7 ms·

Om Next – David Nolen [video]

259 points by ivank 11y ago

drcode 11y ago
So, in principle I like everything with David's new approach... the main question I have is "How well do 'recursive queries' work when the data relationships between my components is really complex?" I think I will only be able to answer that question by trying this approach myself and seeing how it performs for my needs. (Another question is: "How am I going to use this when my server's database is a blockchain and not a conventional database [1] like datomic?" but I know that's a niche question I'll have to figure out for myself.) [1] Just kidding (mostly)
- spion 11y ago
  Thats indeed something that doesn't seem to be discussed much, even if you look at graphql's presentation - https://www.youtube.com/watch?v=WQLzZf34FJ8 https://www.youtube.com/watch?v=WQLzZf34FJ8 there seems to be a lot of redundancy when "my friends including their events" is fetched. I imagine that a scheme based on an UUID and deduplication would work - when constructing the response an object repository is kept and if an object with the same uuid appears twice its replaced with a reference to them. Going against the "don't extend JSON" best practice, that would be: { "friends": [{ "name": "Name", "events": [#uuid1, #uuid2] }, { "name": "Another name", "events": [#uuid1, #uuid2] }], } #{ "uuid1": {"name": "MyEvent", "description": "..."}, "uuid2": {"name": "OtherEvent", "description": "..."}, } And it can support cyclic references too, as a bonus. Ignoring best practices is so... liberating. Ultimately this is just compression though. Its possible that gzip will be quite sufficient for most cases.
  - emidln 11y ago
    Transit [1] can do this for you. [1] https://github.com/cognitect/transit-format https://github.com/cognitect/transit-format
spion 11y ago
Quite amazing. This talk is not just about Om Next - its also about ClojureScript.next. Featuring: 1. AMD, CommonJS, ES6 module support 2. CLJS in CLJS (yup, that works - including the standalone nodejs based REPL) Thise in combination are especially huge. With core.typed being an option as well (once your system starts growing and the design solidifies) looks like the clojure ecosystem is really positioned to be one of the technically strongest available for web development. And of course, replacing that awkward REST mess seems painfully obvious now (except for duplicated data which seems like something that might yet need solving). Hindsight is 20/20
- lewisl9029 11y ago
  Does 1) mean we can make use of advanced optimizations (like dead code elimination) on libraries written in one of these formats without any additional configuration? If so, that would resolve what I consider to be one of the biggest barriers for CLJS/JS interop.
  - arohner 11y ago
    I'm pretty sure the answer is yes. I watched the video a few hours ago, but I think I remember him saying that. Of course, just like the current state of affairs, your library has to not thwart advanced optimizations (using eval, accessing properties by strings, etc).
  - jacobolus 11y ago
    Yes, that’s what swannodette said in the talk. Skip to 33 minutes, or see https://github.com/clojure/clojurescript/wiki/Google-Summer-of-Code-2015 https://github.com/clojure/clojurescript/wiki/Google-Summer-... and the blog posts at https://mneise.github.io https://mneise.github.io
- deleted 11y ago
  [deleted]
- dominotw 11y ago
  I felt like it was all over the place. I am not sure if I really care about all the people who are using graphql like syntax for data retrieval, I am not interested datamoic, falcor ect.
akilism 11y ago
Yeah, that was a great talk. I really want to try out Om Next. I've been building a bunch of stuff in Om lately and the Falcor/Relay/GraphQL/Om Next stuff is really going to be great to have at my disposal. The clojurescript compiling clojurescript stuff looks great too.
bsaul 11y ago
Why does the idea of having frontend guys directly query the db without any kind of interface scares me ? Seems like going the nosql to sql route once again( nosql is great until you realize query language and schema constraints are actually a good thing). Having some kind of pipe structure and interface between your db and your GUI that can be used as a contract,or as an intermediate level to do data rearranging, and can be documented, without having to know all the db schema internals really seems like a sound approach. Now of course some people tackling very special problems may reach the limits of such an approach, yet i hope it won't become mainstream too soon.
- spion 11y ago
  This presentation doesn't go into detail of how thats going to work between Om and Clojure, but if its going to be similar to GraphQL, then there is no problem. Every field request in GraphQL [1] maps really well to a method invocation on an object (GraphQL even supports arguments). Its not necessary that those objects in turn map directly to actual database entities... and you can of course do many things with methods, like authentication / authorization, or perhaps even (with async servers) delaying get() requests in order to aggregate them into a single IN query [1]: https://www.youtube.com/watch?v=WQLzZf34FJ8&feature=youtu.be&t=5m59s https://www.youtube.com/watch?v=WQLzZf34FJ8&feature=youtu.be...
  - bsaul 11y ago
    Thanks for the link. Very interesting talk. At then end though, you understand why they had to build such a system : dozens of apps, with weekly releases, and mutliple version support. Now of course, building an API supporting each of those apps needs is almost equivalent to supporting any kind of query. You might as well create a generic implemention, like GraphQL, which they did. But for the 99.99% of us, i don't think bypassing the API design phase is a really good idea.
    - spion 11y ago
      I don't think it qualifies as bypassing the API design phase. You still need to design the classes that map to GraphQL object, the methods they support, the authentication / authorization that those methods require and so on. All in all its pretty much the same thing as with a classic API. The only difference is you can send multiple (as well as nested) calls in one go, and decide which fields you want to include With this scheme you can even include/exclude fields based on user authorization! For example: class UserService { email() { if (this.context.user.id == this._id) return this._email else throw new CodedError(403, "Cannot request another users email") } } What is necessary now I think is an example open source app implemented with it to demonstrate how the stuff we do with regular APIs would work in GraphQL...
elwell 11y ago
> 41:15 Pretty sure Apple won't approve of being able to update iOS apps outside of their regular release cycle. If they don't care, I should be doing that now with my HTML5 app.
- reilly3000 11y ago
  I believe trigger.io has done this for a couple of years now
- wging 11y ago
  You can definitely do that now.
- elwell 11y ago
  Actually it may be fine, if it falls under this exception: 3.3.2 An Application may not download or install executable code. Interpreted code may only be used in an Application if all scripts, code and interpreters are packaged in the Application and not downloaded. The only exception to the foregoing is scripts and code downloaded and run by Apple's built-in WebKit framework, provided that such scripts and code do not change the primary purpose of the Application by providing features or functionality that are inconsistent with the intended and advertised purpose of the Application as submitted to the App Store.
agumonkey 11y ago
I guess the Gregor Kiczales slides are here: http://www.cs.ubc.ca/~gregor/papers/kiczales-oopsla-07-for-viewing.pdf http://www.cs.ubc.ca/~gregor/papers/kiczales-oopsla-07-for-v... (page 16)
winstonewert 11y ago
He mentions getting rid of cursors, but I'm not clear how he would replace the modification side of cursors. i.e. I can see how a system like he describes supports nicely querying data, how do it help a component that needs to trigger modifying data?
- 2bit 11y ago
  Exactly my question, this is a big missing piece and something that cursors solve nicely.
- Spendar89 11y ago
  I imagine you would trigger something like a datomic transaction, which returns a new version of the database.
- hojberg 11y ago
  A group of us talked to him after the talk, and if I understood it correctly, you'd still use the om transact function to trigger modifications.
Spendar89 11y ago
Swannodette never disappoints. If you're interested in this approach, you should check out re-frame: https://github.com/Day8/re-frame https://github.com/Day8/re-frame. The README is a great resource, regardless of whether or not you intend to use the framework.
- ds300 11y ago
  That README changed my life.
- Spendar89 11y ago
  And for anyone who'd like to jump right in: https://github.com/Day8/re-frame-template https://github.com/Day8/re-frame-template Includes Figwheel, and (optionally) Secretary.
andrewchambers 11y ago
Clojurescript in Clojurescript is demoed in the last 5-6 minutes of the video. I think this is an awesome way to ship a repl with applications.
avodonosov 11y ago
I am skeptical about "component knows what data it needs". For example, I have a component with two combo boxes: in the first combo box I select a country and the second combo box is filled with cities of that country. Now I need a similar thing: in one combo box I choose car brand, and the second combo box is filled with models of that brand. Can I reuse my existing component? If the component knows what data it displays, it can not be used to display different data.
- Skinney 11y ago
  If you need a generic component, then make a generic component. No one is forcing you to specify dependencies in all of your components.
  - avodonosov 11y ago
    OK :)
- jeremiep 11y ago
  David talked about the IQueryParams protocol in the presentation, it basically lets you parametrize the component's data.
zubairq 11y ago
I personally built my entire framework on top of Om, so always good to hear what David has to say: https://github.com/zubairq/coils https://github.com/zubairq/coils
andy_ppp 11y ago
I was thinking about this the other day and the web just magically solved all my thoughts and wrapped it up into a perfect video. Really excited about building my project in this (and learning clojure and Om Next).
pwr 11y ago
Has anyone an idea how pagination would work/look like with the presented query syntax?
drudru11 11y ago
Is there a description of how react avoids event listeners? How does it observe changes in a model? I've never heard that aspect associated with react before.
- mateuszf 11y ago
  It doesn't avoid them. You listen to events, and then you change your model. Based on new model view is rendered using the code you provide (one way rendering - model to code). Then React compares the two instances of rendered view (before the event and after) and renders the changes if there are any.

259 points by ivank 11y ago

So, in principle I like everything with David's new approach... the main question I have is "How well do 'recursive queries' work when the data relationships between my components is really complex?" I think I will only be able to answer that question by trying this approach myself and seeing how it performs for my needs. (Another question is: "How am I going to use this when my server's database is a blockchain and not a conventional database [1] like datomic?" but I know that's a niche question I'll have to figure out for myself.) [1] Just kidding (mostly)

spion 11y ago
Thats indeed something that doesn't seem to be discussed much, even if you look at graphql's presentation - https://www.youtube.com/watch?v=WQLzZf34FJ8 https://www.youtube.com/watch?v=WQLzZf34FJ8 there seems to be a lot of redundancy when "my friends including their events" is fetched. I imagine that a scheme based on an UUID and deduplication would work - when constructing the response an object repository is kept and if an object with the same uuid appears twice its replaced with a reference to them. Going against the "don't extend JSON" best practice, that would be: { "friends": [{ "name": "Name", "events": [#uuid1, #uuid2] }, { "name": "Another name", "events": [#uuid1, #uuid2] }], } #{ "uuid1": {"name": "MyEvent", "description": "..."}, "uuid2": {"name": "OtherEvent", "description": "..."}, } And it can support cyclic references too, as a bonus. Ignoring best practices is so... liberating. Ultimately this is just compression though. Its possible that gzip will be quite sufficient for most cases.
- emidln 11y ago
  Transit [1] can do this for you. [1] https://github.com/cognitect/transit-format https://github.com/cognitect/transit-format

spion 11y ago

Quite amazing. This talk is not just about Om Next - its also about ClojureScript.next. Featuring: 1. AMD, CommonJS, ES6 module support 2. CLJS in CLJS (yup, that works - including the standalone nodejs based REPL) Thise in combination are especially huge. With core.typed being an option as well (once your system starts growing and the design solidifies) looks like the clojure ecosystem is really positioned to be one of the technically strongest available for web development. And of course, replacing that awkward REST mess seems painfully obvious now (except for duplicated data which seems like something that might yet need solving). Hindsight is 20/20

lewisl9029 11y ago
Does 1) mean we can make use of advanced optimizations (like dead code elimination) on libraries written in one of these formats without any additional configuration? If so, that would resolve what I consider to be one of the biggest barriers for CLJS/JS interop.
- arohner 11y ago
  I'm pretty sure the answer is yes. I watched the video a few hours ago, but I think I remember him saying that. Of course, just like the current state of affairs, your library has to not thwart advanced optimizations (using eval, accessing properties by strings, etc).
- jacobolus 11y ago
  Yes, that’s what swannodette said in the talk. Skip to 33 minutes, or see https://github.com/clojure/clojurescript/wiki/Google-Summer-of-Code-2015 https://github.com/clojure/clojurescript/wiki/Google-Summer-... and the blog posts at https://mneise.github.io https://mneise.github.io
deleted 11y ago
[deleted]
dominotw 11y ago
I felt like it was all over the place. I am not sure if I really care about all the people who are using graphql like syntax for data retrieval, I am not interested datamoic, falcor ect.

akilism 11y ago

Yeah, that was a great talk. I really want to try out Om Next. I've been building a bunch of stuff in Om lately and the Falcor/Relay/GraphQL/Om Next stuff is really going to be great to have at my disposal. The clojurescript compiling clojurescript stuff looks great too.

bsaul 11y ago

Why does the idea of having frontend guys directly query the db without any kind of interface scares me ? Seems like going the nosql to sql route once again( nosql is great until you realize query language and schema constraints are actually a good thing). Having some kind of pipe structure and interface between your db and your GUI that can be used as a contract,or as an intermediate level to do data rearranging, and can be documented, without having to know all the db schema internals really seems like a sound approach. Now of course some people tackling very special problems may reach the limits of such an approach, yet i hope it won't become mainstream too soon.

spion 11y ago
This presentation doesn't go into detail of how thats going to work between Om and Clojure, but if its going to be similar to GraphQL, then there is no problem. Every field request in GraphQL [1] maps really well to a method invocation on an object (GraphQL even supports arguments). Its not necessary that those objects in turn map directly to actual database entities... and you can of course do many things with methods, like authentication / authorization, or perhaps even (with async servers) delaying get() requests in order to aggregate them into a single IN query [1]: https://www.youtube.com/watch?v=WQLzZf34FJ8&feature=youtu.be&t=5m59s https://www.youtube.com/watch?v=WQLzZf34FJ8&feature=youtu.be...
- bsaul 11y ago
  Thanks for the link. Very interesting talk. At then end though, you understand why they had to build such a system : dozens of apps, with weekly releases, and mutliple version support. Now of course, building an API supporting each of those apps needs is almost equivalent to supporting any kind of query. You might as well create a generic implemention, like GraphQL, which they did. But for the 99.99% of us, i don't think bypassing the API design phase is a really good idea.
  - spion 11y ago
    I don't think it qualifies as bypassing the API design phase. You still need to design the classes that map to GraphQL object, the methods they support, the authentication / authorization that those methods require and so on. All in all its pretty much the same thing as with a classic API. The only difference is you can send multiple (as well as nested) calls in one go, and decide which fields you want to include With this scheme you can even include/exclude fields based on user authorization! For example: class UserService { email() { if (this.context.user.id == this._id) return this._email else throw new CodedError(403, "Cannot request another users email") } } What is necessary now I think is an example open source app implemented with it to demonstrate how the stuff we do with regular APIs would work in GraphQL...

elwell 11y ago

> 41:15 Pretty sure Apple won't approve of being able to update iOS apps outside of their regular release cycle. If they don't care, I should be doing that now with my HTML5 app.

reilly3000 11y ago
I believe trigger.io has done this for a couple of years now
wging 11y ago
You can definitely do that now.
elwell 11y ago
Actually it may be fine, if it falls under this exception: 3.3.2 An Application may not download or install executable code. Interpreted code may only be used in an Application if all scripts, code and interpreters are packaged in the Application and not downloaded. The only exception to the foregoing is scripts and code downloaded and run by Apple's built-in WebKit framework, provided that such scripts and code do not change the primary purpose of the Application by providing features or functionality that are inconsistent with the intended and advertised purpose of the Application as submitted to the App Store.

agumonkey 11y ago

I guess the Gregor Kiczales slides are here: http://www.cs.ubc.ca/~gregor/papers/kiczales-oopsla-07-for-viewing.pdf http://www.cs.ubc.ca/~gregor/papers/kiczales-oopsla-07-for-v... (page 16)

winstonewert 11y ago

He mentions getting rid of cursors, but I'm not clear how he would replace the modification side of cursors. i.e. I can see how a system like he describes supports nicely querying data, how do it help a component that needs to trigger modifying data?

2bit 11y ago
Exactly my question, this is a big missing piece and something that cursors solve nicely.
Spendar89 11y ago
I imagine you would trigger something like a datomic transaction, which returns a new version of the database.
hojberg 11y ago
A group of us talked to him after the talk, and if I understood it correctly, you'd still use the om transact function to trigger modifications.

Spendar89 11y ago

Swannodette never disappoints. If you're interested in this approach, you should check out re-frame: https://github.com/Day8/re-frame https://github.com/Day8/re-frame. The README is a great resource, regardless of whether or not you intend to use the framework.

ds300 11y ago
That README changed my life.
Spendar89 11y ago
And for anyone who'd like to jump right in: https://github.com/Day8/re-frame-template https://github.com/Day8/re-frame-template Includes Figwheel, and (optionally) Secretary.

andrewchambers 11y ago

Clojurescript in Clojurescript is demoed in the last 5-6 minutes of the video. I think this is an awesome way to ship a repl with applications.

avodonosov 11y ago

I am skeptical about "component knows what data it needs". For example, I have a component with two combo boxes: in the first combo box I select a country and the second combo box is filled with cities of that country. Now I need a similar thing: in one combo box I choose car brand, and the second combo box is filled with models of that brand. Can I reuse my existing component? If the component knows what data it displays, it can not be used to display different data.

Skinney 11y ago
If you need a generic component, then make a generic component. No one is forcing you to specify dependencies in all of your components.
- avodonosov 11y ago
  OK :)
jeremiep 11y ago
David talked about the IQueryParams protocol in the presentation, it basically lets you parametrize the component's data.

zubairq 11y ago

I personally built my entire framework on top of Om, so always good to hear what David has to say: https://github.com/zubairq/coils https://github.com/zubairq/coils

andy_ppp 11y ago

I was thinking about this the other day and the web just magically solved all my thoughts and wrapped it up into a perfect video. Really excited about building my project in this (and learning clojure and Om Next).

pwr 11y ago

Has anyone an idea how pagination would work/look like with the presented query syntax?

drudru11 11y ago

Is there a description of how react avoids event listeners? How does it observe changes in a model? I've never heard that aspect associated with react before.

mateuszf 11y ago
It doesn't avoid them. You listen to events, and then you change your model. Based on new model view is rendered using the code you provide (one way rendering - model to code). Then React compares the two instances of rendered view (before the event and after) and renders the changes if there are any.