I would like to have a new method for Date class in my Ruby 2.0 Rails 4 application. Adding a new like 'date_extensions.rb' in /lib used to work in another Ruby 1.9 Rails 3.2 app but not here. The extension is pretty simple now:
class Date
def week_day
self.wday == 0 ? 7 : self.wday
end
end
I do not like to put it in initializer as it keeps growing. Is there a good workaround?
At some point, Rails stopped adding the lib directory to the autoload paths. The other app had probably set a setting to autoload the lib directory and your new app doesn't have that (yet?). So that's why you're having to require the file directly via an initializer. For what it's worth: I think this is the better approach -- only load code when you need it. I usually add a config/initializers/application.rb and then add requires such as require "date_extensions" in there. Then the date_extensions.rb file goes in the lib folder as you suggest.
Related
I want to build an index for different objects in my Rails project and would like to add a 'count_occurences' method that I can call on String objects.
I saw I could do something like
class String
def self.count_occurences
do_something_here
end
end
What's the exact way to define this method, and where to put the code in my Rails project?
Thanks
You can define a new class in your application at lib/ext/string.rb and put this content in it:
class String
def to_magic
"magic"
end
end
To load this class, you will need to require it in your config/application.rb file or in an initializer. If you had many of these extensions, an initializer is better! The way to load it is simple:
require 'ext/string'
The to_magic method will then be available on instances of the String class inside your application / console, i.e.:
>> "not magic".to_magic
=> "magic"
No plugins necessary.
I know this is an old thread, but it doesn't seem as if the accepted solution works in Rails 4+ (at least not for me). Putting the extension rb file in to config/initializers worked.
Alternatively, you can add /lib to the Rails autoloader (in config/application.rb, in the Application class:
config.autoload_paths += %W(#{config.root}/lib)
require 'ext/string'
See this:
http://brettu.com/rails-ruby-tips-203-load-lib-files-in-rails-4/
When you want to extend some core class then you usually want to create a plugin (it is handy when need this code in another application). Here you can find a guide how to create a plugin http://guides.rubyonrails.org/plugins.html and point #3 show you how to extend String class: http://guides.rubyonrails.org/plugins.html#extending-core-classes
I ran into a problem with adding a method to String that allows you to do something like: "9".is_a_number? and get true or false. I tested it working on development but when I pushed to production it didn't work.
Anybody have experience changing Ruby core classes on Heroku?
Both times I placed the new code inside the /helper directory on my Rails app.
Edit:
This is from my memory so I don't have 100% confidence that this is what I had:
app/helpers/sudoku_helper.rb
class String
def is_a_number?
self.to_f.to_s == self.to_s || self.to_i.to_s == self.to_s
end
end
I didn't add anything else, as it worked on development. Perhaps I need to do something to tell Rails to run it on production?
Put your code in the lib folder and require it in a initializer or directly put your code in the initializer.
This way, you can be sure it is loaded and when is it loaded.
I'm trying to add a method to the DateTime class like so:
class DateTime
def ymd(sep = "/")
strftime("%Y#{sep}%m#{sep}%d")
end
end
I put this in #{config.root}/lib/datetime.rb and updated the autoload_path to include #{config.root}/lib (since that seems to go in and out of the conventional autoload path). That didn't work, so I also tried putting it in a random directory (#{config.root}/blah and added that path to the autoload_paths line in the config).
In all of the above cases, I'm only able to use the new method in the rails console if I require 'datetime' first, and I'm not able to use it in controllers or view templates no matter what I do.
So,
Should the file be called datetime.rb or date_time.rb? (I've tried both so far and neither are currently working)
Where should I be putting this file so I can use the new method in models, controllers and views?
Any idea why I can require it in the console, but it doesn't autoload there?
The app is currently running rails 3.2.21, but I'll switch to rails 4 at some point so answers for either version are appreciated.
Using Rails 3.2 and ruby 1.9.3p0
I am trying out the gem delayed_job. I have created a file lib/mailing_job.rb in which I have class MailingJob.
In a controller under app/controllers/requests_controller.rb I am calling
job = MailingJob.new(#request)
but this is returning the error
uninitialized constant RequestsController::MailingJob
I think it is because I need a proper way of referencing a class under a different folder structure.
Any idea how I can isntantiate class MailingJob from a different file (class) in a different folder?
Rails 3 does not include the lib folder within the load path so your application does not know how to find the class.
You can modify config/application.rb and add a line to instruct rails to also look in the lib folder like so
config.autoload_paths += %W(#{config.root}/lib)
In an initializer (e.g. config/initializers/delayed_job.rb), do this (doesnt matter where)
require 'mailing_job'
So there's this great plugin I've gotten used to using in my Rails 2 projects called Bootstrapper. It essentially duplicates the functionality of the seeds.rb file, but I like it because it lets you break up your bootstrap process into concise chunks.
Anyway, I've gone so far as to fork the project and attempt to turn it into a Rails 3 gem. I've been able to get the gem to initialize and register the rake tasks and generators OK. However, I'm running into a problem with the Bootstrapper class itself. It won't load in the Rails project unless it's in a module.
That is, if I place the Bootstrapper class in a file by itself and require that file in my Railtie, then in my Rails app, it can't find the Bootstrapper class. If I put the class in a module and call Bootstrapper::Bootstrapper everything is peachy.
The code that actually requires the Bootstrapper class is this:
ActiveSupport.on_load :active_record do
require 'bootstrapper/bootstrapper'
end
The source is available here:
http://github.com/jrmehle/bootstrapper/tree/make_gem
Autoload paths actually has an annoying feature of following filesystem paths. For example in your lib or extras (depending on what you autoload) you might have the following file structure:
lib/bootstrapper/bootstrapper.rb
# in this case, Bootstrapper::Bootstrapper.class = Class in rails c
# ie: you don't get a NameError exception
More specifically,
lib/bootstrappers/bootstrapper.rb
# Bootstrapper::Bootstrapper => NameError
# Bootstrappers::Bootstrapper => works
If you really want the other way, you can move everything into your lib/bootstrapper.rb source file but meh, I don't like doing that, that's not how gems are organized. In rails3, you'll find the autoloading pretty nice once you use modules everywhere (which can be painful).
Rails3 uses /extras instead of /lib but it's not required, it's just the default (commented out) from rails new. To switch, you just autoload extras instead of lib.