- Inheritance
Polymorphic URL helpers are methods for smart resolution to a named route call when given an Active Record model instance. They are to be used in combination with ActionController::Resources.
These methods are useful when you want to generate correct URL or path to a RESTful resource without having to know the exact type of the record in question.
Nested resources and/or namespaces are also supported, as illustrated in the example:
polymorphic_url([:admin, @article, @comment])
results in:
admin_article_comment_url(@article, @comment)
Usage within the framework
Polymorphic URL helpers are used in a number of places throughout the Rails framework:
- url_for, so you can use it with a record as the argument, e.g. url_for(@article);
- ActionView::Helpers::FormHelper uses polymorphic_path, so you can write form_for(@article) without having to specify :url parameter for the form action;
- redirect_to (which, in fact, uses url_for) so you can write redirect_to(post) in your controllers;
- ActionView::Helpers::AtomFeedHelper, so you don‘t have to explicitly specify URLs for feed entries.
Prefixed polymorphic helpers
In addition to polymorphic_url and polymorphic_path methods, a number of prefixed helpers are available as a shorthand to :action => "…" in options. Those are:
- edit_polymorphic_url, edit_polymorphic_path
- new_polymorphic_url, new_polymorphic_path
Example usage:
edit_polymorphic_path(@post) # => "/posts/1/edit" polymorphic_path(@post, :format => :pdf) # => "/posts/1.pdf"
Methods
Instance
| Visibility | Signature |
|---|---|
| public | formatted_polymorphic_path (record_or_hash, options = {}) |
| public | formatted_polymorphic_url (record_or_hash, options = {}) |
| public | polymorphic_path (record_or_hash_or_array, options = {}) |
| public | polymorphic_url (record_or_hash_or_array, options = {}) |
Instance Method Detail
formatted_polymorphic_path(record_or_hash, options = {})
formatted_polymorphic_url(record_or_hash, options = {})
polymorphic_path(record_or_hash_or_array, options = {})
Returns the path component of a URL for the given record. It uses polymorphic_url with :routing_type => :path.
polymorphic_url(record_or_hash_or_array, options = {})
Constructs a call to a named RESTful route for the given record and returns the resulting URL string. For example:
# calls post_url(post) polymorphic_url(post) # => "http://example.com/posts/1" polymorphic_url([blog, post]) # => "http://example.com/blogs/1/posts/1" polymorphic_url([:admin, blog, post]) # => "http://example.com/admin/blogs/1/posts/1" polymorphic_url([user, :blog, post]) # => "http://example.com/users/1/blog/posts/1"
Options
- :action - Specifies the action prefix for the named route: :new or :edit. Default is no prefix.
- :routing_type - Allowed values are :path or :url. Default is :url.
Examples
# an Article record polymorphic_url(record) # same as article_url(record) # a Comment record polymorphic_url(record) # same as comment_url(record) # it recognizes new records and maps to the collection record = Comment.new polymorphic_url(record) # same as comments_url()