Ruby-on-rails – How to manage CSS Stylesheet Assets in Rails 3.1

ruby-on-railsruby-on-rails-3.1sasssprockets

I'm just learning the new asset pipeline in Rails 3.1. One particular problem I'm having is with the way Sprockets just mashes all the found CSS stylesheets into one massive stylesheet. I understand why this is advantageous over manually merging stylesheets and minifying for production. But I want to be able to selectively cascade stylesheets instead of having all rules all mashed together. For instance, I want:

master.css

to be loaded by all pages in the Rails app, but I want

admin.css only to be loaded by pages/views within the admin section/namespace.

How can I take advantage of the great way that Rails 3.1 combines stylesheets and minifies them for production, but also have the former flexibility of being able to load only certain stylesheet combinations per layout?

Or should this be done by adding a class to body tags in layouts-

body class="admin"

And then target style rules as appropriate. Using SASS scoped selectors this might be a reasonable solution.

Best Answer

This is how i solved the styling issue: (excuse the Haml)

%div{:id => "#{params[:controller].parameterize} #{params[:view]}"}
    = yield

This way i start all the page specific .css.sass files with:

#post
  /* Controller specific code here */
  &#index
    /* View specific code here */
  &#new
  &#edit
  &#show

This way you can easily avoid any clashes.

Hope this helped some.

Related Solutions

Ruby-on-rails – Rails: How to rename a database column in a Ruby on Rails migration

rename_column :table, :old_column, :new_column

You'll probably want to create a separate migration to do this. (Rename FixColumnName as you will.):

script/generate migration FixColumnName
# creates  db/migrate/xxxxxxxxxx_fix_column_name.rb

Then edit the migration to do your will:

# db/migrate/xxxxxxxxxx_fix_column_name.rb
class FixColumnName < ActiveRecord::Migration
  def self.up
    rename_column :table_name, :old_column, :new_column
  end

  def self.down
    # rename back if you need or do something else or do nothing
  end
end

For Rails 3.1 use:

While, the up and down methods still apply, Rails 3.1 receives a change method that "knows how to migrate your database and reverse it when the migration is rolled back without the need to write a separate down method".

See "Active Record Migrations" for more information.

rails g migration FixColumnName

class FixColumnName < ActiveRecord::Migration
  def change
    rename_column :table_name, :old_column, :new_column
  end
end

If you happen to have a whole bunch of columns to rename, or something that would have required repeating the table name over and over again:

rename_column :table_name, :old_column1, :new_column1
rename_column :table_name, :old_column2, :new_column2
...

You could use change_table to keep things a little neater:

class FixColumnNames < ActiveRecord::Migration
  def change
    change_table :table_name do |t|
      t.rename :old_column1, :new_column1
      t.rename :old_column2, :new_column2
      ...
    end
  end
end

Then just db:migrate as usual or however you go about your business.

For Rails 4:

While creating a Migration for renaming a column, Rails 4 generates a change method instead of up and down as mentioned in the above section. The generated change method is:

$ > rails g migration ChangeColumnName

which will create a migration file similar to:

class ChangeColumnName < ActiveRecord::Migration
  def change
    rename_column :table_name, :old_column, :new_column
  end
end

Ruby-on-rails – How to get the current absolute URL in Ruby on Rails

For Rails 3.2 or Rails 4+

You should use request.original_url to get the current URL. Source code on current repo found here.

This method is documented at original_url method, but if you're curious, the implementation is:

def original_url
  base_url + original_fullpath
end

For Rails 3:

You can write "#{request.protocol}#{request.host_with_port}#{request.fullpath}", since request.url is now deprecated.

For Rails 2:

You can write request.url instead of request.request_uri. This combines the protocol (usually http://) with the host, and request_uri to give you the full address.