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What's the Secret Sauce in Ruby on Rails?
An anonymous reader writes "Ruby on Rails seems to be a lightning rod for controversy. At the heart of most of the controversy lies amazing productivity claims. Rails isn't a better hammer; it's a different kind of tool. This article explores the compromises and design decisions that went into making Rails so productive within its niche."
Fact is that Rails template (rhtml files, the views) are scripted directly using Ruby (there is no specific view/template language). This means that they can be abused, not that they should.
When used well, Rails views are actually quite clean due to the high readability of Ruby itself and the ability to rapidly create so-called Helpers (Ruby methods that you can call from your views, to build specific HTML structures from generic datum, since you come from JSP land think Taglibs, but much simpler to define & use)
Seems like DHH found Ruby simple enough to just use it as a templating language (and it works quite well), that's his choice, other frameworks in other languages picked a different one (Python's Django has a template-specific language for example, much simpler and less powerful than full blown Ruby but much less prone to abuse either)
"The way we can tell it's C# instead of Haskell is because it's nine lines instead of two." -- wadler
I've only used Rails a bit, but I've used Ruby a lot. It's by far the most flexible language I've ever used. It allows programmers to modify the most fundmental aspects of the language. Some argue this is a bad thing, and it may be. However, having the freedom to do that is very empowering. Don't get me wrong, other OO scripting languages are great too... Python for example. And, they share many concepts with Ruby. The things that make Ruby stand out (to me) are the ease of modification and syntax flexibility. IMO, Ruby is a wonderul toolkit that will allow one to build most anything, even more specialized tools like Rails.
As far as I've seen, there isn't that much actually new in RoR. But it's obvious that someone has had a great idea how a whole bunch of known stuff should fit together, in a way that encourages best practices (like a lot of testing, and code reuse). It has near perfect design.
The language Ruby wasn't new; Active Record wasn't new, nor was the idea, but it fits with Ruby really well. MVC was old, but the tiny bits of boilerplate needed makes it look like magic now and then. Everybody knows testing is essential, but I hadn't seen it integrated into a web framework so well before. The idea of "sensible defaults" can't have been new, but the switch from reams of XML (in Java web programming) to near invisible config is great. The object-oriented Javascript libraries it uses weren't new, nor are template languages, but the way in which they're added together is pretty seamless. Et cetera.
No wonder every web programming language community out there is rushing to put together it's own version of Rails... but the libraries don't always fit together as seamlessly. I think that Hansson's main achievements are recognizing that all the known best practices can be put together really well, and that Ruby and its libraries were a great fit for that.
I believe posters are recognized by their sig. So I made one.
I tried Rails for a bit. Found it nice. I found the language Ruby more interesting than the Rails framework. Rails code I looked at looked very much like JSP/ASP/PHP gone bad. All sorts of code in HTML land. Then their was the compilation oddities.
I still believe that Java and PHP are better though. They also perform a hell of a lot faster and scale much better. For example, a friend was creating a site with Rails and wanted to put in integrated search. Several people attempted creating something like Apache's Lucene in Ruby but found that the Ruby's poor performance made the search incredible slow (you could time out before it finished getting your search results).
What I would think would be really cool is a Lua plugin for Apache. That would be sweet.
(Django has been in use on high-volume production websites longer than Rails has existed, incidentally -- something which might be worthwhile when bringing it up in this kind of context).
After evaluating Rails and Django, my company ended up going with TurboGears for some of our toolage (our main product is a Java Servlet-based application, and that's not changing). The reasons:
The opposing reasons:
Anyhow -- Rails is nifty. Django is nifty. TurboGears is nifty. Quite likely all three of them have a place; I'd just like to urge people not to get so caught up in the hype over Rails that they forego evaluating other options.
thar RoR is using Ruby, a programming language that:
a. is fully object-oriented (not a hybrid like c++ or java). For example, you can have "hello".length() or 5.inspect() which means easier debugging and easy extensibility when you can ("can" != "should") add methods to any class at runtime.
b. supports mixins (flexibility of multiple inheritance without the complexity)
c. supports blocks and closures (if you've never used a language that supports blocks and closures, then you don't know what you're missing. I've coded professionally for more than a decade using assembly (intel & motorola chips), c, c++, cobol (ugh), delphi, java, python, etc. and when I discovered how to use blocks and closures in Ruby last year, I almost fainted because it makes coding so much more productive)
d. practical for both one-liners like perl and large/complex applications with a GUI interface
When I discovered Ruby last year and tried RoR for the first time this month (stayed away due to dislike of hype), it felt like I was previously chopping trees with a plastic spoon all this time instead of using a chainsaw--Ruby succeeds because it takes so many great features from other languages and combines them in a cohesive manner. RoR succeeds because it uses Ruby and provides a framework that encourages good coding (by providing MVC for example).
But there is a price for all of this. Speed. In order to provide so many productivity features, the performance will never reach that of c, c++, and many other languages. And I don't know when/if a compiler will ever be practical or available (like gcj for java producing huge binaries to print hello world).
Other drawbacks include poor release management (remember the ruby 1.8.3 fiasco) and poor support for wxWidgets (Ruby has better support for Fox toolkkit, but I use wxWidgets with C++ so this isn't ideal for me).
Anyway, I hope another new language comes along that'll blow away Ruby and another new web framework comes out that'll blow away RoR.
Blind loyalty to language/os/software/etc is for idiots who are afraid of change. Be aggressively disloyal to your products and force their developers to improve or fade away.
To enable some of the RAD Ruby will infer much information from simple syntax and naming schemes. So if you start a class naming it Person, Ruby will look at a table called People to try to figure out the different fields/properties for that class. That's why it comes with some knowledge about plurals built-in.
It's probably not that disturbing if you are used to it, and it is exactly what makes Ruby so fast for development. It's convention over configuration. In a different toolset, you might have to make a mapping from class to table using XML for instance.
It really is tiresome to see people constantly ask "what's the special sauce" when in many instances it is clearly "nothing".
Sometimes good people use good methods to build well conceived applications that work precisely as their audience expects they should. Because these well-formed applications do not fail randomly, scale well and are easily supported marketing and business types presume that there absolutely must be something patentable in the mix.
One of the reasons I loath the term "Web 2.0" is because people presume there is some new wave of innovation occuring in application development when every Slashdot reader know's this isn't true.
Technologies mature, standards mature and hopefully people mature. The result is better software, not an abundance of new and novel special sauces.
That's one of the biggest things going against Java for the casual developer market too. Most shared hosts don't support Java for this very reason. You can't have users bringing down the server every time they need to update their code. This is probably the biggest reason why PHP is still as popular as it is. It's where a lot of developers get their start. I would love to use Java for my web development uses, but I'm not about to spend the money necessary to have web hosting that supports Java. I've also heard that there's some shared hosting companies that support Java, but they restart the server every night in order to accomodate this.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
I interviewed the article's author, Bruce Tate, for the Ruby on Rails Podcast. He's a brilliant thinker and has taken bold steps to embrace Ruby inspite of his fame in the Java community.
Rails Podcast with Bruce Tate
[Everyone gasps.]
Hermes: No!
Fry: Ah, so the real gift Spargle gave you was confidence. The confidence to be your best.
Farnsworth: Yes, ordinary water.... Laced with nothing more than a few spoonfuls of LSD.
Shop as usual. And avoid panic buying.
1. It's easy to build hash tables in Ruby- At any level of a hierarchical structure like HTML you can have an arbitrary number of child elements or attributes, all identified by a type tag. This happens to map perfectly onto ruby's hash tables, so to create an HTML link you can say:
:id => 'add user', :class => 'shiny button', :action => 'add_user'
link_to
2. Lack of superfluous syntax It is very elegant how every programming idea in ruby seems to require only a single syntax concept at a single location to put it into practice- For instance, if you need a class member variable, you just create a name starting with "@" (like @firstname) without having to declare the variable in a separate location in the file. This is taken advantage of very cleanly by the ROR system, so that programming web pages has a very "WYSIWYG-ish" feel- Every concept in you web site has a clear, understandable equivalent embodiment in the Ruby code
3. Dynamically detects missing methods- I don't know exactly how it works, but ruby classes are able to know when a method on an object is called at runtime that doesn't exist- So you can essentially enhance the functions an object supports at runtime... this allows Ruby toolkits, such as Rails, to essentially shoehorn their own custom language ideas into ruby (not quite at the level of Lisp's "defmacro", of course)
4. It was scalable from day one- Right from the start, ROR was designed to scale- In fact, it was already part of a commercial app before it even existed as a stand-alone product. This means it already overcame the greatest hurdle of any web-development framework from day one- Most Scheme/Lisp frameworks, for instance, still haven't achieved the level of scalabilty that ROR had right from the start.
5. It has a whiff of that mystical Scandinavian software guru-ism in it that make for seriously powerful software Creating a comprehensive web development system is a messy undertaking- ROR is the product of an obsessive Northern European fanaticism that somehow manages to combine an incredible pragmaticism and also manages to handle all of the many ways that web frameworks fail with the utmost of effectiveness. It isn't brilliant because it makes it easier to do complex things, as other frameworks try to- It's brilliant because it makes things that are already easy so much easier that all the complexity, though still complex, floats to the surface of your code and isn't obscured by the many "easy" parts.
6. No pre-processor Many of the more advanced web-frameworks, as in JAVA, require pre-processing of HTML templates with embedded JAVA- The dynamicity of Ruby makes this step hidden- Explicit preprocessors are practically and cognitively difficult for programmers to deal with.
These, I think, are some of the non-obvious reasons that give ROR the edge over other web frameworks.
Nice comment. Too bad its stolen verbatim from the article AND the summary.
So, for now, it's Java or Python, and associated frameworks for me. But not RoR.
Reading TFA, I wouldn't use words like zealotry or fanaticism to describe either the article or the attitude of the Java programmers it seems to be aimed at. What I do see, though, is a terribly narrow-minded view of programming, and an obvious lack of broader experience. Let's take a few choice quotes.
From the About this series box, before we even get to the article itself:
Surely most of us would agree that any programmer is well-served by familiarity with a variety of languages, programming styles and tools, and by choosing the most appropriate for any given job. Which, despite the absurd claim above, has never been Java in all, or even most, cases.
From the "Hype and skepticism" section:
No-one who's looked into a wide range of programming languages (and I don't mean Java, C++, C# and Visual Basic.Net) would find those claims particularly surprising or implausible. The functional programming world has been outclassing workhorse industrial languages like C++, Delphi, Java and co. in productivity by an order of magnitude for a long time, at least for the kind of application that lends itself to a functional style. So-called scripting languages, which cut away much of the boilerplate baggage required by the workhorses, have proven to be a much more efficient tool for many kinds of project as well, often due to relatively simple features like supporting common data structures as first-class entities.
Moving on to the Rails philosophies, we see things like "Don't Repeat Yourself" being highlighted as "core opinions pervasive within Rails". Surely abstracting common code and data structures into reusable units is a basic principle of sound programming in pretty much any language?
Then we get to the "niche" for Rails:
I'd guess that's wildly optimistic, though it's certainly a common conceit among Java programmers IME. Not everything in the programming world is web-enabled, and much of it has no interest in becoming so either. Why would a high-performance scientific application, a CAD/CAM/CAE package, a FPS or the firmware in your washing machine care about database-backing and Web-enabling?
All-in-all, this seems to be an article aimed at die-hard Java programmers with little experience of the wider programming world. Its arguments support wider exposure to programming and good general programming principles, though it forgets to mention that Ruby on Rails is far from the only way of achieving those ends.
If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
Actually, I think the vast majority of developers out there are far more interested in getting their damn job done, and couldn't care less if Sun GPL'd the Java sources. 'course, you'll never hear that because they're too busy *getting their damn job done*, instead of bitching about licenses on Slashdot.
RoR is a good OS product that helps people solve problems that really bug them. It doesn't - contrary to lot's of other OSS projects - have a website that looks and works like crap . It's lead developers actually have social skills (and running businesses) and can talk coherently in a way that normal people actually understand them. They are tight with the blogging community and are smart enough not to be arrogant and thus convince even the most fanatic Java people to check out their toy. They started the whole webcast thing and built RoR for an actual real life business project they wanted to do (www.basecamphq.com) before going OSS.
Technology wise there is not that much new. Zope is still lightyears ahead of everything else (including RoR) but only last year did their website stop looking and acting like a total pile of doo-doo. Yet still Zope.org's Navigation is somewhat '99ish and much more intimidating and overwelming than the friendly and straightforward RoR Site.
Then there's Django. Which is very neat, partly even better than RoR (and friends with the RoR project), but went OSS a little later than RoR and thus needs to catch up on awareness a little. Symfony is PHPs late answer to the RoR induced MVC frenzy and still to new to gain awareness momentum. CakePHP and P4A seem ok but don't have the marketing stance to be of any significance anytime in the future. They're both so nineties it hurts and thus will wither and die.
Bottom line: RoR are a OSS project that isn't just good at coding or using exotic technologies, they actually have the skill to market it aswell. And they were the first in the framework camp. It's that simple.
We suffer more in our imagination than in reality. - Seneca
Yeah, next thing you know it will try to pluralize "dog" as "dogs" or something crazy and unpredictable like that!
-matthew
"THERE IS NO JUSTICE, THERE IS ONLY ME." -Death
When it comes to Ruby, I have one wish:
.net environment. Performance comparable to C#, developer time comparable to normal Ruby, bytecode obfuscated enough to use in commercial products.
.net to do that, not to mention the programming of that insane compiler, I could write hundreds of useful Ruby programs.
Compile it. For the love of God and all that is holy, Ruby is at least as slow as JavaScript, if not slower -- at least you can compile JavaScript into Java!
Perl6 shows some promise in that area, but I have some serious doubts. Ruby, as a language, does far too many things that simply assume it's a "scripting" language. For instance, it's possible to modify any class at runtime -- thus many core libraries probably rely on that feature. Also, all names in Ruby are kept around at runtime. I'm pretty sure that it actually is doing a hash lookup every time. For instance:
irb(main):026:0> class Fixnum
irb(main):027:1> def method_missing (name, *args )
irb(main):028:2> print 'Attempt to call '
irb(main):029:2> puts name
irb(main):030:2> end
irb(main):031:1> end
=> nil
irb(main):032:0> 5.foo
Attempt to call foo
=> nil
irb(main):033:0>
I'm sure that someone will find a much simpler / more efficient way of doing the above, but the point is the same. Obviously, whenever Ruby executes code that attempts to call '5.foo', or even '5 + 5' (which becomes something like 5.+(5)), it actually stores the code for the call as a call to a given name, and then looks up that name at runtime.
Now, good OO design generally involves making lots and lots of small classes, and even the bigger classes will have lots and lots of small methods. Good programming design in general tells us to refactor mercilessly, which will, in any language, tend to reduce the amount of code per method and increase the number of method calls. And even if you go the other way, and don't use any methods at all, the simplest line in Ruby (since it's a pure OO language) will break down into 5 or 10 method calls, at the very least.
What all this means is, Ruby is back to that old argument of developer time vs. application run time, and I hate that. I really love it when we can break out of that mold -- when we find that, most of the time, a compiler will produce better code than handcoded assembly, or a language-based garbage collector can actually run as fast or faster than a hand-coded, application specific refcounting scheme. Or when we find that Java, despite being bytecode, will, once you JIT it, run as fast or faster than equivalent C++. Or when we find that mod_perl can be close enough to the speed of a C program that it's not even worth considering using C instead.
But when it comes to choosing a language, they all have their performance wrinkles. C++ probably uses more memory than C, and always seems to take far longer to compile. Perl isn't anywhere near as fast as C, so whenever we find something where we need that extra speed, we rewrite chunks of a Perl module in C. Python is the same way, though Psyco looks promising, but Psyco is also x86 only, not even amd64. Java is as fast as anything, once a program starts, which takes far longer than anything else even if you've gcj'd it -- plus, the language sucks compared to Ruby. C# is as fast as Java, and so far seems to load much faster, but the language sucks (really a rehash of Java/C++), IronPython is nowhere near done, and even IronPython isn't as nice as Ruby -- plus, the platform is controlled by Microsoft.
Ruby has absolutely awesome syntax, can be 10x faster to develop in than most other languages, but due to the language design itself, it will always be much, much slower than Perl, and that's saying something. And it's just depressing when you find you can make a chunk of your program run 10x faster by porting from Ruby to C, only it will take 50x more code.
I guess what would make me happy is an insanely intelligent compiler for Ruby, that targeted the
But that's depressing, too, because in the amount of time it would take me to learn enough about Ruby and
Don't thank God, thank a doctor!
The crux of the problem with that argument was brought up by the author of webwork, if I'm not mistaken. If you're coding so much that you really can get a 10x improvment then you're clearly not doing enough design work to be making an app that's worth shit, regardless of the tool. Rails doesn't cut down on the thought time.
DHH kind of tries to disown that comment when he's challenged on it. It's just rails marketing and hype, someone has whispered "10x faster" and they repeat it but they don't stand behind it. One thing that you can bank on, there is a lot of hype around rails, the people who make it are responsible for contributing to that hype and there is very little in the way of concrete information about these outlandish claims.
It's okay at what it does. I personally don't care for the hype and I generally distrust when all you have is hype.
Something else to consider, rails by design scales by pushing everything in to the database. They have some minimal caching at the web tier but none at the db tier. You need to render more pages, buy a bigger database, that's the quick answer and they suggest that it works because "yahoo does it that way" This is kind of an, um, interesting way to address scalability. I like how they make sure that they compare rails to what yahoo does too, it's just a quick and subtle comparison but it works and leads you to believe that you could do something yahoo like in rails, when it couldn't be further from the truth. Activerecord doesn't exactly conserve queries, some fairly simple joins seem to result in a lot of queries and it's kind of heavy. It's sales and marketing's way of saying they haven't really addressed the issue. To be pragmatic about this, why on earth are there all the elaborate caching schemes in EJB and J2EE and JDO? Surely people didn't just think it was something fun to build, I know the rails crowd seems to hate java but don't they think anyone with any real skill worked on it ever? I buy the j2ee is complex argument but I need to understand their argument for the complexity being unneeded. If you're planning to move on to a different project before it actually has to scale, that's not really an argument. From my own experience building clustered j2ee apps, scaling by just shoving everything into the db and hitting it for each page simply isn't a practical option if you have any real traffic.
In fact, every time I look at Ruby, all I see is a pale reflection of Smalltalk. I've yet to see anything new it brings to the table.
.jar files (and the variations on that theme: .war, .ear, etc.) can package up lots of different things, and as long as people know what VM version to run it on, they're good.
Deliverable packaging. Extracting a Smalltalk program from the development environment for distribution is, to be generous, annoying. Which is one of the reasons why Smalltalk works so well in an academic environment, but never caught on for commercial work. Ruby, on the other hand, is about as tough for someone else to deploy as Perl (it isn't).
This is one of the places where Java really changed things and is IMHO, the big reason for why Java has become so popular.
Regards,
Ross
I've used rails for only a few months, but already have quite a good understanding of how everything works, and have even done some hacking/patching on the backend. I've also used ActiveRecord with some applications that are not web-based, all with good success. I love every convention in Rails, except for one, which I dearly hate.
ActiveRecord was designed quite obviously from the perspective of a MySQL user. The train of thought that a DB should only be a place to dump your data and nothing more is extremely prevalent with ActiveRecord. Things like referential constraints on foreign keys are completely ignored/not used, instead being defined in entirety in the model code. Perhaps my biggest aggrivation with ActiveRecord however is that it assumes I implement enumerations as varchar datatypes. I find this just plain wrong. Here's an example:
ActiveRecord way:
CREATE TABLE Users (
id integer primary key,
username varchar,
usertype varchar
);
ActiveRecord will then use its single-table inheritance logic and each subclass of User eg "Administrator" will have that name in the usertype field, stored as a string. From a data-modelling perspective, I find this so wrong. I naturally implement this using an extra table of usertypes and a foreign key in Users:
CREATE TABLE UserTypes ( id integer primary key, type varchar);
CREATE TABLE Users (
id integer primary key,
usertype integer references UserTypes(id)
);
I have managed to get ActiveRecord to play somewhat nicely with these types of constructions by redefining some class methods in ActiveRecord::Base, but I'm definately violating DRY.
This all said, and including the time I needed to spend hacking around in the ActiveRecord code, I am still more productive with Rails. Highly recommended, just with a hint of caution towards ActiveRecord paradigms and database integrity.