Rolling With Ruby On Rails

Bart Braem writes "The Ruby community is abuzz about Rails, a web application framework that makes database-backed apps dead simple. What's the fuss? Is it worth the hype? Curt Hibbs shows off Rails at ONLamp, building a simple application that even non-Rubyists can follow."

Comments

Played with it

[tenchiken]

And did a quick application with Ruby on Rails already. If you are confortable with Perl, you may find this easier to deal with then Python and it's love of whitespace. The object model is much more developed then either python or perl, but it still retains much of the flexability of the other two systems.

Ruby has already inspired a few efforts to duplicate the technology in Java and in .NET. Since the core technology behind RoR is open classes, and the ability to add accessors and functionality on the fly, the other languages just don't cut it.

The usual warnings apply. Implicit code is easier 90% of the time, but that other 10% is painful to debug. With large projects you can prototype fast, but maintaining may be much more difficult.

Re:Played with it

[Merk]

Once you get used to the idea of passing blocks of code around, you'll love it, and won't be able to go back to Python... er... I mean, won't be able to go without it.

The canonical example is the iterator. Given an array pets containing ["dog", "cat", "fish"]:

pets.each { |pet| puts pet }

Will return
dog
cat
fish
If you want to print out the uppercase versions

pets.each { |pet| puts pet.upcase }

Or if you want to add some text:

pets.each { |pet| puts "I love my pet #{pet}" }

Big deal, right? Not much different from a for loop. But blocks are amazing when dealing with things like a database. You can put all the setup, teardown and error-handling code in a method that's hidden from the user, and all they have to do is pass in the block they want the DB object to execute:

require 'dbi'

DBI.connect('DBI:Mysql:test', 'testuser', 'testpwd') do | dbh |

puts "inserting..."
sql = "insert into simple01 (SongName, SongLength_s) VALUES (?, ?)"
dbh.prepare(sql) do | sth |
1.upto(13) { |i| sth.execute("Song #{i}", "#{i*10}") }
end

puts "selecting..."
dbh.select_all('select * from simple01') do | row |
p row
end

puts "deleting..."
dbh.do('delete from simple01 where internal_id > 10')

end

Unfortunately, slashdot eats my indentation, but fortunately, Ruby not being as picky about whitespace as *some languages*, that doesn't matter. Note that all that code is wrapped in a DBI.connect() call, which connects before it starts executing the block, and disconnects after. There's no "close" call required, it's all wrapped up for you.

Useful Ruby Online Resources (categorized)

[Anonymous Coward]

A categorized collection of ruby links can be found here in a nicer format:

http://www.rubygarden.org/ruby?RubyOnTheNet

Interactive ruby resources:

irc://irc.freenode.net/ruby-lang - the #ruby-lang channel is popular. More info at RubyOnIRC

http://www.ruby-forum.org/bb/ - a forum for ruby novices to ask questions

news://comp.lang.ruby - the ruby newsgroup

Ruby websites:

http://www.ruby-lang.org/ - ruby home

http://www.ruby-doc.org/ - ruby docs and online reference

http://www.rubyforge.org/ - rubyforge ruby projects

http://raa.ruby-lang.org/ - ruby application archive

Ruby Code Examples and Snippets:

http://pleac.sourceforge.net/pleac_ruby/ - ruby pleac

http://www.rubygarden.org/ruby?RubyOnlineCookboo k - ruby cookbook

Popular ruby and ruby-related projects:

http://rubyinstaller.rubyforge.org/wiki/wiki.pl - ruby installer for Windows

http://rubyforge.org/projects/rubygems/ - rubygems ruby package manager

http://www.yaml.org/ - ruby 1.8 includes built-in yaml support

http://www.rubyonrails.com/ - web framework in ruby

http://rubyforge.org/projects/instiki/ - wiki in ruby

Re:Good for "recipe" queries but little else

[Minam]

You might want to tell that to Basecamp, 43 Things, and Tada Lists, since they obviously have no idea that Rails isn't good for anything of that magnitude. Might also mention it to all the thousands of people that use those sites, daily, and to the handful of developers who built and deployed those sites in a fraction of the time and cost of other web solutions.

Then again, maybe you shouldn't...

Rails is just the tip of the iceberg

[Paradox]

Rails is an incredibly good framework for Ruby, that really shows off its power and makes it easy to get a web application going, but it's not all that Ruby has to offer.

Ruby is full of incredible libraries and frameworks like this, especially where text processing and web development are concerned. It's because Ruby has such a rich set of features.

Anyone who likes Rails should dig deeper. Heck, Ruby's standard library comes with some amazing things. Ruby also has a framework called RubyGems,
which is very much like Perl's CPAN integration or CommonLisp's ASDF framework.

Have you ever programmed a web app before?

[Paradox]

Well, most of the article is setup. But I do agree the article is less than a stunning demo of rails. Instead, you might want to fire up the video at www.rubyonrails.com which walks you through a 10 minute application build.

It's extremely cool to watch someone set up a working webapp that fast.

But I have to take issue with:

Take a look at this example. It's incrediblyl complicated and all it does is display a horrible little form that lets you query cookbook recipies!

Half of the darn article is setting up MySql and installing Ruby and Rails from scratch on a windows machine. Do you have any idea how much harder this crap is to write in other frameworks? You'd have to write at least 2x as much code. No one has an Active Record class as good as Rails'. You'd double the code count just doing the SQL linkage!

It's one thing to be unimpressed, but it's another to know jack shit about the domain and say it's all worthless. Anyone who's ever made a web application will appreciate it.

Re:Okay, so what else does it do?

[swimmar132]

Perhaps the documentation for ActiveRecord will help answer your question?

http://ar.rubyonrails.org/

You can automatically retrieve data from the database in the form of an object, do manipulations or calculations, display it, modify it, then do a save() method on the object and it'll go right back into the database.

It's not so bad, Rails is unit tested very well

[Paradox]

Firstly, Rails's ActiveRecord class is very simple Ruby code, so it's naturally bug-resistant.

Secondly, the author knows that ActiveRecord could be a source of problems, which is why it's got dozens of unit tests, covering nearly every line of code.

Thirdly, even with all that bugs can and will sneak through, which is why ActiveRecord can, upon command, write a detailed log of its attempt to dynamically bind and create the classes you want. The logging is at the message-passing level of Ruby, which is nearly as atomic as you can get (you could hack the interpreter to go further, but that'd be pointless).

The dark ages of hideous bugs in dynamic code are gone my friend. We have the tools and techniques to make code of this type both safe and maintainable. Don't be afraid of it.

weird directory structure

[drew]

i've tried rails a little bit, and jsp before that, and wasn't particularly impressed with either. is there a reason all web frameworks require a weird directory structure? rails seems better then jsp because it doesn't require an arcane descriptor file, but it still requires you to use a funky directory structure, which means the structure of your application doesn't seem to correspond in any meaningful way with your web site structure.

why can't someone build a decent framework that follows the simple "directories are directories and files are pages" model used by asp, php, cgi, etc.

and what's with the database naming conventions? the author kind of brushes it off at the end with this statement: "Even if you have to use a legacy database that does not use the Rails naming conventions, you don't have to give up the productivity advantages of using Rails--there is still a way to tell Rails explicitly what table and column names to use." personally I would not use those conventions no matter what database i was using, nor would any decent database developer or administrator i have ever known.

at any rate, at work i program in whatever language they tell me- currently asp+jscript, before that php. for personal projects, my current favorite is perl's HTML::Mason. all the benefits of php (and then some) without the awful language conventions.