Adding OAuth access scopes, fixing OAuth authorization UI, adding rate limiting

to the API

app/controllers/api/v1/accounts_controller.rb

@@ -1,5 +1,7 @@
 class Api::V1::AccountsController < ApiController
-  before_action :doorkeeper_authorize!
+  before_action -> { doorkeeper_authorize! :read }, except: [:follow, :unfollow, :block, :unblock]
+  before_action -> { doorkeeper_authorize! :follow }, only: [:follow, :unfollow, :block, :unblock]
+
   before_action :set_account, except: [:verify_credentials, :suggestions]
   respond_to    :json
 

app/controllers/api/v1/follows_controller.rb

@@ -1,5 +1,5 @@
 class Api::V1::FollowsController < ApiController
-  before_action :doorkeeper_authorize!
+  before_action -> { doorkeeper_authorize! :follow }
   respond_to    :json
 
   def create

app/controllers/api/v1/media_controller.rb

@@ -1,5 +1,5 @@
 class Api::V1::MediaController < ApiController
-  before_action :doorkeeper_authorize!
+  before_action -> { doorkeeper_authorize! :write }
   respond_to    :json
 
   def create

app/controllers/api/v1/statuses_controller.rb

@@ -1,5 +1,7 @@
 class Api::V1::StatusesController < ApiController
-  before_action :doorkeeper_authorize!
+  before_action -> { doorkeeper_authorize! :read }, except: [:create, :destroy, :reblog, :unreblog, :favourite, :unfavourite]
+  before_action -> { doorkeeper_authorize! :write }, only:  [:create, :destroy, :reblog, :unreblog, :favourite, :unfavourite]
+
   respond_to    :json
 
   def show

app/controllers/api_controller.rb

@@ -1,7 +1,10 @@
 class ApiController < ApplicationController
   protect_from_forgery with: :null_session
+
   skip_before_action :verify_authenticity_token
 
+  before_action :set_rate_limit_headers
+
   rescue_from ActiveRecord::RecordInvalid do |e|
     render json: { error: e.to_s }, status: 422
   end
@@ -22,8 +25,27 @@ class ApiController < ApplicationController
     render json: { error: 'Remote SSL certificate could not be verified' }, status: 503
   end
 
+  def doorkeeper_unauthorized_render_options(*)
+    { json: { error: 'Not authorized' } }
+  end
+
+  def doorkeeper_forbidden_render_options(*)
+    { json: { error: 'This action is outside the authorized scopes' } }
+  end
+
   protected
 
+  def set_rate_limit_headers
+    return if request.env['rack.attack.throttle_data'].nil?
+
+    now        = Time.now.utc
+    match_data = request.env['rack.attack.throttle_data']['api']
+
+    response.headers['X-RateLimit-Limit']     = match_data[:limit].to_s
+    response.headers['X-RateLimit-Remaining'] = (match_data[:limit] - match_data[:count]).to_s
+    response.headers['X-RateLimit-Reset']     = (now + (match_data[:period] - now.to_i % match_data[:period])).to_s
+  end
+
   def current_resource_owner
     User.find(doorkeeper_token.resource_owner_id) if doorkeeper_token
   end

app/controllers/home_controller.rb

@@ -15,6 +15,6 @@ class HomeController < ApplicationController
   end
 
   def find_or_create_access_token
-    Doorkeeper::AccessToken.find_or_create_for(Doorkeeper::Application.where(superapp: true).first, current_user.id, nil, Doorkeeper.configuration.access_token_expires_in, Doorkeeper.configuration.refresh_token_enabled?)
+    Doorkeeper::AccessToken.find_or_create_for(Doorkeeper::Application.where(superapp: true).first, current_user.id, 'read write follow', Doorkeeper.configuration.access_token_expires_in, Doorkeeper.configuration.refresh_token_enabled?)
   end
 end

app/controllers/oauth/authorizations_controller.rb

@@ -0,0 +1,9 @@
+class Oauth::AuthorizationsController < Doorkeeper::AuthorizationsController
+  before_action :store_current_location
+
+  private
+
+  def store_current_location
+    store_location_for(:user, request.url)
+  end
+end