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5 quotes by the creator of PHP, Rasmus Lerdorf: I don’t like programming, and I’m not a real programmer.

studpete — Sat, 17 Apr 2010 21:49:59 +0000

I really don’t like programming. I built this tool to program less so that I could just reuse code.
PHP is about as exciting as your toothbrush. You use it every day, it does the job, it is a simple tool, so what? Who would want to read about toothbrushes?
I was really, really bad at writing parsers. I still am really bad at writing parsers. We have things like protected properties. We have abstract methods. We have all this stuff that your computer science teacher told you you should be using. I don’t care about this crap at all.
There are people who actually like programming. I don’t understand why they like programming.
I’m not a real programmer. I throw together things until it works then I move on. The real programmers will say “yeah it works but you’re leaking memory everywhere. Perhaps we should fix that.” I’ll just restart apache every 10 requests.

+1 for Ruby!

25 Best Programmer Comics

Compress JavaScript with YUI Compressor

studpete — Tue, 20 Oct 2009 14:18:07 +0000

JavaScript files that are served to the user should be compressed and minified, and ideally everything packed into ONE big file. You can do this with some rails plugins (not tested so far), or using the “manual” way of compressing it yourself. (or download a compressed file

I worked with YUI Compressor on compressing a fresh git clone of jqGrid.

From Yahoos developer page:

The YUI Compressor is written in Java (requires Java >= 1.4) and relies on Rhino to tokenize the source JavaScript file. It starts by analyzing the source JavaScript file to understand how it is structured. It then prints out the token stream, omitting as many white space characters as possible, and replacing all local symbols by a 1 (or 2, or 3) letter symbol wherever such a substitution is appropriate

This is a typical call:

java -jar yuicompressor-2.4.2.jar --charset=utf-8 -o dist\jquery.jqGrid.min.js jquery.jqGrid.js

With jqGrid, you have many js files that need to be merged together. You can do this manually (sucks) or with some kind of script. For jqGrid, pbor provides an ANT script. Copy yuicompressor, build.xml and build.properties in jqGrid source, change build.properties to mach the yui path (mostly YUICompressor=yuicompressor-2.4.2.jar) and start it via shell> ant.

Voila! Your minified jgGrid is waiting in the dist\ folder for you.

Update: In the tqgrid36 branch, build.xml and build.properties are already there. So you just have to modify the .properties to match your yui path.

ant

No related posts.

BigOldRailsTemplate

studpete — Tue, 20 Oct 2009 09:42:17 +0000

Playing around with BigOldRailsTemplate.
There are (in the full sense of the word) many gems that I didn’t know about.

What templates do you use for rails dev?

Rails + Google App Engine !?

Database transfer with taps

studpete — Wed, 30 Sep 2009 10:10:00 +0000

Stumbled on another essential tool for rails development, taps!

Let you sync your server database with the local one with a breeze!

On the server:
taps server mysql://root@localhost/mydb tmpuser tmppass

On the client:
taps pull mysql://root@localhost/mydb http://tmpuser:tmppass@slicehost-box:5000

This can be done vice-versa, much better than a mysqldump! And it works even with different databases!

Rails + Google App Engine !?

studpete — Tue, 29 Sep 2009 19:54:32 +0000

Today I experimented with a few friends how well Rails runs on Google’s App Engine.

App Engine for itself works with python and java, rails works via jruby.
The conditions are great, and for small apps googles engine is free.

But there are several drawbacks. BigTable, googles database does NOT WORK with ActiveRecord. I believe AR is one of the core features of rails. In edge rails, there is the possibility to switch your OR mapper to Data Mapper, an alternative (maybe faster) approach to ORM, which actually has BigTable-Mappings. BUT – DM does not play nicely with JRuby, at least for our experiments it didn’t work out.

And you loose one of rails biggest advantages, the plugins. All those acts_as_ stuff is made for ActiveRecord and not for DM.

So the App Engine is no alternative, except if you want to go through great pain. Maybe this changes when Data Mapper becomes more mature, and Rails 3 is released. Meanwhile, you’re better of with other hosters.

Try Heroku. They let you deploy your rails app within a git push. And the’re free for starting a small app!

Pitfalls with Ruby’s Integer-Constructor

studpete — Thu, 30 Jul 2009 10:03:35 +0000

Got an strange error:

[CC]
invalid value for Integer “09″
[/CC]

What did I do? (…)Integer(somestring)(…) where somestring was something between 01-99.
Turns out that an leading zero tells ruby that this is octal. Hell, I don’t have any octal stuff in my web app.

Solution: Do it the ruby way, use .to_i – even cleaner, and no octal nonsense

(Why I posted this? Because I never got that error, only after hitting production mode, someone committed a 09. Pretty everything else is parseable, 00-07 is valid octal)

Here is the source.

Demystifiying Rails Model attributes overriding

studpete — Tue, 28 Jul 2009 14:43:17 +0000

In the java world, you have setter and getter in your model which are called ALWAYS. Change some behaviour in the setter/getter and you are done. Things are somewhat more complicated if we look at rails and activerecord.

Imagine you have a model that should parse both minutes and a formatted hour/minute string as data:
[cc lang="ruby"]
testcase.estimated_time = “90″
testcase.estimated_time = “01:30″
[/cc]
As the data is saved as integer in minutes, some conversion has to be done to parse the second string. To get this right, it should be done in the model itself (as we may have various places in our web app where it can be edited)

My first try was to simply override the setter and getter in the model:

[cc lang="ruby"]
# THIS DOES NOT WORK!

def estimated_time
self['estimated_time']
end

def estimated_time=(_estimated_time)
self['estimated_time'] = _estimated_time
end
[/cc]

Well, u can assume that this doesn’t work. Why? The setter is not always called in rails – only if you directly adress estimated time, but NOT if you update a bunch of attributes (which is the normal way on a post update)

Solution

ActiveRecord defines the estimated_time= method on the testcase class itself.
There is a technique called “methode chaining”, but this only works for associations.

The best way to go is by using a virtual property.

[cc lang="ruby"]
def estimated_time_string
helper.format_time self.estimated_time, “”
end

def estimated_time_string=(_estimated_time)
self.estimated_time = convert_time(_estimated_time)
end
[/cc]

Change your forms to use estimated_time_string instead of estimated_time.

Rails has_many and dynamic conditions

Add a version timestamp with capistrano

studpete — Wed, 15 Jul 2009 13:21:14 +0000

If you want to show _when_ the app has been deployed with capistrano, this snipped might come in handy:

############################################################# # Custom Tasks #############################################################


set :version_file, "#{tcdb_path}/app/views/layouts/_version.html.erb"
namespace :my_tasks do

desc "Sets the timestamp in version_file"

task :set_version_info do

run "rm #{version_file}"

run "echo '#{Time.now}' >> #{version_file}"

end

end

after 'deploy:symlink', 'my_tasks:set_version_info'

One more thing… add this file to your layout (the footer is a good place for it)
< %= render :partial => '/layouts/version' %>

Capistrano – Deploying 2.0

Capistrano – Deploying 2.0

studpete — Wed, 15 Jul 2009 09:59:54 +0000

…because ssh’in and updating all this code manually is so 2006.

Enter Capistrano! It’s for web what make is for c. It’s simple, widely used and even those php kids begin likein’ it!

A tool which make subsequent deployments to your webserver much easier.

Installation

Capostrano runs on your machine. You don’t need it on your server to work!

[CC]

gem install capistrano

[/CC]

‘Capistranize’ your application

[CC]

capify .

[/CC]

Then setup the config/deploy.rb file. There are many guides on the net.

Deploy your app

cap deploy:setup # creates directories on the server cap deploy:cold # copies code + db migration cap deploy # update code (normal call)

Capistrano + local git repo

deploy.rb:

set :repository, "file:///file/localrepo.git" set :scm, :git set :branch, "master" set :deploy_via, :copy

The “copy” deployment strategy is the only working one, as your server does not has direct access to your repo. If you have a possibility to remote-upload the repo, do so, and choose the remote_cache strategy, which is much faster.

My config

############################################################# # Application ############################################################# set :application, "app" set :deploy_to, "/var/www/#{application}_src"


#############################################################

#	Settings

#############################################################
# we don't have sudo rights

set :use_sudo, false
# set to production environment

set :rails_env, 'production'
#############################################################

#	Servers

#############################################################
set :user, "user"

set :domain, "server"

role :app, domain

role :web, domain

role :db, domain, :primary => true
#############################################################

#	Git

#############################################################
# we are using a local copy of the git repository

set :repository, "file:///..........git"

set :scm, :git

set :branch, "master"

set :deploy_via, :copy
#############################################################

#	Override Tasks

#############################################################
namespace :deploy do

  task :finalize_update, :except => { :no_release => true } do

    logger.info 'do nothing - overridden finalize_update'

  end
  desc "Restarting mod_rails with restart.txt"

  task :restart, :roles => :app, :except => { :no_release => true } do

    run "touch #{current_path}/tmp/restart.txt"

  end

[:start, :stop].each do |t| desc "#{t} task is a no-op with mod_rails" task t, :roles => :app do end end end

Links

http://capitate.rubyforge.org/recipes/deploy.html

http://www.softiesonrails.com/2007/4/5/the-absolute-moron-s-guide-to-capistrano

http://github.com/guides/deploying-with-capistrano

The Capistrano Peepcode Screencast

http://jimneath.org/2008/05/10/using-capistrano-with-passenger-mod_rails/

Freezing your Rails version/gems!

studpete — Tue, 14 Jul 2009 08:32:12 +0000

Ever wondered what “freeze your gems” is all about?

Most rails app depend heavily on gems (rails itself is a gem!) and we somehow need to make sure that everything works together. And you really should care about this.

Update all your gems

[CC]
sudo gem update
[/CC]

New gem updates may make backward incompatible changes that breaks the code. So freezing a gem puts it into the vendor folder of the application and will not updated on its own. Rails first looks into /vendor/rails before searching everywhere else for your gems.

Freeze your rails app

Happy us – there’s a rake task that does all the hard work!

[CC]

rake rails:freeze:gems

[/CC]

Freezing now copies unpacks rails into this special folder.

There’s also a “rake rails:unfreeze” – command, but if you simply wanna freeze your updated rails gems, run the freeze-command again.

Manage your dependencies

To freeze your gems, you need to tell rails what you need. Therefore use the gem dependency feature of Rails 2.1+. Edit config/environment.rb

If you don’t know what you require, read the full list via gem list.

[CC]
Rails::Initializer.run do |config|
…
# Require the latest version of haml
config.gem “haml”
config.gem “thoughtbot-factory_girl”,
:lib => “factory_girl”,
:source => “http://gems.github.com”
…
end
[/CC]

You can require a specific version or the latest (omitting the :version parameter); custom sources are also possible via :source => (e.g. the gems.github.com stuff)

Now tell rake that you want to install those gems (they should be installed anyway)

[CC]
rake gems:install
[/CC]

Freeze your gems

Next, we wanna freeze the gems too. The are copied into /vender/gems

[CC]
rake gems:build
rake gems:unpack:dependencies
[/CC]

The build command makes the native extensions.

Get the list of your gems

[CC]

rake gems

[/CC]

The ‘F’ shows your freezed gems.

Note

There are some gotchas however: Gems with native extensions(libxml…) can’t be frozen, as the OS code needs to live in the external OS.

Links

http://ryandaigle.com/articles/2008/4/1/what-s-new-in-edge-rails-gem-dependencies

http://stackoverflow.com/questions/799416/whats-the-point-of-freezing-your-rails-version-gems

http://www.softiesonrails.com/2008/1/3/freezing-your-rails-application