Add `GET /api/v2_alpha/notifications/:group_key/accounts` (#31725)

app/controllers/api/v2_alpha/notifications/accounts_controller.rb

@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+class Api::V2Alpha::Notifications::AccountsController < Api::BaseController
+  before_action -> { doorkeeper_authorize! :read, :'read:notifications' }
+  before_action :require_user!
+  before_action :set_notifications!
+  after_action :insert_pagination_headers, only: :index
+
+  def index
+    @accounts = load_accounts
+    render json: @accounts, each_serializer: REST::AccountSerializer
+  end
+
+  private
+
+  def load_accounts
+    @paginated_notifications.map(&:from_account)
+  end
+
+  def set_notifications!
+    @paginated_notifications = begin
+      current_account
+        .notifications
+        .without_suspended
+        .where(group_key: params[:notification_group_key])
+        .includes(from_account: [:account_stat, :user])
+        .paginate_by_max_id(
+          limit_param(DEFAULT_ACCOUNTS_LIMIT),
+          params[:max_id],
+          params[:since_id]
+        )
+    end
+  end
+
+  def next_path
+    api_v2_alpha_notification_accounts_url pagination_params(max_id: pagination_max_id) if records_continue?
+  end
+
+  def prev_path
+    api_v2_alpha_notification_accounts_url pagination_params(min_id: pagination_since_id) unless @paginated_notifications.empty?
+  end
+
+  def pagination_collection
+    @paginated_notifications
+  end
+
+  def records_continue?
+    @paginated_notifications.size == limit_param(DEFAULT_ACCOUNTS_LIMIT)
+  end
+end

app/controllers/api/v2_alpha/notifications_controller.rb

@@ -46,7 +46,7 @@ class Api::V2Alpha::NotificationsController < Api::BaseController
   end
 
   def show
-    @notification = current_account.notifications.without_suspended.find_by!(group_key: params[:id])
+    @notification = current_account.notifications.without_suspended.find_by!(group_key: params[:group_key])
     presenter = GroupedNotificationsPresenter.new(NotificationGroup.from_notifications([@notification]))
     render json: presenter, serializer: REST::DedupNotificationGroupSerializer
   end
@@ -57,7 +57,7 @@ class Api::V2Alpha::NotificationsController < Api::BaseController
   end
 
   def dismiss
-    current_account.notifications.where(group_key: params[:id]).destroy_all
+    current_account.notifications.where(group_key: params[:group_key]).destroy_all
     render_empty
   end
 

config/routes/api.rb

@@ -344,7 +344,7 @@ namespace :api, format: false do
   end
 
   namespace :v2_alpha do
-    resources :notifications, only: [:index, :show] do
+    resources :notifications, param: :group_key, only: [:index, :show] do
       collection do
         post :clear
         get :unread_count
@@ -353,6 +353,8 @@ namespace :api, format: false do
       member do
         post :dismiss
       end
+
+      resources :accounts, only: [:index], module: :notifications
     end
   end
 

spec/requests/api/v2_alpha/notifications/accounts_spec.rb

@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe 'Accounts in grouped notifications' do
+  let(:user)    { Fabricate(:user, account_attributes: { username: 'alice' }) }
+  let(:token)   { Fabricate(:accessible_access_token, resource_owner_id: user.id, scopes: scopes) }
+  let(:scopes)  { 'read:notifications write:notifications' }
+  let(:headers) { { 'Authorization' => "Bearer #{token.token}" } }
+
+  describe 'GET /api/v2_alpha/notifications/:group_key/accounts', :inline_jobs do
+    subject do
+      get "/api/v2_alpha/notifications/#{user.account.notifications.first.group_key}/accounts", headers: headers, params: params
+    end
+
+    let(:params) { {} }
+
+    before do
+      first_status = PostStatusService.new.call(user.account, text: 'Test')
+      FavouriteService.new.call(Fabricate(:account), first_status)
+      FavouriteService.new.call(Fabricate(:account), first_status)
+      ReblogService.new.call(Fabricate(:account), first_status)
+      FollowService.new.call(Fabricate(:account), user.account)
+      FavouriteService.new.call(Fabricate(:account), first_status)
+    end
+
+    it_behaves_like 'forbidden for wrong scope', 'write write:notifications'
+
+    it 'returns a list of accounts' do
+      subject
+
+      expect(response).to have_http_status(200)
+
+      # The group we are interested in is only favorites
+      notifications = user.account.notifications.where(type: 'favourite').reorder(id: :desc)
+      expect(body_as_json).to match(
+        [
+          a_hash_including(
+            id: notifications.first.from_account_id.to_s
+          ),
+          a_hash_including(
+            id: notifications.second.from_account_id.to_s
+          ),
+          a_hash_including(
+            id: notifications.third.from_account_id.to_s
+          ),
+        ]
+      )
+    end
+
+    context 'with limit param' do
+      let(:params) { { limit: 2 } }
+
+      it 'returns the requested number of accounts, with pagination headers' do
+        subject
+
+        expect(response).to have_http_status(200)
+
+        # The group we are interested in is only favorites
+        notifications = user.account.notifications.where(type: 'favourite').reorder(id: :desc)
+        expect(body_as_json).to match(
+          [
+            a_hash_including(
+              id: notifications.first.from_account_id.to_s
+            ),
+            a_hash_including(
+              id: notifications.second.from_account_id.to_s
+            ),
+          ]
+        )
+
+        expect(response)
+          .to include_pagination_headers(
+            prev: api_v2_alpha_notification_accounts_url(limit: params[:limit], min_id: notifications.first.id),
+            next: api_v2_alpha_notification_accounts_url(limit: params[:limit], max_id: notifications.second.id)
+          )
+      end
+    end
+  end
+end