Fix pagination for resource events

Remove pagination logic from ResourceLabelEventFinder.

Remove ResourceLabelEventFinder and update specs

app/finders/resource_label_event_finder.rb

-# frozen_string_literal: true
-
-class ResourceLabelEventFinder
-  include FinderMethods
-
-  MAX_PER_PAGE = 100
-
-  attr_reader :params, :current_user, :eventable
-
-  def initialize(current_user, eventable, params = {})
-    @current_user = current_user
-    @eventable = eventable
-    @params = params
-  end
-
-  def execute
-    events = eventable.resource_label_events.inc_relations
-    events = events.page(page).per(per_page)
-    events = visible_to_user(events)
-
-    Kaminari.paginate_array(events)
-  end
-
-  private
-
-  def visible_to_user(events)
-    ResourceLabelEvent.preload_label_subjects(events)
-
-    events.select do |event|
-      Ability.allowed?(current_user, :read_label, event)
-    end
-  end
-
-  def per_page
-    [params[:per_page], MAX_PER_PAGE].compact.min
-  end
-
-  def page
-    params[:page] || 1
-  end
-end

app/models/resource_label_event.rb

@@ -71,6 +71,14 @@ class ResourceLabelEvent < ResourceEvent
     end
   end
 
+  def self.visible_to_user?(user, events)
+    ResourceLabelEvent.preload_label_subjects(events)
+
+    events.select do |event|
+      Ability.allowed?(user, :read_label, event)
+    end
+  end
+
   private
 
   def label_reference

changelogs/unreleased/220192-fix-pagination-pd.yml

+---
+title: Fix pagination for resource label events
+merge_request: 33821
+author:
+type: fixed

lib/api/resource_label_events.rb

@@ -27,10 +27,9 @@ module API
         get ":id/#{eventables_str}/:eventable_id/resource_label_events" do
           eventable = find_noteable(eventable_type, params[:eventable_id])
 
-          opts = { page: params[:page], per_page: params[:per_page] }
-          events = ResourceLabelEventFinder.new(current_user, eventable, opts).execute
+          events = eventable.resource_label_events.inc_relations
 
-          present paginate(events), with: Entities::ResourceLabelEvent
+          present ResourceLabelEvent.visible_to_user?(current_user, paginate(events)), with: Entities::ResourceLabelEvent
         end
 
         desc "Get a single #{eventable_type.to_s.downcase} resource label event" do

spec/finders/resource_label_event_finder_spec.rb

-# frozen_string_literal: true
-
-require 'spec_helper'
-
-describe ResourceLabelEventFinder do
-  let_it_be(:user) { create(:user) }
-  let_it_be(:issue_project) { create(:project) }
-  let_it_be(:issue) { create(:issue, project: issue_project) }
-
-  describe '#execute' do
-    subject { described_class.new(user, issue).execute }
-
-    it 'returns events with labels accessible by user' do
-      label = create(:label, project: issue_project)
-      event = create_event(label)
-      issue_project.add_guest(user)
-
-      expect(subject).to eq [event]
-    end
-
-    it 'filters events with public project labels if issues and MRs are private' do
-      project = create(:project, :public, :issues_private, :merge_requests_private)
-      label = create(:label, project: project)
-      create_event(label)
-
-      expect(subject).to be_empty
-    end
-
-    it 'filters events with project labels not accessible by user' do
-      project = create(:project, :private)
-      label = create(:label, project: project)
-      create_event(label)
-
-      expect(subject).to be_empty
-    end
-
-    it 'filters events with group labels not accessible by user' do
-      group = create(:group, :private)
-      label = create(:group_label, group: group)
-      create_event(label)
-
-      expect(subject).to be_empty
-    end
-
-    it 'paginates results' do
-      label = create(:label, project: issue_project)
-      create_event(label)
-      create_event(label)
-      issue_project.add_guest(user)
-
-      paginated = described_class.new(user, issue, per_page: 1).execute
-
-      expect(subject.count).to eq 2
-      expect(paginated.count).to eq 1
-    end
-
-    def create_event(label)
-      create(:resource_label_event, issue: issue, label: label)
-    end
-  end
-end

spec/models/resource_label_event_spec.rb

@@ -96,4 +96,48 @@ RSpec.describe ResourceLabelEvent, type: :model do
       expect(subject.outdated_markdown?).to be false
     end
   end
+
+  describe '.visible_to_user?' do
+    let_it_be(:user) { create(:user) }
+    let_it_be(:issue_project) { create(:project) }
+    let_it_be(:issue) { create(:issue, project: issue_project) }
+
+    subject { described_class.visible_to_user?(user, issue.resource_label_events.inc_relations) }
+
+    it 'returns events with labels accessible by user' do
+      label = create(:label, project: issue_project)
+      event = create_event(label)
+      issue_project.add_guest(user)
+
+      expect(subject).to eq [event]
+    end
+
+    it 'filters events with public project labels if issues and MRs are private' do
+      project = create(:project, :public, :issues_private, :merge_requests_private)
+      label = create(:label, project: project)
+      create_event(label)
+
+      expect(subject).to be_empty
+    end
+
+    it 'filters events with project labels not accessible by user' do
+      project = create(:project, :private)
+      label = create(:label, project: project)
+      create_event(label)
+
+      expect(subject).to be_empty
+    end
+
+    it 'filters events with group labels not accessible by user' do
+      group = create(:group, :private)
+      label = create(:group_label, group: group)
+      create_event(label)
+
+      expect(subject).to be_empty
+    end
+
+    def create_event(label)
+      create(:resource_label_event, issue: issue, label: label)
+    end
+  end
 end

spec/support/shared_examples/requests/api/resource_label_events_api_shared_examples.rb

@@ -93,6 +93,20 @@ RSpec.shared_examples 'resource_label_events API' do |parent_type, eventable_typ
     end
   end
 
+  describe 'pagination' do
+    let!(:event1) { create_event(label) }
+    let!(:event2) { create_event(label) }
+
+    # https://gitlab.com/gitlab-org/gitlab/-/issues/220192
+    it "returns the second page" do
+      get api("/#{parent_type}/#{parent.id}/#{eventable_type}/#{eventable[id_name]}/resource_label_events?page=2&per_page=1", user)
+
+      expect(response).to have_gitlab_http_status(:ok)
+      expect(json_response.count).to eq(1)
+      expect(json_response.first['id']).to eq(event2.id)
+    end
+  end
+
   def create_event(label)
     create(:resource_label_event, eventable.class.name.underscore => eventable, label: label)
   end