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Posted by Dmytro Shteflyuk on under Ruby & Rails
There are couple of cheat sheets about Ruby on Rails and related technologies can be found in the web. I decided to collect all of them (almost all) in one post just to keep them in mind. All of them are in full color PDFs or PNGs.
Posted by Dmytro Shteflyuk on under Ruby & Rails
My friends often asked me how to upload file using AJAX, and usually they got answer “in no way”. Correct answer, but what if I need to upload file without full page reloading? And, of course, I want to use RJS in this case. Here I’ll explain what to do to get effect very similar to AJAX file upload (btw, Gmail uses this technique).
Posted by Dmytro Shteflyuk on under Ruby & Rails
In my current project based on Ruby on Rails framework, I need to store application specific configuration somehow. There are several approaches I’ve found in Internet: AppConfig plugin, several methods described on the HowtoAddYourOwnConfigInfo wiki page, but neither one looks “config-like”. Me with my friend, Alexey Kovyrin, discovered all of them and decided to use YAML-file as a configuration format. In my opinion, the ideal configuration file looks like this:
1 2 3 4 5 6 7 8 9 10 11 | common: support_email: [email protected] root_url: myhost.com photos_max_number: 6 production: email_exceptions: true development: root_url: localhost:3000 photos_max_number: 10 |
In this example you can see three sections: common will be used as a base configuration for all environments, production and development — environment specific options. Optional sections are production, development, and testing, or any other custom environment name. I’ve placed this file in config/config.yml and created lib/app_config.rb which looks like this:
1 2 3 4 5 6 7 8 | # Load application configuration require 'ostruct' require 'yaml' config = YAML.load_file("#{Rails.root}/config/config.yml") || {} app_config = config['common'] || {} app_config.update(config[Rails.env] || {}) AppConfig = OpenStruct.new(app_config) |
Now I’m able to use constructions like AppConfig.support_email and AppConfig.root_url. Looks like I’ve kept all my configs as DRY as possible :-)
Posted by Dmytro Shteflyuk on under Ruby & Rails
Great news, guys! Apache 2.2 is in unstable now. I was very discouraged when tried to do apt-get install apache2-utils and it proposed me to remove apache2 and install it again :-) I decided to install new version to test rails with Apache 2.2, mod_proxy_balancing and mongrel. In this post I’ve described my adventures (or misfortunes?)
Posted by Dmytro Shteflyuk on under Ruby & Rails
Yesterday in mailing list of russian RoR group we have discussed following problem. MySQL database has unique index and model has validates_uniqueness_of constraint. Do we need to handle MySQL server exceptions or RoR’s validation will be enough?