If you're using Node.js, you're doing life wrong
codeslinger.posterous.com
codeslinger.posterous.com
This remark is off the mark. Dependency injection, as in injection by parameters and injection by constructors are so obvious people do it sub-consciously. A fluff word isn't needed for it. As far as IoC containers are concerned, I don't see Ruby/Python communities using it, mainly because half of it is fighting static typing.
And people are learning proper modularization now? Seriously? Python/Ruby has proper namespaces(ruby doesn't have it), modules, classes et al. Like any other languages, Python/Ruby has it's share of programmers who write spaghetti code, and programmers who don't.
Again, if he writes AbstractConnectionDepenencyInjectioManagerAbstractFactory and calls it proper modularization, I am happy Python/Ruby isn't picking it up.
I posted some commentary on the same topic last time Nick Kallen's infamous "I love everything you hate about Java" blog got posted : http://news.ycombinator.com/item?id=3287777 .
What it boils down to is that Java likes invoking the names of design patterns with all sorts of pomp and ceremony (look, ma, it's an AbstractFactoryFactory!) while many more modern languages make similar design patterns natural.
Whether or not to like the ritual is up to the programmer, but I entirely agree that claiming that Ruby and Python are "just starting" or "don't" support patterns like dependency injection is absolutely baseless.
> As far as IoC containers are concerned, I don't see
> Ruby/Python communities using it, mainly because half of
> it is fighting static typing.
http://weblog.jamisbuck.org/2008/11/9/legos-play-doh-and-pro...
He's calling node style callbacks spaghetti code. Which it is, and it's a known problem, and there are several half-baked solutions for it.
> Not to mention the fact that its balls-ass slower than some straight un-optimized Scala.
I don't see the point of comparison here. Slower/faster is meaningless without the context. Apples to Oranges. And, Scala has it's own issues. Yeah, the JVM's performance is there, but bringing your team onto a Scala codebase is not easy either.
> It provides the least amount of aid and comfort to the programmer and its nigh-on-impossible to follow the code 6 months later.
Anyone who has developed more than a Hello World in Node will know that the problem of callback sphaghetti can be circumvented using events, promises and async libraries. Yes, until the language itself offers an async construct, this will be an issue, but frankly there are ways to get around it.
> JavaScript has very little support for any of those nice things: it doesn't even have namespaces, for chrissakes.
Client side JS has no module system. But Node.js has. At this point, I really wonder if the OP has actually worked at all with Node.
> It seems to me that people who are really crazy about Node.js are people who only knew JavaScript to begin with and to whom none of the above would ever even occur.
Another baseless claim. I urge you to go see the GitHub profiles of Node core committers. Seriously.
Check out requirejs: http://requirejs.org/
I've used it to handle both server-side (node) and client-side module systems, and it's been great.
edit: phone keyboard typos
I'm using node for a small tool to analyze network traffic. The author of this drivel can cope. :P
We're all aware of the Internet Hype Machine. We've all been duped by it before. Heck, my big project today consists of frantic backpedaling from an overly hasty decision, prompted by the IHM, to use SQLite in a project that had no business being based on SQLite. We should all be open to hearing criticism about choices to use X or Y technology.
-But- if you start by saying, "You're so stupid," then the person you're talking to will start by thinking, "You're such a jerk." And nobody really pays much attention to the opinions of people they think are jerks.
Socrates was smart. He was also executed for being irritating.
You know, much alike someone insulting Mongo, Rails or Node in certain communities... (or Java, CL etc in others).
Again, much like Mongo, Rails, and Node. :)
It's not limited in scope to someone else's work. I have done a decent review of a number historical computer science papers, I can confidently point to a number of things that have been pointlessly reinvented over the years at least once, if not 2-3 times.
It's like, why are people using these really bad technologies (node for instance)? There are are solid and advanced technologies that have done all these things, been tested, used, and developed over a long period of time, without the limitations of this newness and lack of features/testing/experience.
As a stupid example, a tracing simulator describing variable usage and coverage were commercially available for Fortran in the late 60s. I haven't heard of similar systems for C or C++ in my casual reading on C and C++. Perl has spent years working towards something that is starting to look a good deal like Lisp in Perl 6.
For node.js and golang and other asynchronous & message-based languages/platforms, see occam.
Why can't we look into the 70s and build new technologies instead of reinventing the same ones over and over again? That's why I get a bit miffed about new stuff that is the same as the old stuff, except Now For Modern Computers/The Web/Mobile/blah.
Good example of your point, this is one of the things frustrating me in life.
Most of the scripting languages have long been working on becoming larger subsets of Lisp. They still mostly haven't gotten close in e.g. efficient compilation.
But sure, it would be cool if the Perl 6 e.g. really implemented a good macro system without sexpr functionality. Something to look forward to.
I really don't understand how the Lisp people failed taking over the world. (Sigh, I should have helped instead of being sidetracked after univ. :-( Maybe I should start looking into Perl 6 development.)
It starts off strong talking about a high bug count, but never gets into specifics there.
As far as scaling across cores goes, it's disingenuous to suggest that node can't do this, there are a number of options here. Message passing, for instance, does indeed work.
As far as nested callbacks sucking, I totally agree. But a walk through why would add a lot more substance here as well.
Keeping it to node.js bashing, this guy takes the discussion to a slightly lower level: http://youtube.com/watch?v=1e1zzna-dNw
He tries to discredit node by taking apart the copy on the front page of nodejs.org.
It's all conjecture and ad hominem.
I also won't be surprised if their rewritten scala HTML parser also dominates the bug counts.
Javascript doesn't have this (by itself) but node has a very nice require() system that is really excellent for long-term maintainability. When you bump a dependency in a node project that change will only affect the code near it because of how node_modules are resolved to the most local copy. You can bump dependencies without worrying how this will affect other packages.
Plus, require() just returns an object. It doesn't puke a bunch of objects into the current scope. This is massively useful for readability. I've sunk a lot of time on other systems tracking down unqualified exports to figure out which package's documentation to consult.
I've got nothing against scala and am sure it's a useful language but I wonder if the author has even used node.
* It's "not as good" as languages/environments like Erlang.
* But it's good enough, and significantly simpler, as an approach to tackle a certain class of problems. This, combined with widespread knowledge of Javascript, will probably make it fairly widely used.
The fact of the matter is that Javascript is currently (and for the forseeable future) client side language that runs without a plugin. If you want your entire stack to run on Javascript, then server side programming is the only way.
Projects like CoffeeScript are the earmarks of disruptive technology - getting something that doesn't fit most peoples needs to grow up quickly, fit everyone's needs, and destroy its competition before the competition even realized it was there.
At a very basic level, Node.js is a callback-based API that's based around some(probably select) notifier loop. That's not particularly new.
Of course, scaling it past that will be a problem with Node being single threaded and so on - but I believe that these are problems that Node.js will eventually address.
However, Node is written from head to toe to take advantage of that style of coding, whereas Tcl never had the assumption that everything had to be async, so many calls block. Same thing with Python and Ruby, except that they're relative latecomers to the embedded "select loop" game (sure, modern systems have moved on from select, but it still conveys the idea).
Erlang has been around for a while, and does async beautifully, but for every person who knows Erlang there are 10,000 who know Javascript.
* If I read correctly, OP is using Chrome/V8 directly. I don't see if the bug list is on V8 itself or his bindings?
* "Callback Spaghetti". To each his/her own. I happened to read callbacks easier than other solutions. And this is coming from Python programmer, not JS programmer.
* The last 2 points are also information-less rants. What happened to HN?
It's a community built around an implementation of a language which they do not control. Who is Guido or Matz in node.js? Ryan Dahl I suppose; does he take requests or hold discussions concerning the future evolution of the language? Does he issue any rationale documents concerning his language design philosophy? Could he add multithreading to V8 and if so, why hasn't this happened?
It's a community built around someone else's tool, and Google develops it for entirely different reasons. Case in point, someone posted IcedCoffee, which adds an "await" keyword to CoffeeScript -- you have to implement a compiled language on top of Javascript to have the language features you need!
Finally, to preempt questions about my being concerned about other people's language choices -- other people are choosing, inexpertly in my opinion, the technologies with with I will contend in the future. Future employers may value and demand experience in node, and future employees may have to be disabused of bad habits accumulated during the learning of it.
But if that's so, then simply view this as an explanation for why I don't use server-side Javascript. And Node is still a tool built around a language implementation which is going in a different direction from where a server side environment/general-purpose language needs to go.
• Node.js is a framework built by people other than the language's core maintainers (which is true of most frameworks)
• If you want to add fundamental language features, you can't just force it into the core implementation, but will have to implement your own offshoot (which is true of most languages, including, for example, Clojure)
If you're really concerned about other people's language choices, you're going to need concrete reasons, not just generalities, vague insinuations and your own personal preferences.
(Edited a bit to clarify and because the original phrasing sounded more combative than I intended.)
I'm not sure what I can do to clarify the point anymore: the V8 engine is created and maintained for the purposes of speeding up a web browser's processing of Javascript within the context of an HTML document. The goals of the team implementing the runtime are not to create a general purpose language, they are to create an engine which excels at one specific use case, and granted this use case is broadening over time.
But to address your point: yes, the developers of Pyramid (to take an example) have not to my knowledge submitted code to e.g. optimize networking functionality in core Python so that it better suited their specific needs. On the other hand, the Python team has had an excellent track record in observing and adapting to trends within their community -- the introduction of WSGI is one such example.
The Python community has a PEP process for generating discussions about what the language needs. To my knowledge, there is no discussion within the V8 developer community about how to make the engine more suitable for server-side programming. And how would you begin the process of adding general programming features to the language itself? Join ECMA?
If you're really concerned about other people's language choices, you're going to need concrete reasons, not just generalities, vague insinuations and your own personal preferences.
Excellent editing. Much less combative.
EDIT: Actually I'd like to add a couple more things:
Node.js is a framework built by people other than the language's core maintainers (which is true of most frameworks)
That is not a point of contention. That is a simplistic reduction of my point which conveniently serves your argument.
If you want to add fundamental language features, you can't just force it into the core implementation, but will have to implement your own offshoot (which is true of most languages, including, for example, Clojure)
This entirely misses the question -- why use a language whose core feature set does not cover your use cases? Why use a language where you must extend the language to get fundamental features? Moreover, no you will not have to implement an offshoot to get core features. At the risk of repeating myself: when you have control over the direction of the language's evolution, you can petition and propose changes.
And I think it's kind of a basic misconception that V8 is made just with web browsers in mind. If you look on the V8 developer site, nowhere does it say anything close to that. Their stated objective is "fast execution of large JavaScript applications." They go out of their way to draw a distinction between the browser and the engine, explaining what is and isn't part of JavaScript (e.g. the DOM is just an interface that browsers choose to expose). Is Chrome the original client for V8? Sure. And shell scripts were the original use case for Python. It seems to me that "V8 is just a browser language" is the new "Python is just a scripting language."
And I wouldn't describe the language-level ability to write asynchronous code in a synchronous fashion a fundamental feature. It's really cool and allows a lot of expressiveness, but so would a lot of potential changes in, say, Ruby. If you don't want the language feature, there are really nice libraries that get you most of the way there. (And I don't really see how the existence of CoffeeScript or ICS is any more an indictment of V8 than the existence of Scala is of the JVM. Choice is a good thing. Lots of people prefer vanilla JavaScript.)
I don't go around saying, "Snickers is the worst candybar, therefor anyone who eats a Snickers is wasting their time."
I bet the author is not a pleasant person to work with.
I like node for system level scripting. I find bash annoying and non portable to windows. I really don't want to have to learn batch scripting for dos on windows. But I can use JavaScript with node to script in both environments.
On the server I think that node might be helpful for certain network level tasks. But I haven't used it for much. But honestly what type of person would I be if I don't even consider it? The OP seems to be making an emotional decision rather than a technical one. Interestingly he's using Scala. There are many similar posts about Scala being the wrong way to do life. I just can't agree with any of those views.
Finally I wonder what the value is for these rage posts. They just seem to further divide people. I do see the value in the posts about I've used node for X months, here's my thoughts or here's why I'm going back to X paradigm. But just a rant where faces should be punched seems out of place for HN.
Don't let the name fool you, it's not only for databases. I would say that it's probably more suitable for general purpose scripts than Node, though some of the APIs are a bit clumsy.
It's not open source, but it's free and cross platform and actually pretty good for a lot of general purpose scripting. Seems that it is developed by a single guy. I found out about it a few years ago and used it to get some things quickly done.
1) If you don't know technology X and use it due to hype, you deserve to get burned
Let that be a lesson for anybody.
2) There's no silver bullet
Choosing node.js over web-framework just because you want the front-end and the back-end to use the same code-base is to trade one feature for another: Ruby and Rails still have better tools than Node.js while you get JS all over the place (assuming you're good with JS).
3) Complaining about the language is a sign that you have no clue
I used to think that Java is better than some of the hype dynamic languages out there but I was wrong: Java is better for ME because I _KNOW_ Java Better. If I know Ruby more than I know Java then Ruby is better than Java FOR ME.
4) Don't program using another language's idioms
This is documented left and right already. If you use technology X, find best-practices for technology X. Don't just apply best-practices from technology Y.
http://dirtsimple.org/2004/12/python-is-not-java.html
Or some of the comments here about Dependency Injection (which is quite common in Java but not so in Python/Ruby).
In the past, I had one instructor that noticed that my QBasic code looked like Fortran. He asked me if I knew Fortran beforehand and I told him that I've taken Fortran before this class.
People see and notice.
Out of the box the callback model can be difficult to wrap your head around. But if you are serious about writing a vertically scalable IO-bound service, it is currently the only option. There are some add-ons to make the code less ugly, but you still have to have the mental model down.
It's a lot like multi-threaded programming, or functional programming. It's a matter being able to visualize the flow and pass context around. This takes time to change the way you think.
If you approach problems in Node like you'd approach a problem in a functional language the spaghetti of callbacks becomes much less of a burden.
For the async haters out there operating at scale. How many of you have farms of machines with idle CPU's, maxed out memory, and practically idle network interfaces? Yeah, I thought so.
This tech talk on node is pretty interesting
http://sna-projects.com/blog/2011/08/nodejs/
I watched it last weekend, and from what I understood/remember from the talk the reason the node people picked javascript was not because they liked javascript. It was because they wanted to do async programming, and they found other languages had too much synchronous baggage. In javascript, node.js could start from a clean slate and build a pure async culture and environment.
Until I see an actual example of how "Node.js crashed my business, cost us N dollars, and here's exactly how...", I will continue to look at such posts as developers complaining about having to learn to do things a new way — something that has been going on since there were developers.
TameJS is a step in the right direction by adding a C#-style await.
* Before native support: https://github.com/learnboost/cluster
* Now, native: http://nodejs.org/docs/latest/api/cluster.html
But it is a good trick. Node.js deserves credit for calling attention to an underappreciated design pattern that has a lot to offer in certain circumstances. (Personally I think the .NET team hit the nail more squarely on the head with TPL, a pony that can do that trick as well as many others. But .NET doesn't have the sex appeal it takes to be a spokesmodel so meh.)
Javascript isn't my favorite language, or the most performant one. But as a "Lisp with C syntax", on a semantic level it's much better suited to the higher-order programming techniques that the pattern requires than most other popular Web languages are. Ruby also has the right features, but it isn't exactly the poster child for high-performance computing either. Might as well flip a coin, because either way opinionated folks with blood pressure conditions will call you an idiot.
But the callback spaghetti problem can be largely solved by dropping in, for example, the IcedCoffeeScript fork:
http://maxtaco.github.com/coffee-script/
Or the previous JavaScript TAME functionality:
There are of course many other async helper solutions as well, and if you're doing serious Node development, it's kind of insane not to use one of these.
* It uses non-blocking evented IO so it can scale well.
* It is single threaded so it can't scale well.
Someone teach me: which of these statements is true?
Non-blocking evented IO is mostly attractive from a usability point of view: it's much easier to write programs that aren't multi-threaded. It can also use much less memory than a threaded model in certain situations.
Non-blocking, evented systems tend to be single-threaded. Single-threaded systems don't automatically scale across multiple cores. To scale, you spawn a separate process for each core (for example, this is the suggested practice for node). You must then find some way for the different processes to communicate with each other, which is usually through a database (or some crazy pub-sub thing).
Node can scale just fine if you design your program to do so. It just scales in a different way.
Async IO is an absolute win from the scalability perspective because it allows you to service a great many clients with many fewer threads. OS thread context switches are relatively expensive. Ideally you would have exactly one OS thread per physical core and they would never need to block on exclusive access to any shared resources.
Now that we have a system where the user code inside the async handler doesn't need to manage exclusive access to anything, from the usability perspective it can has some of the simplicity of code that is fully single-threaded. But that's subtly different from saying ASIO makes it easy.
My guess is that many of the same programmers who aren't comfortable writing multithreaded code aren't going to find it completely intuitive to rethread their stack around an ASIO model.
Essentially the first one is most right. Non-blocking IO can get a lot of work done as it is never hindered by doing nothing while waiting around for slow IO. It never blocks so it can always do work.
However, if a non-blocking system has too much work to do it can still max out a CPU. At this point you, ideally, need as many worker threads as you have CPUs.
However, a threaded system that doesn't use non-blocking IO runs the risk of having many blocked threads eating up a CPU & memory instead. This is largely dependent on the light-weight-ed-ess of the threads.
Both these systems are effected by how much work the server has to do to create a response, thus even non-blocking IO can become swamped if it uses a slow language, too much memory or the wrong algorithm, plus all IO must not block or else the non-blocking networking ends up waiting around for blocking files.
There are other complications too like the number of file handles a process can issue that can also impede a server and the number of clients it can simultaneously serve.
If you're working on a project where I/O blocking is your primary performance issue, Node has a lot to offer in the form of a framework that helps and encourages you to structure your code in a way that works well for such tasks. Javascript's performance and its being single-threaded will have minimal impact, because those concerns are absolutely dwarfed by I/O costs in the situations Node's designed for.
On the other hand, if you're worried about how many threads you can run at once, then you're working on a task where CPU performance matters. That's not what Node is designed for. If you use Node anyway, you've decided to try hammering screws into place - and you should absolutely expect that it won't work out very well for you.
I just spun up a IM API we needed in an evening thanks to Node.js and community contributed packages. It's humming along great, I even wrote up a piece about it: http://news.ycombinator.com/item?id=3547664
Who cares about the language. Use JS if you want, or use Scala. At the end of the day is the maintainability of the product you're developing that matters.
I feel, for example, that NPM is much easier and simpler to use than something like Maven. If it makes my life easier, I'll stick with it.
WTF?!
Is there a need for webstackers to go play at the server side? YES! but node is not THE solution, it is just ONE solution. I venture to say, as javascript evolves more towards a coffeescript flavor, then a coffeescript flavor on the server is what is needed.
And I'll support something along these lines.
Just use it and see if it works out for you.
The only factor that drives technology success is the people, aka the community. There are a lot of people on board of nodejs. This just creates more gravity and pulls more people toward it. Together, the community will carry the momentum that drives its success. If v8 is not server technology like OP said, there are enough open source developers to make its on fork.
You're a pretty good Python developer. You know, and feel comfortable with, not just Python, but the entire ecosystem. Virtualenv, pip, the whole nine yards. And now you're working on a really nifty Django app, maybe a CRM or something, when you realize...
...damn. This app really needs a lot of functionality ripped out and shoved in the browser. I'm losing my marbles writing spaghetti jQuery code, but what I really need is some client side templates.
So you poke at it, and think about it, and you realize that the proper design of your app is really a bunch of client-side code using Backbone, and a server that just handles authentication and is otherwise a thin RESTful wrapper around your database.
Great! But at this point, most of the actual code you will be writing is Javascript. Your server could be written in, practically, anything. And there's some compelling reasons to leave it in Python. On the other hand, if you switch to node.js it means all your code is in the same language (which is nice). It also opens the door to being able to use the same code on both the client and the server - which is really good. Client-side templates are nice, but being able to render them on the server when you need to is practically a requirement. And Python's support for rendering Javascript templates is very limited. And if you're a Python coder, you'll probably want to be writing your client in CoffeeScript anyhow, which requires having node.js installed, so, at least for development, just have the whole damn stack in node.js. You can always hack together a little RESTful server in Python later if you decide that node.js isn't right for production.
Seems simple enough, right? And as you can probably guess, I just went through this process. And so now we have this blogpost, which is saying...well, it's not really clear what it's saying. That I should be using Scala, I guess. This is, frankly, so wrong it's embarrassing.
1) Even if the JVM was just so amazing and awesome, I'm not a JVM developer. The ecosystem is radically different. As a Python developer, I'm able to install, configure, and be productive with node.js very quickly. npm, nvm, coffeescript, and we're away. My IDE of choice (PyCharm) even supports CoffeeScript. There is very low impedence. Switching to Scala...where would I even begin?
2) I'm doing this because I need to write a client side app. That must be written in Javascript, or something that compiles to Javascript. Scala is neither. And while there are JVM language that do, there are some major concerns with their suitability, maturity, and tooling. Clojurescript looks great, but it's not something you pick because you think coffeescript is too new and little used!
3) The rant would be more compelling if the author came across as someone who actually knew anything about Python, Javascript, or node.js. Contrary to his assertions: Javascript does have namespaces. Python and Python developers have ALWAYS been convinced that modularity is good. And Python developers are still quite aware that dependency injection is a way to solve problems with the design of Java which aren't even relevant to their language of choice.
4) Also, if you don't grok callbacks, it doesn't mean you are a bad programmer. But it might be worth keeping in mind that there are plenty of programmers who do, and they're going to laugh at you when you reveal you don't. Not to mention that there are plenty of ways of programming in node.js WITHOUT callback spaghetti, and revealing that you have no clue about the framework your slagging is not going to improve your credibility.
5) To continue the theme, insulting a framework for not scaling well may work better if you don't reveal that you don't know how it scales in the same paragraph.
If you've already finished your project, I'm not going to try to convince you to move away from Node, but if you've got a lot to do still, you might consider sticking with Python. I'm not saying that Node isn't a workable solution on the server side, I just don't think it's proven that it is the way that Python and other, more mature platforms have. I don't give too much credence to inflammatory posts like the one being discussed, but when I see posts like: http://news.ycombinator.com/item?id=2519674 from a developer I respect, it gives me pause. That post is 18 months old now, so the situation could have changed.
There's something to be said for building things you know are rock solid and won't result in 2am notifications. That's my perspective, so I try to stay away from the bleeding edge. For stuff that's not critical, I'm more ok with taking a few risks. But someone's got to be the one that takes those risks in a mission-critical environment to figure out which of the new technologies will become proven and which will fail, so I disagree that these people are doing life wrong. If it wasn't for people like them, my way of doing life right wouldn't work.
The little layer of emotion and drama added here gets the point across much better, IMHO. Of course it doesn't do anything but preaching to the choir (hi there), and not convincing anyone not already in the choir, but it's a great read! (and so is this thread).
In other news, if you're voluntarily using a dynamically typed language and an editor without an integrated debugger, you're not fit for programming!
"But the kind of misunderstanding going on in this video clip seems to pervade the Node.js hype and gives me rageface."
This seems like a really over-the-top response to people that have a differing opinion. I can't take the rest of his post seriously after reading these parts. This certainly isn't the sort of thing you read in an informed opinion piece.
He seems to have some valid criticism, but I can't say it's anything I've heard before. If anything, the article itself is flamebait and at least partly intended to troll.
After browsing through the comments here on HN, I think he succeeded. But then, everyone likes a good flame war once in a while...