Advanced rest interface tips

All the tutorials I see on doing a rest interface with rails only show
how to do it with resources 1 level deep, i.e., they don’t show a good
way to go about doing a rest interface for nested type rest
interfaces. For example:

If I was doing this with rails would I have to use 2 different
controllers: users_controller & companies_controller?

Are there any good guides for this?


Probably, and you can use nested routes like this:

map.resources :users do |users|
users.resources :companies


Yes, I would use two controllers. The users_controller would look like
a normal RESTful controller.
The companies_controller requires a little more work.
I tend to do most of it with before_filters

class CompaniesController < ApplicationController

before_filter :find_user
before_filter :find_companies, :only => :index
before_filter :find_company, :only => [:show,:update,:edit,:destroy]


def find_user
@user = User.find_by_id(params[:user_id])

def find_companies
@companies = @user.companies

def find_company
@company = @user.companies.find_by_id(params[:id])


def index

For the new/create actions, you should use:
@company =[:company])

Which makes the new company belong to the @user and (I think) updates
any counter cache you might be using.
Your company_path now takes two arguements, @user and @company; the
companies_path takes @user.

Those methods are the bare minimum, and in a real application, I would
probably have something to redirect to a 404 if a user or company
wasn’t found.

In your routes, you will need a declaration as aurélien said.

Depending on the nature of the application, you might want to
substitute the @user in the build statement for something representing
the currently logged in user. Something similar could be done in a
filter method so that the searches for the update, edit, destroy
actions only find companies belonging to the current user.

Hope this helps,