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'
Related
In one of my controllers I would like to use a Service-Class that I located inside of: services/cars/strategies/unload_car_strategy.rb
Although the unload_car_strategy.rb is located inside the folders, I don't want to use namespacing: The class right now looks like this:
class UnloadCarStrategy
....
end
When I call in my controller UnloadCarStrategy.new I get the error:
NameError: uninitialized constant UnloadCarStrategy
How can I instruct Rails to load this Class?
By default everything under your app/ dir gets auto- and eager- loaded when your application starts. So you got your services dir loaded when the application started.
Even though if you add as many folders and files in those folders you want, Rails will load them for you until you follow the namespacing.
Since you are not using the namespacing the class UnloadCarStrategy doesn't get loaded.
You have to explicitly require it either in the respective controller where it is needed or in the application.rb file.
you either add
require "#{Rails.root}/app/services/cars/strategies/unload_car_strategy" in the controller from where it has to be called
or add the below line to application.rb
config.autoload_paths += %W({config.root}/app/services/cars/strategies/unload_car_strategy.rb)
source : https://gist.github.com/maxim/6503591#if-you-add-a-dir-under-appsomething
THE SHORT VERSION: How do I tell Rails to autoload an ActiveRecord class called ClassName that isn't located in the default location (app/models/class_name.rb). E.g. what if it's in app/models/subdirectory/class_name.rb and I don't want to rename the class to Subdirectory::ClassName?
THE LONGER VERSION:
I know that, by default in Rails, my class names have to follow a specific structure for Rails to be able to autoload them.
E.g. If my class is called Person, if I put it in app/models/person.rb, Rails can load it fine, but if I put it in e.g. app/models/person_class.rb, it can't. If I namespace it, e.g. Humanity::Person, I need to put it in the right folder app/model/humanity/person.
(Plus I can put classes in lib but I'll leave aside that detail for now)
So far so good. But what happens when I have a ton of ActiveRecord classes clogging up my app/models folder and I want to logically organise them into directory, but don't want to rename or namespace the actual classes? How can I tell Rails to autoload this classes?
Or is there a good reason why I shouldn't do this?
Add this line to config/application.rb
config.autoload_paths += Dir[Rails.root.join('app', 'models', '{**/}')]
Then you can use your model with their name as it is without name-spacing.
I'm having a problem with a module name and the folder structure.
I have a model defined as
module API
module RESTv2
class User
end
end
end
The folder structure looks like
models/api/restv2/user.rb
When trying to access the class, I get an uninitialized constant error. However, if I change the module name to REST and the folder to /rest, I don't get the error.
I assume the problem has to do with the naming of the folder, and I've tried all different combos of /rest_v_2, /rest_v2, /restv_2, etc.
Any suggestions?
Rails uses the 'underscore' method on a module or class name to try and figure out what file to load when it comes across a constant it doesn't know yet. When you run your module through this method, it doesn't seem to give the most intuitive result:
"RESTv2".underscore
# => "res_tv2"
I'm not sure why underscore makes this choice, but I bet renaming your module dir to the above would fix your issue (though I think I'd prefer just renaming it to "RestV2 or RESTV2 so the directory name is sane).
You'll need to configure Rails to autoload in the subdirectories of the app/model directory. Put this in your config/application.rb:
config.autoload_paths += Dir["#{config.root}/app/models/**/"]
Then you should be able to autoload those files.
Also, your likely filename will have to be app/model/api/res_tv2/user.rb, as Rails uses String.underscore to determine the filename. I'd just call it API::V2::User to avoid headaches, unless you have more than one type of API.
I'm working on a Rails 3 application (specifically 3.2.13) on ruby 1.9.3-p392.
In one of my controllers The "create" action can receive an image (as a ActionDispatch::Http::UploadedFile)
I'm trying to monkeypatch ActionDispatch::Http::UploadedFile by overriding its as_json method to return the tempfile path instead of the tempfile File object itself.
The reason why I'm doing this is because I have a database logger that serializes the log context (which includes the request params) by calling to_json on the context.
Problem is that calling to_json on said class produces a ton of binary data which fill up my log.
So I have created the following directory structure under "lib":
"action_dispatch/http/uploaded_file.rb"
Inside this file the class is named ActionDispatch::Http::UploadedFile
I've also added the lib folder to application.rb by:
config.autoload_paths += Dir["#{config.root}/lib"]
Problem is that rails doesn't load my monkey-patched class.
If I add require "action_dispatch/http/uploaded_file"to the top of my controller file everything works fine.
Why doesn't Rails autoloads my monkey-patched class?
The directory structure and class naming is according to the Rails conventions.
Move your code to config/initializers/your_filename.rb file. The code in these files is loaded during Rails Application boot process.
That's in general. But I'm not sure why you want to monkey-patch ActionDispatch::Http::UploadedFile class, because I haven't got much info about your app.
try
config.autoload_paths += ["#{config.root}/lib"]
I place a file name g.rb in side Rails.root/lib folder
The file content is like this:
module Google
end
Then I add
config.autoload_paths += %W(#{config.root}/lib #{Rails.root}/app/delayed_jobs)
to my Rails.root/config/application.rb
However, when I try to invoke Google from rails console, an exception is thrown. The exception goes away only if I execute require 'google'.
Why? Shouldn't my file is autoloaded and shouldn't I access the module without any extra require statement?
Hmm, I discovered an interesting thing. In order for Rails to auto load my class, the class name should be compliant to the file name and the folder structure.
For example, if I want to have Google module autoloaded, I must placed it inside google.rb, directly under /lib (incase I specify autoload from /lib).
If I want to auto load Google::Docs, then I either place it inside google.rb or google/docs.rb
I had a similar problem with getting my module to run on Heroku. In addition to the autoload naming convention stated by Stephen C, I found out that the module code must be require'd due to a threadsafe assumption made by the Rails' production environment on Heroku (even though threadsafe was commented out in my production.rb configuration file.) As soon as I require'd the module file before calling include on the module, everything started to work.
require 'mymodule'
include Mymodule
Please take a look at this excellent article on the subject of getting Modules to load correctly in Heroku (production).
That's because the point of autoload is not to 'require' everything up front (startup penalty). Classes are loaded as they are needed/referenced. In order to do this, you need some way to know where to look for the class. Otherwise, you would have to load every file in the autoload directory in advance to see what classes are declared. It's a tradeoff, but requiring everything in advance (as marbaq suggests) is not autoloading.
You can use the autoload command as provided by Ruby, which takes two arguments, the module to load (symbolized, i.e. :Google in your case), and the second argument is the filename, which would be g.rb if lib is in your load path ($:). See the Ruby docs for autoload.
Change config.autoload_paths to config.eager_load_paths
(based on Rails issue #6850 and Force reload! from lib directory in rails 3.2 console)
I faced the same problem just now, and my "solution" (or rather workaround) was to manually require every needed file from Rails.root/lib in my application.rb.
require 'lib/message'
require 'lib/store'
require 'lib/vault/vault.rb'
require 'lib/custom_loggers'
module MyApplication
class Application < Rails::Application
My next step would be to categorize the files in module folders as you mention.
i found this solution recently
config/application.rb
module AppName
class Application < Rails::Application
# Custom directories with classes and modules you want to be autoloadable.
config.autoload_paths += Dir[Rails.root.join('app', 'models', '{**}')]
config.autoload_paths += Dir[Rails.root.join('app', 'lib', 'extensions')]
end
end
the first config call induces rails to auto-load all sub-directories of the app/models directory
so now i can have /app/models/sub_directory/model.rb auto-loaded
(handy for organising an app with a large code base)
the second config call induces rails to autoload the lib/extensions directory
hope this helps
note: i believe this is rails 3 specific