find_by_param helps you dealing with permalinks and finding objects by our permalink value
class Post < ActiveRecord:Base make_permalink :with => :title end
now you can do
If you have a permalink-column find_by_param saves the permalink there and uses that otherwise it just uses the provided attribute.
% gem install find_by_param
Building your own
% gem build find_by_param.gemspec % gem install find_by_param-VERSION.gem
As Rails plugin
% script/plugin install git://github.com/bumi/find_by_param.git
find_by_param is known to work with Rails 2.3, 3.0 and 3.1.
make_permalink :with => :login make_permalink :with => :title, :prepend_id => true make_permalink :with => :name, :forbidden => %w(new edit)
Post.create(:title => "hey ho let's go!").to_param #=> "hey-ho-lets-go" # ... to_param is the method Rails calls to create the URL values Post.find_by_param("hey-ho-lets-go") #=> <Post> Post.find_by_param("is-not-there") #=> nil Post.find_by_param!("is-not-there") #=> raises ActiveRecord::RecordNotFound
Options for make_permalink
The following options may be used, when configuring the permalink generation with make_permalink.
The attribute that should be used as permalink
The name of your permalink column. make_permalink first checks if there is a column.
:prepend_id => [true|false]
Do you want to prepend the ID to the permalink? for URLs like: posts/123-my-post-title - find_by_param uses the ID column to search.
:param_size => [Number]
Desired maximum size of the permalink, default is 50.
:escape => [true|false]
Do you want to escape the permalink value? (strip chars like öä?&) - actually you must do that
:forbidden => [Regexp|String|Array of Strings]
Define which values should be forbidden. This is useful when combining user defined values to generate permalinks in combination with restful routing. Make sure, especially in the case of a Regexp argument, that values may become valid by adding or incrementing a trailing integer.
Class methods provided by find_by_param
The following methods are added as public methods to all classes containing a permalink field.
Look up a value by its permalink value, returns matching instance or nil, if none is found.
Look up a value by its permalink value, returns matching instance or raises ActiveRecord::RecordNotFound, if none is found.
Alex Sharp (github.com/ajsharp) pointed to an issue with STI. Better call make_permalink in every child class and not only in the parent class..
write nice docs
write nicer tests
Copyright © 2007 [Michael Bumann - Railslove.com], released under the MIT license