduction.

We’ve got two data points. Maybe there, we can go search for the mathematical foundation of that later --

TORAN: I like it.

CHARLES: -- if you want to geek out. I think that helps a lot. Essentially, to sum up the responsibility of the action is you take a set of arguments, it's going to take the existing state of the store, run it through your reducers and then it's going to set the next state of the store or yield the next state of the store. Is that a fair summary of what you would say the responsibility action is?

TORAN: Yeah. I think you're right. In fact, in preparation for this talk, I just threw together really small Ember Twiddle that will link in a show notes what I call the mega trimmed down version of ember-redux. It’s basically a really naive look but for conceptualizing this flow, it's about 24 lines of code that show exactly what you're saying which is I have this reducer, it's passed into this create store method in the syntax, how do this actually look? It better illustrates how the reducer is used when dispatch is invoked so a dispatch, if I was actually to walk line by line through this, which will be probably pretty terrible. But the very first line of dispatch is to just call the reducer.

From that new state transformation, we just push in so the store gets a new entry into it's array of here's the next state and because we had never tampered or side effect-ted the old state, we could easily go back in time just by flipping the pointer in the array or that indexing the array back point.

CHARLES: I guess my next question is we've talked a little bit about immutability and we know this reducer that we call at the very first point of the dispatch is a pure function. You were dealing with pure functions, immutable data but at least in perception for our users, our system is going to have a side effect. There’s going to be calls to the network. We are, in the least in theory deleting something from that list. How do you go about modeling those side effects inside Redux?

TORAN: This is a great intro because in fact a friend of mine is actually a teacher at a boot camp and he was telling me the other day that he was asked to do a brief look at Redux and his very first feeling when he was watching some of the Egghead.io videos is like, "Oh, so the reducer is pure but I have to side effects something so where do I do this?" It's not very clear, I think for the very beginner which is why we left it out of that part one podcast. Today, we're kind of hit that head on but before we get into that list, we can talk about what having actions in their simplest form look like today in your Ember app.

As I mentioned earlier in this remove example, you got the button, it just takes the closure action the on-click. No big deal. The bigger work was on the parent contexts or the parent component to provide this action, which sounded very simple but imagine instead of just dispatching synchronously, which is we talked through. Imagine we only wants to dispatch that officially to change it if we have gotten a 204 back and the fetch request is deleted on the server -- normal Ajax or fetch-type flow.

In this case, you start to add a little more code and imagine for the moment this is all inline in your component JS file. The component now is started to take on an additional responsibility. In addition to just providing a simple dispatch, as I say, "Go and remove this Mr Reducer later," you're now starting to put some asynchronous logic and as you imagine a real application, you grows and try catch stuff, some error handling, some loading, some modals. This gets out of hand.

One of the things that I want to touch on briefly is, at least in the ember-redux case we ship this Promise-based middleware and I want to stop right there for just a second because I use that word 'middleware' and immediately we've got at least highlight what this is doing. In that pipeline -- we talked about earlier -- in the component I dispatch and it just goes right to the reducer. Well, technically there's actually a step or an extension point right before the reducer is involved and that is where middleware comes in. Technically, you could dispatch from this action and then you could handle and do the network IO type request in middleware instead, then porting on another dispatch of a different type with the final arguments to be transformed. That’s really the role.

CHARLES: Can middleware actually dispatch its own actions?

TORAN: Correct, yep. In fact, one of the first big differences between this example as I'm kind of hacking around the component and I've got access to dispatch but there's two things I'm really actually lacking if I don't leverage middleware full on. The first is I do have some state in the component but often, it's actually just a very small slice of state that this component renders. If there's actually a little bit more information I need or actually need to tap into the full store, I don't have it and that might be considered a good constraint for most people.

But there are times you imagine more complex apps, you need the store. You might even see a little bit more state, middleware provides that is where you trapped with just that slice of state and dispatch the keyword. That’s about it in the component. But the other side effects are the benefit, as you break this out is you get another seam in the application where the component now is not involved with error handling and Promises and async flows or generators. It just does the basic closure action set up and fires dispatch almost synchronously like you did in our very simple example, allowing the middleware to actually step in and play the role of, "Okay, I'm going to do a fetch request and I'm going to use a generator." It's almost like the buffer for IO or asynchronous work that it was missing in our original equation.

Imagine, you want to debounce something or you want to log something or you want to cancel a Promise, which you can't do, any of that stuff that's going to happen in this middleware component. That's one of the things I like about middleware as I learn more about it and the moment you get to a very complex async task where you're actually doing the typical type ahead, where you literally want to cancel and not do the JavaScript work or you like to cancel the Promise as quickly as you can, you can very quickly dive into something kind of like what you and Alex talk about with ember-currency in the Redux-land. It’s called redux-saga. It's just a generator-based async work.

CHARLES: Is saga kind of emerged as async library that everybody uses? I know it's very popular.

TORAN: Yeah and a good reason, I mean it solves a lot of the problems that if you were to try and do the cancelation token Promise stuff that came out a while back where we're trying to figure out how to cancel Promises. There's a lot more ceremony and just a lot more state tracking on your own that generators and even when I played with this last week, which is actually redux-observable which is an Rx-based middleware. It's built by, I think Ben Lesh and Jay Phelps from Netflix or... sorry, Jay is still at Netflix but anyway...

You could use Rx, you could use generators. This really is just the escape valve for async and complex side effect programming that can't or shouldn't take place in the reducer because it's pure. It shouldn't take place necessarily in a component because one of the best pieces of advice I got when I was younger was, " Toran, make sure you do or delegate," and we're talking really about levels of depth in your methods at the simplest. But it applies here as well, which is I would love it if I had just a very declarative component and I didn't have to get into the weeds as I was looking at it about, is this a Promise? Is this Redux thunk, as they call it? Is this a generator or is it Rx? I don't even care in the component for the most part. I just need to know the name of the action and the arguments. If I'm having a problem with the Rx side of the generator, I'll go into the middleware and work from that particular abstraction but you can see the benefits of the seam there.

CHARLES: Are the middlewares match on the action payload in the same way that the reducers do? Is that fair to say?

TORAN: That is fair and I will warn. If that seems very strange, you're probably not alone. In fact, the first time I did this with redux-saga, I was dispatching, only to turn around then dispatch again. It feels very strange the first time but again, keeping in mind that you're really trying to have a separation from the work that is side effect and the work that is pure. The first action in that scenario, we'll call it remove-saga because it's actually going to fire something to a middleware. That work is all going to be network-heavy and it's not really as easily undo-redo because it's not pure.

But the second event invoked from the actual middleware itself that says, "Remove item. Here's the ID. We're good." That work could be undone-redone all day because it hits the reducer, which is sure you can in and out.

CHARLES: It sounds like basically the middleware is allowing you to have a branching flow structure because they all do involve more actions getting dispatched back to the store to record any bookkeeping that needs to happen as part of that. If you want to set some spinner state, that will be an action that gets dispatched. But in terms of sync, they allow you to set up sequences of actions or if you basically have one action that will actually get resolved as ten actions or something like that.

If you think about an asynchronous process, you have the action that starts it but that might end up being composed of five different actions, right? Like I want to set the application into some state that knows that I've started my delete and that means I want to show like the spinner. Then at some later point, I might want to show progress like this deletes really taking a long time and I might want to dispatch five different actions indicating each one of those little bits of progress. Then finally, I might want to say it's done or it fails so really those got decomposed into 10 actions or five actions or whatever so the middleware is really where you do that, where you decompose high level actions into smaller actions? Or it's one of the places? Is that a correct understanding?

TORAN: Yeah, I think if you're an old school developer for a minute, it will cater to the audience that maybe came from early 2000s backend dev. Now, they're still pretty current in web dev. I see it talked about as business logic. I feel like this is really the bulk of the complex work, especially if you're using Rx. You're actually creating these declarative pipelines for the events to flow through. My components are much thinner by comparison. They're truly just fire off this action with the information to kick the async pipeline but in the async piece of it, there's a lot more work happening and that's I think because there's a lot of complexity in async programming.

CHARLES: Right, and it's almost like with the reducers then, there's not so much business logic because you're just resolving the implications of the new state. Is that fair to say? It’s like now we've got this information, what does this imply directly?

TORAN: Yeah, I think there is this old [inaudible] thing where they're talking about what's should be thick. You know, thick controllers or thick models, what should it be? Of course, we never want 'thick' anything, is the right answer, I think. But the apps on building today, I feel like if any was thick-er -- a measure of degree bigger in effort or work -- it is these middleware components right now.

I think the nature of what you describe, which is the reducer is not supposed to be doing anything complex. It's literally taking a piece of data in, producing a new piece of data out. Logically thinking about that takes much less effort, I think than the human brain applies to async programming in JavaScript.

CHARLES: Right. I think it makes sense and some of these things are just going to be necessarily gnarly and hairy because that's where the system is coupled. I can't say anything about whether the delete succeeded or failed until I've actually fired off the request. Those are implicitly sequenced. There has to be some glue or some code declaring that those things are sequenced. That has to be specified somewhere, whereas theoretically with your reducers, you could just run them all in parallel, even. If JavaScript supported multithreading, there's absolutely no dependency between those bits of code.

TORAN: I think so, yeah. I think there are still some challenges because in the reducer sometimes. We can talk about this in a few minutes but you may actually be changing several top level pieces of the tree. If you're de-normalizing, which is what we probably should touch on next, there are some cases where you want to be a little careful but like you said, generically immutable programming enables multithreading. We’re not touching the same piece of state at same time.

CHARLES: Right as long as that piece of state that you're touching, like you need to resolve the leaf nodes of the tree first but at any siblings, I guess is what I'm saying on there, ought to be able to be resolved in parallel. It's more an exercise in theory or just a way of thinking about it because like why you're able to do those reducers as kind of these pure functions is because there's no dependency between them.
I guess I'm just trying to point out that to wrap my head around, there are places where there are just clear sequences and dependencies and those are things that would be in the middleware.

TORAN: Gotcha. I came a little scared of service worker.

[Laughter]

CHARLES: Actually a great point is what kind is the analogous -- if there is anything analogous -- in Ember today that's fulfilling the role of middleware. What’s the migration path? What’s the alternative, just trying to explore like where you might be able to use these techniques that we've been describing inside your app?

TORAN: I think, at least my look at it has been a service injected into a service, which sounds completely bad or sounds broken the first time you see because you're like, "We're injecting a service into an existing service." I say that because, for me at least there is a top level service that owns the data and provides read-only attributes but there should be some other piece of code -- not the component -- that is doing this asynchronous complex processing, we just talk about as middleware, that is often a different service than the service that owns the state add-on. That's what I meant by service-injected.

There’s some Ember service whose job is to manage the complexity and probably ended up in middleware from the Redux perspective or ember-concurrency is literally solving that in my opinion. They do a lot for you: solving the async problem generally and I haven't dug into ember-concurrency enough to know. The pipeline stuff, I think which you guys talked about, which is an RFC, that may have eventually be what I consider the Rx or redux-saga of the middleware today.

CHARLES: Right. I think ember-concurrency is just absolutely fantastic but it is a hairy problem but there's some overlap in terms of what it is solving. I think that is interesting. I guess a case where you would use middleware would be anywhere that you would use ember-concurrency. I think the interesting thing to compare in contrast there is one of maybe advantages or disadvantages -- let's just call it a tradeoff -- is that with ember-concurrency, you have this middleware that is associated with an object. It's associated usually with a component or a route.

When things happen to that component, you're able to affect your ember-concurrency process but it does mean, these things are sprinkles throughout your application and the rules that are governing them can be really different, depending on which part you're operating in or just because sometimes you're using them on a route. Sometimes, you're doing it on a component. Sometimes, you're doing it on a service, whereas with the putting in the middleware, it sounds like they're going to all be in one particular place.

All right. Let’s move on from the simple to the more complex because that's where it's at. We've talked about modeling async processes, we've talked about handling state transitions and all that, nothing typifies that more profoundly in Ember community than Ember Data as just a foundation for state and syncing it over to the network. Love it or hate it, it's very popular. What are the things that you do in ember-redux land? One, is it fundamentally incompatible with Ember Data or is it just more easily served with other alternatives? How do you handle those foundational interactions, those fun foundational async loading network interactions with Ember Data, just using an ember-redux?

TORAN: Yeah, for myself, I don't have an experience actually using the two together on purpose. There is a gentleman who did a talk sometime last year and I'll dig up the YouTube clip for you guys, where he talked about his approach where you would actually produce new states so it's still Redux friendly. Ember Data itself just be a new Ember Data model, every time you transformed it. But one of the tricky points is the philosophy of both so in Ember Data, you're just invoking set on everything and not just how it works. That's how the events bubble through the system as you re-render. You never actually create a new state of the system that's a copy, minus or plus, other attributes. You just always touching a single source of truth. I felt like that was always a sticking point.

Anyway, Thomas who did this talk and I'll point you guys to it, did a great job of saying like, "Look, if you're stuck in this world with a lot of Ember Data, you're having some pain points with it and you want to try Redux to see if this alleviates those by not changing the state, here is a middle ground," which he did, I think a fabulous job driving it out. Although I must admit, there's got to be some challenges in there just because of the philosophical difference between the two.

CHARLES: Yeah. It definitely sounds like there's some challenges but I'm actually pretty eager to go and watch that, to see what they came up with. If you're using these snapshot states of your Ember objects, would it be possible then to take all of your save, delete records, even query and have them inside of middlewares like have a redux-saga for every single operation you want to take on the Ember Data store.

TORAN: The example he showed is basically the best of both worlds. You don't want to ember-mutate so he has a special bit of code to do that. But because the rest of it is vanilla Ember, you could drop in concurrency if you want to do the saga-type generator stuff. But you could also just make your changes as you would otherwise. You use the adapters, you fetch, you save, you delete, whatever you want to do for the most part. It saves a lot on the de-normalized side, which you would have to do manually. You don't write any Ajax code, which you have to do manually on the Redux side. I think there are benefits if someone could get it to work where you're just not changing the state of Ember Data, which may actually just be the future Ember Data at some point as well.

CHARLES: It sounds like there is a pathway forward if that's the way that you want to go and the road that you want to walk so we'll look for that in the show notes. But my question then is, you're here on the podcast, what do you do?

TORAN: I do want to have one disclaimer here, just so that I'm not a complete poser but I am. If you guys don't know this, I'm not trying to hide this from the community but I don't work on ember-redux at work. I don't have a side gate, making money with it. I don't use it ever. I literally just build examples to try stuff out. There’s both a blessing and a curse of that. The curse is that you're asking, "Hey, Toran, you're the author. How does this work, man?" I can give you my run at it which I will but there is the other side which is very clear is that I have not built and shipped Facebook -- the current company I'm with -- with X million people hitting every month. We’re not using it. This isn't exactly 'Toran-stamp of approval' here but I do mess around with -- this week in particular -- Rx which I like.

I think Rx is just something that it changes the way you think about the way programming, especially async programming works. I definitely cannot comment much on Rx other than I like Alex's challenge to the community on your podcasting. Go use Rx, even if you use ember-concurrency or don't use ember-concurrency, how to break your brain. It will be for the better. Actually, Jay did a mini code review with me because my first pass at Rx was just using the fetch-promise because I was like, "I want Rx for side effect modeling but I wanted to still work with Ember acceptance testing," because I still feel like Ember is leading in that way, as you guys talk about in podcast recently.

What was really cool is actually there's a shim that obviously Rx has its own little Ajax thing but it is not actually Promise-based. The advantage of this that Jay called out is in the Promise-based, where I'm using ember-fetch, let's say and I'm just wrapping it with Rx, those Promises are still not really cancel-able so what Jay was warning me about is like, "If you're going to use this quick and dirty, great. but in a real app, these will still queue up in Chrome or IE and block the amount of network requests you can actually make," so don't use Promises, even though they're very familiar. Use this operator, I think it is or a helper inside Rx which is the Ajax non-Promise-based operator.

Long story short though, there's a good amount of work involved that grass is greener. In Ember Data, if you've ever used 'belongs-to' or 'has-many', you have done the most magical thing right there. In all the right ways, it is amazing because once you're in Redux and you're like, "I have this very nested object wrap," but Redux isn't meant to operate on this nested object wrap. It's meant to operate on this single tree structure, at these many top level entities as I can. As a project that's pretty popular in React called normalizer, you will likely use this project eventually. Maybe, not your first 'Hello, world', but you'll use this to actually break apart or truly de-normalized the structure.

What that does a lot of times is if you have a blog with comments nested all inside of it from your JSON API call or your GraphQL call, that's fine coming from the network. But since you're going to have different components listening for just the comments, maybe or different components that just listen and re-render when the blog name changes and they don't care about the comments, you want to actually de-structure that so you have a separate blog top level item and you have a separate comments top level item. They're still related so the blog can get through its comments and vice versa as belongs-to and has-many works in Ember Data but you've got to do that work now.

There is, of course magical projects like redux-orm that I just can't speak to how well they work or don't work but they try and solve the more Ember Data, look at the problem which has define this and there's the RM take care of the magic for you. I actually don't mind normalizer. It's just something people should be aware of because it's more work. You've got to break that apart yourself, just as much as writing your own network requests. You're, hopefully not going to duplicate Ajax all over the place but you will have to do the work that you otherwise do not do in Ember Data for sure.

CHARLES: It's very interesting. If you look at the Ember Data internals, it sounds like the Ember Data store is actually structured very similarly to the way you had structure a Redux store using something like normalizer where you have these top level collections and then some mechanism to both declare and then compute the relationships between these collections of top level objects.

But I want to go back to your other point too. I just wanted to say this. Toran, you know, don't sell yourself short because you give an incredible amount of time, an incredible amount of support to the community. You're very active in the Ember Redux channel. When problems come up, you think about them, you fix them. Even if you're not actually watering the trees, you're planting the seeds. I think that's actually great. I think that is a very valuable and necessary role in any community is to have people who are essentially the Johnny Appleseed of a particular technology. I think you go around and you throw these seeds around and see where they take root, even if you're not there. You're on to the next shady lane to plant seeds, rather than stay and enjoy the shade and the fruit of the apple trees.

TORAN: Yeah. I appreciate your kind words there because a couple of years ago, I got into open source because it provides good personal branding. It's like, "This project, it's Toran's. We should hire Toran." It just makes you look more from that perspective. It also gives you almost a way to skip out on tough interviews at times if people are like, "This guy have a decent program. Let's take a look at his PR. He communicates with other humans online." It gets rid of some of that.

But there is a dark side. We don't talk about it because there is an upside to it, especially for consulting but the dark side can be time commitment: how much bandwidth do you have outside of your family life, your hobby, if you have one and any other open source or work-related stuff that you already have to do. For me, this is really an exercise in thought leader-y stuff. I saw the benefits of this. It made my Ember better. Even if I wasn't using Redux, it just made the Ember code I wrote at work better. It inspired me to look at different things like ember-concurrency and Rx, things that are just way out of my comfort zone two years ago.

I think those are all the benefits that come with it but the easiest part is got to be some value from it. The juice is it worth the squeeze. I think the community we've built and the people using it and the problems we're solving are all definitely worth the squeeze.

CHARLES: It definitely is and you can tell from the vibrancy of that community that a lot of people are experiencing that value from it. To your point, I think something that is often lost on people is that you can actually use a project without actually using it. I think that there might be many people, for example in the Ember community that have never use React but are actually in fact using it because of the wonderful patterns that have come out and it's brought to the fore.

I had thought about immutability, certainly on the server side but I had thought about it really deeply on the client side until a library like React came along and people started talking about it. I would say before we actually started using React the library, we were using it in thought. You touched on that when you were saying, "It's changed the way I think, it's changed the way I code." Even it's changed the way that I do things at work, in fact you're using it in spirit, if not the actual structure but I almost feel like that's more important. It's longer-lasting and has a greater impact on you, 10 years down the road or even five years down the road when neither of the technologies that we're actually talking about today are even going to be in wide use.

TORAN: Yeah, that's true. In fact the one thing I would call out that people check out, I think Alex mentioned this or at least you guys have to talked about it in passing but definitely, sometime this weekend, watch the Simple Made Easy talk by Rich Hickey. It will definitely make you think differently, regardless of the simple side or the easy side that you follow on, projects of course make tradeoffs both sides of that but it is a great talk. Especially, if someone who's been programming six months or a year or two years, they're going to get huge benefit from it, just as much as someone older like myself who has got 10 plus years in the biz.

CHARLES: Yeah, I know. That is a fantastic talk. We need to link to it at every single show.

TORAN: Exactly.

CHARLES: Well, I think that is a fantastic note to end on so we will wrap it up. That's it from Frontside for this week. We’re going to have you back, obviously Toran there's so much that we could cover. Six months down the road, we'll do part three but for now, that's it. Thank you, Wil. Thank you, Toran for podcasting with us this morning.

TORAN: Thanks for having me on guys. I really appreciate it.

CHARLES: Then everybody else, take it easy and we'll see you all next week.

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069: Redux Part II with Toran Billups