Listing the names of associated models

Question

class Article < ActiveRecord::Base
  has_many :comments
  belongs_to :category
end

Is there a class method for Article with which I can retrieve a list of associations? I know by looking at the model's code that Article is associated to Comment and Category. But is there a method to get these associations programmatically?

possible duplicate of [Relationships of model](http://stackoverflow.com/questions/3178587/relationships-of-model) — fl00r, Apr 20 '11 at 15:50

Mike Lewis · Accepted Answer · 2011-04-20T17:32:32.287

78

You want ActiveRecord::Reflection::ClassMethods#reflect_on_all_associations

So it would be:

 Article.reflect_on_all_associations

And you can pass in an optional parameter to narrow the search down, so:

 Article.reflect_on_all_associations(:has_many)

 Article.reflect_on_all_associations(:belongs_to)

Keep in mind that if you want the list of all the names of the models you can do something like:

Article.reflect_on_all_associations(:belongs_to).map(&:name)

This will return a list of all the model names that belong to Article.

edited Apr 20 '11 at 17:32

answered Apr 20 '11 at 15:50

Mike Lewis

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This is not totally accurate. That returns the name of the associations, not the name of the models. – zach Nov 20 '15 at 04:13
Names of models are very similar: `Article.reflect_on_all_associations(:belongs_to).map(&:class_name)` – Bad Request Feb 26 '20 at 23:54
how you get the names that are associated via `has_rich_text` and `has_many_attached`? – konyak Aug 28 '20 at 18:35
I have simply been using `reflections` with `keys` as needed. – Pysis Sep 29 '20 at 19:09

Listing the names of associated models

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