controllers.md

Models on GTHC

What is a controller and the MVC architecture?

When to create a controller?

Typically there won't be a need for a new controller, unless a new model has been created. Otherwise, using the controllers that already exist should be sufficient.

How to use a controller?

In our use case, controllers are necessary for handling all of our API routes, and what happens whenever certain HTTP requests hit a certain endpoint. This is all assigned in the routes.rb file which will direct any endpoint to a controller and function/method within the controller.

Custom Endpoint/Single Resource Routing

For example, if you want to understand how the hour breakdown data is collected from the API (it is the GET request on url, api/v1/team/hours), check routes.rb at line 52:

namespace :api do
  namespace :v1 do
    ...
    # team
    get 'team/hours', to: 'teams#team_hours'
    ...
  end
end

This is an example of how a GET request can be directed to a specific controller and function. The statement get 'team/hours' means grab any GET request at the url <url>/team/hours, and since the request is under the namespace of api/v1, the full url is <url>/api/v1/team/hours. The rest of the line, to: 'teams#team_hours', is just the part that directs the request to a controller and function in the controller. teams is referring to the controller of the Team model, which would be found at controllers/api/v1/teams_controller.rb (make note of the namespace taking importance in the file location as well). #team_hours is just rails' way of identifying the function of where to run this GET request. So, if you go to the mentioned controller (at ./controllers/api/v1/team_controller.rb), and find the function inside of the file named team_hours, you will find what exactly is running when an HTTP request of the method GET is called.

Resource Routing

While looking at routes.rb, you may have also noticed that some of the routes are declared using the resources function. For example,

namespace :api do
    namespace :v1 do
      resources :shifts, :teams, :captains, :users
      ...
    end
end

This is a function that rails provides that pre-generates signle resource routes for you. In the example above, the models Shift, Team, Captain, and User are all getting pre-generated routes, which make building APIs much easier as the pre-generated routes are the most common used endpoints needed for any model.

For more extensive detail on what and how to use a resource route on rails or anything related to routing and controllers on Rails, check their official documentation here.