Where to put `r` alias for method `render` in Rails? - ruby-on-rails

I my views I want to use r alias for method render.
Following code will do this stuff:
module ActionView
# Make alias for :render method
class Base
alias_method :r, :render
end
end
This it pretty handy and nice for me, however I want to ask, what is the best place for this particular snippet? Currently I put this to my app/helpers/application_helper.rb.

Related

Rails undefined method for Module

In Rails, how do you use a specific method from a module. For eg,
# ./app/controllers/my_controller.rb
class MyController < ApplicationController
include MyModule
def action
MyModule.a_method
end
private
def a_method
...
end
end
# ------------------------------------------------ #
# ./app/helpers/my_module.rb
module MyModule
def a_method
...
end
end
MyController includes MyModule. And in action ,I want to use MyModule.a_method (Please note I also have a private a_method in MyController and I don't want to use this.)
Things I've tried :
1) Defining the method in the module as self.
def self.a_method
end
2) Using the :: notation in controller (MyModule::a_method)
The error that I keep getting is
Undefined method:a_method for MyModule:module
For now, I've resorted to using a different name for the modules method. But I'd like to know how to namespace the function with either the Module:: or Module. notation
[UPDATE - 11/24/2014]
adding file structure in code, since Rails heavily relies on convention.
So I am not really sure what you are trying to accomplish with your module but a quick solution to get it working is below.
Move my_module.rb out of helpers and into lib/my_module.rb. The helpers directory is for methods that you use in your views. The convention is to utilize helpers that are namespaced after their respective controller or the application_helper.rb for global methods for your views. Not sure if that's what you are trying to accomplish with your module but wanted to throw that out there.
Create an initializer (you can all it whatever) in config/initializers/custom_modules.rb and add require 'my_module'
Update the a_method back to be self.a_method
You can now call MyModule.a_method in your app
Don't forget to restart your server for changes to lib/my_module.rb to take effect.
Also, a lot of people reference this post by Yehuda Katz as guidance on where to store code for your app. Thought it might be a helpful reference.
if you include MyModule into MyController, all the "instance methods" of the first will be mixed-in into the 2nd.
So if you only want to call MyModule.a_method, no need to include your module.
Then you'd want to require (or better autoload) your module before using it. To do so place it in controllers/concerns/my_module.rb, rails (4 at least) should autoload it, otherwise require its file in an intializer
# my_module.rb
module MyModule
def self.a_method
...
end
end
should work, but doing
# my_module.rb
module MyModule
extend self
def a_method
...
end
end
is more clean to me. You'd like to have a look to rails active support concern to understand the "rails way" on this topic.

Monkey patching Rails

I need to monkey-patch one of the Rails core classes, specifically ActionView::Helpers::UrlHelper::ClassMethods.link_to method. As far as I remember there are some events fired when parts of Rails are loaded, how to add handlers for them? Or should I just put the code into initializer?
link_to does not appear to be in ClassMethods. From here.
In config/initializers/url_helper_extensions.rb
module ActionView
module Helpers
module UrlHelper
alias_method :_link_to, :link_to
def link_to
# Your code ...
# Call original method if you want.
_link_to
end
end
end
end

Trying to import my helpers into a custom lib/class and suddenly I need a config?

Real simple.
class Template
def stuff_i_want
stylesheet_link_tag('my_stylesheet')
end
class << self
include ActionView::Helpers::TagHelper
include ActionView::Helpers::AssetTagHelper
end
end
And this returns..
undefined local variable or method `config' for Template:Class
from /Users/elephanttrip/.rvm/gems/ruby-1.9.3-p385#shasta/gems/actionpack-3.1.12/lib/action_view/helpers/asset_tag_helpers/stylesheet_tag_helpers.rb:137:in `stylesheet_link_tag'
From the stylesheet_tag_helpers.rb in Railtie :
def stylesheet_link_tag(*sources)
#stylesheet_include ||= StylesheetIncludeTag.new(config, asset_paths)
#stylesheet_include.include_tag(*sources)
end
Config isn't instantiated in that file anywhere, so I'm assuming its' required from somewhere else.. I have no idea where, or how.
Anyone know how to inject/pass a config into my helper? I've never needed to do this before.
It looks like you're actually including your helpers into Object - and then defining your Template class. I've no idea why it's asking for config, but try putting the includes inside your class definition and see if the problem goes away.
You probably shouldn't be randomly including helpers into things over than your views though - that's not what they're for.
Why not use view_context instead.
So instead of including the helper modules you can do this:
class Template
def stuff_i_want
view_context.stylesheet_link_tag('my_stylesheet')
end
end
This should work fine.
And if you want to include you helpers then use the below code:
class Template
include ActionView::Helpers::TagHelper
include ActionView::Helpers::AssetTagHelper
def stuff_i_want
stylesheet_link_tag('my_stylesheet')
end
end
Ideally you should not include helpers in ur controllers as they are not intended for that.
Hope that helps

Multiple Rails Helpers w/ Same Method Name

I have two different helper files (photos_helper & comments_helper) w/ that have a method named actions_for. How can I explicitly call which helper method that I need? I know that I could just rename one of them but I would prefer to keep them the same. I tried PhotosHelper::actions_for but that doesn't seem to work.
In Rails 3 all helpers are always (in Rails 3.1 a patch exists to selectively allow helpers again) included. What's happening behind the scenes:
class YourView
include ApplicationHelper
include UserHelper
include ProjectHelper
...
end
So depending on the order Rails includes them, any of your actions_for methods will be used. There is no way you can explicitly chose one of them.
If you would have to explicitly call ProjectHelper.action_for, you could also name your methods project_action_for - simplest solution.
Make both of them a Class Method
module LoginsHelper
def self.your_method_name
"LoginsHelper"
end
end
AND
module UsersHelper
def self.your_method_name
"UsersHelper"
end
end
Then in View
LoginsHelper.your_method_name #Gives 'LoginsHelper'
AND
UsersHelper.your_method_name #Gives 'UsersHelper'

Rails: How to override stylesheet_path

I've been trying to override Rails' stylesheet_path helper, but I haven't found a way how. I can't just open the ActionView::Helpers::AssetTagHelper module and override it there, because Rails won't pick up my new method.
I know it's probably because the module gets mixed in, so how do I get around that?
Are you doing this so that stylesheet_link_tag will result in something different from normal? If so, just override that in a helper :)
Alternatively, if you really want to override stylesheet_path, you need to also redefine the alias, as, curiously, it's only accessed via its alias (in Rails 2.3.2). For example, I put this in environment.rb and it worked:
module ActionView
module Helpers
module AssetTagHelper
def stylesheet_path(source)
"x"
end
alias_method :path_to_stylesheet, :stylesheet_path
end
end
end
I personally wouldn't go this route but it should work for you if you need it :)

Resources