REST in Place has never been more than a proof-of-concept for me. It worked, pretty well even, so I never bothered much to develop it further, especially since integrating JavaScript code with Rails apps was a bit of a pain. I did only the barest, necessary maintenance and never actually realized that there are people out there using it.

When Rails 3.1 came out, there was finally a way to properly integrate the code into Rails, so I sat down on a weekend and made some massive changes to REST in Place:

• No more standalone
  Since I don’t think anyone is using it in a different way, REST in Place is now a pure Rails 3.1 gemplugin using the asset pipeline
• Specs
  To facilitate development of new features and refactoring, the app now has a Jasmine spec suite in the testapp. It can be run by visiting http://localhost:3000/jasmine
• CoffeeScript
  Because if you’re not using CoffeScript there’s something wrong with you. It makes JavaScript bearable again.
• Proper CSRF token support
  This was hacky in the past but for a while Rails includes a standard mechanism for providing CSRF information to JavaScript running on the page.
• Automatic detection of include_root_in_json setting in Rails
  Through the magic of erb and the asset pipeline, REST in Place can detect how you’ve configured ActiveRecord.
• BC breaking interface changes
  Two major things have changed that might trip you up:
  • The default css class for REST in Place is now rest-in-place and not rest_in_place.
  • Elements with that default class are initialized automatically on document.ready.
  • The jQuery function to intialize elements with a REST in Place Editor was renamed from rest_in_place() to restInPlace().

All this is now available in a nice gem. All you need to do is add gem 'rest_in_place' to your Gemfile and you’re rollin’ (You might want to take a look into the README first).

Now that I have CoffeeScript and specs, development of new features can be done much faster and easier. Some things I have planned:

• Differentiate between manual abort and a failure
• Validations/proper error responses
• Maybe a nicer set of default widgets and UI improvements
• Rails view helpers

Especially the last two points go a bit against my original intentions for REST in Place, but if it helps more people to use it, hell, why not.

Unfortunately, these changes have come with a very bad timing. One day after I pushed the first beta of 2.0 to github, Ryan Bates did a Railscast about in place editing. While REST in Place is mentioned there, he’s showing Best In Place, a pretty extensive fork of my code that already has most of what I just wrote (asset pipeline, specs) or am going to write (validations, helpers).

Well, as frustrating as that was, I didn’t come as much of a surprise, considered how I’ve neglected REST in Place’s development in the past. I won’t repeat that mistake again, promise.

The definition of forms for editing inline-content is now separated from the Code that deals with Ajax and editing state. This makes it very easy to extend REST in Place with your own Editors.

I also decided to keep the jQuery backwards compatibility for a bit longer.

Check out the changes at http://github.com/janv/rest_in_place.git

In November I got some pull requests for REST in Place which I didn’t get to really have a look at until last week. I haven’t really touched REST in Place in ages and wasn’t really aware that it was that popular. It has 72 followers and 11 forks on github and who knows how many other people are just silently using it! So, I merged in the contributions and dealt with some issues in the tracker and thought about how to go on.

REST in Place originally was a mere proof of concept and one of my first projects in JavaScript and jQuery. I have since written a lot more complicated applications and even a diploma thesis on JavaScript and the old code just isn’t up to my standards anymore. Additionally I have received several pull requests for textarea support which all couldn’t be merged because they were just copypasted and modified a little from the input-tag version. The only solution was a complete rewrite and that’s what I did. While the plugin still works the same way, the code is properly split up and more modular now. This enables easy extension and maintenance from now on and hopefully quicker development from me and better patches from all users.

This new development has some drawbacks too, unfortunately. This massive improvement will only go to the jQuery version of REST in Place. Since I don’t know much about Prototype or mootools, I can’t support both versions anymore. If someone is willing to work with me on this, I’ll happily accept their contributions but I can’t do this on my own. If anyone is willing to do so, please reply in the comments, so we can work out a plan. I want to keep all three versions as similar as possible, this means the Prototype and mootools versions should follow the same object-oriented structure as the jQuery version.

One last thing: I will support jQuery < 1.4 until 1.4.1 comes out. 1.4 introduced some very nice changes which I’d like to make use of but since 1.4 seems a little buggy still, I’ll continue to support the older versions for a little while.

Ende 2007 habe ich bei 9elements einen Crashkurs zu Ruby on Rails gegeben. Da mich inzwischen schon mehrere Leute gefragt haben ob ich die Folien nicht mal rausgeben möchte, tue ich das jetzt. Die Folien sind absichtlich so gestaltet, dass sie auch ausserhalb des Vortrags als Nachschlagewerk für Ruby dienen können. Der Rails-Teil ist ein wenig arg knapp gehalten und kann vor allem einen groben Überblick in den Aufbau des Frameworks geben.

Ruby & Rails Extremcrashkurs (PDF-Link) v1.0 27.03.09

I tried to spark interest in Rails and Ruby and judging from the first comments I think it worked :)

The text released today is only the first part, covering just enough Ruby to understand the second part coming out next week. If you like the article, please digg it or promote it on reddit/delicious/slashdot.

I fixed that problem yesterday in both the jQuery and the Prototype version (both included in the plugin.)

Check it out on the REST in Place project page.

• Domain-code in your controllers instead of your models
• Rails choice of inheritance (AR as a base class for models) for implementing AR

Putting domain code inside your controllers is a programmer problem, not a framework problem. I won’t even elaborate this any further.

The other issue is trickier. Not because of technical issues but because there’s a problem with the perception of Rails ActiveRecord. I first didn’t even want to waste my time to write this rant but then I started a comment on one of the postings that turned longer and longer until I decided to make a post of it.

Bill Karwin wrote some observations that I can mostly agree with. There’s one exception though: I don’t see any problem with AR being implemented as a base class for your models.

One perceived problem is a lack of separation of concerns, the idea that you should separate model logic and database logic and that ActiveRecords fails here.

But one must look beyond the separation-of-concerns dogma here and ask what motivates this principle. Mixed concerns lead to confusion, confusions leads to errors and redundance (and thus to more errors). So, the motivation is to maintain a clear view over your methods and to reduce redundance.

Both goals are maintained by Rails although the models contain a mix of model- and database logic. Because most things can be expressed very concisely in Ruby, one line or even no code at all (using the powers of reflection) is enough to achieve what you want. If all your model-functionality and ORM-functionality fit within one page on your screen, the benefit of splitting both into separate modules and/or files becomes too low to justify the cost.

The second problem with inheriting your models from AR::Base is supposedly the tight coupling between your model and your DB-access layer, requiring you to have a database ready for unit testing. If you’ve ever written tests for Rails, you know this is bullshit. Testing is a non-issue and the support for the testing database so seamless that I can’t imagine it being any more simple. One rake task sets up your testing database after a migration, the rest is handled automatically.

Pretending that relying on AR so much for your models is still bad somehow because you might want to change your record-store a some point in the lifetime of your application is nothing but a bunch of bullshit. NO solution EVER will enable you to do THAT in a way that’s so seamless that you’d want to. We’re talking about software here, not lightbulbs that you just screw in. Abstractions are always leaky and talking as if they were not is foolish.

The whole point is that Rails set out to to one thing well, and that is to write web apps in a certain way that has proven to be quite productive and covering the needs of most projects pretty well. You get a lot of comfort following that way but you pay a price if you don’t, namely losing that comfort. People are demanding stuff that Rails never promised to deliver. About their motivations I can only speculate. Maybe they’re just clueless, maybe they just want to make some noise. In any way, they’re hell of a reason to stay away from Digg and Reddit and stick to some bloggers you trust with not wasting your time.

1. Through a dumb count as soon as you query the collection for its size.
   This doesn’t require any additional work but puts quite a load on the database as soon as you have a large list of objects and want to know the size of an associated collection for each object. For 100 posts with comments, this approach would query the database 100 times with SELECT count(*) AS count_all FROMcommentsWHERE (comments.post_id = 1234). This might be okay for single objects which are queried from time to time but not for collections that need to be displayed frequently.
2. Through counter caches that are a bit of a pain in the ass to set up correctly and gave me the fishy impression that they are easily corrupted. Now, I admit that I didn’t spend too long investigating the implementation of the counter cache but after fiddling around with it for an hour before I finally found out how to properly initialize the cache in my migration and after discovering that the cache can only be changed relative to its current content, I left with a bad feeling.
   All this hassle is absolutely unavoidable if you need maximum performance. In this article I’ll use blogposts and comments as an example, though only because this is familiar to many people. A real blog with a bunch of posts on its index page, receiving any considerable amount of hits per day is a bad candidate for the trick I describe here.

In raw SQL, if you want to find out the amount of associated rows in a different table, you use a JOIN, combined with COUNT() and GROUP BY, like this:

Admittedly, this is slower than a counter cache but is not as difficult to set up, doesn’t risk errors due to a corrupt cache and if you chose your database keys wisely it is a pretty nice compromise. When you ask an association collection for its size(), rails checks for the presence of a counter cache attribute in the current ActiveRecord object. If it finds one, it uses its content to return the collection size, otherwise the database is queried.

The catch is now, that in the above example, we inserted a perfectly valid counter cache column into our posts without specifying caching in the association declaration in the class. ActiveRecord inserts that columns content into a comments_count attribute in our Posts but since it doesn’t know exactly what to do with it, it doesn’t cast it into an integer but leaves it in there as a String. That makes size(), or to be more precise, the count_records() method trip with a “String can’t be coerced into Fixnum” error.

To fix this, I wrote an extension for the has_many Association:

Uh, well, yeah, the only change here is the .to_i at the end of line 4 but hey, what did you expect?

Save that in lib/optional_join_counter.rb and extend your association with has_many :whatevers, :extend => OptionalJoinCounter

Now, to get back to the example, imagine we want to use this trick to count our comments. The above SQL can either be written by hand, or with Rails finder options:

Well, after a day playing around with jQuery, I present REST in Place