Including nested objects in a JSON response, from MongoMapper objects

Question

class Api::StoresController < ApplicationController respond_to :json def index @stores = Store.all(:include => :products) respond_with @stores end end 

Returns only stores without their products, as well as

 Store.find(:all).to_json(:include => :products) 

The association is being tested, I see nested products in the console, for example,

 Store.first.products 

What is the right way to get their products included in MongoMapper?

Here are my models:

  class Store include MongoMapper::Document many :products, :foreign_key => :store_ids end class Product include MongoMapper::Document key :store_ids, Array, :typecast => 'ObjectId' many :stores, :in => :store_ids end 

UPDATE

When I tried Scott's suggestion, I added the following to the Store model:

 def self.all_including_nested stores = [] Store.all.each do |store| stores << store.to_hash end end def to_hash keys = self.key_names hash = {} keys.each{|k| hash[k] = self[k]} hash[:products] = self.products hash[:services] = self.services hash end 

And in the controller:

 def index @stores = Store.all_including_nested respond_with @stores end 

Which looks like it should work? Assuming the hash array will be called #to_json, and then the same thing will happen with every hash and each Product + Service. I read through the ActiveSupport :: JSON source, and so far this is what I suffered from it.

But, while not working ... :(

Answer 1

Take a look at the as_json() method. You put this in your models, define your json, and then just call the render :json method and get what you want.

 class Something def as_json(options={}) {:account_name => self.account_name, :expires_on => self.expires_on.to_s, :collections => self.collections, :type => "Institution"} end end 

You will notice self.collections , which represents a lot of relationships. This model also has as_json() :

 class Collection def as_json(options={}) {:name => self.name, :title => self.title, :isbn => self.isbn, :publisher => self.publisher, :monthly_views => self.monthly_views} end end 

This one contains self.monthly_views , which represents a different relationship.

Then in your controller:

 @somethings = Something.all render :json => @somethings 

Answer 2

You may need to create your own method to generate a hash, and then turn the hash into JSON. I think something like this:

 store = Store.first keys = store.key_names hash = {} keys.each{|k| hash[k] = store[k]} hash[:products] = store.products hash.to_json