Fetch cycle analytics data for a specific date range.

1. Supported date ranges are 30 / 90 days ago. The default is 90 days
   ago.

2. All issues created before "x days ago" are filtered out, even if they
   have other related data (test runs, merge requests) within the filter
   range.

app/controllers/projects/cycle_analytics_controller.rb

 class Projects::CycleAnalyticsController < Projects::ApplicationController
   def show
-    @cycle_analytics = CycleAnalytics.new(@project)
+    @cycle_analytics = CycleAnalytics.new(@project, from: parse_start_date)
+  end
+
+  private
+
+  def parse_start_date
+    case cycle_analytics_params[:start_date]
+    when '30' then 30.days.ago
+    when '90' then 90.days.ago
+    else 90.days.ago
+    end
+  end
+
+  def cycle_analytics_params
+    return {} unless params[:cycle_analytics].present?
+
+    { start_date: params[:cycle_analytics][:start_date] }
   end
 end

app/models/cycle_analytics.rb

 class CycleAnalytics
-  def initialize(project)
+  attr_reader :from
+
+  def initialize(project, from:)
     @project = project
+    @from = from
   end
 
   def issue
-    calculate_metric(Queries::issues(@project),
+    calculate_metric(Queries::issues(@project, created_after: @from),
                      -> (data_point) { data_point[:issue].created_at },
                      [Queries::issue_first_associated_with_milestone_at, Queries::issue_first_added_to_list_label_at])
   end
 
   def plan
-    calculate_metric(Queries::issues(@project),
+    calculate_metric(Queries::issues(@project, created_after: @from),
                      [Queries::issue_first_associated_with_milestone_at, Queries::issue_first_added_to_list_label_at],
                      Queries::issue_closing_merge_request_opened_at)
   end
 
   def code
-    calculate_metric(Queries::merge_requests_closing_issues(@project),
+    calculate_metric(Queries::merge_requests_closing_issues(@project, created_after: @from),
                      -> (data_point) { data_point[:merge_request].created_at },
                      [Queries::merge_request_first_assigned_to_user_other_than_author_at, Queries::merge_request_wip_flag_first_removed_at])
   end
 
   def test
-    calculate_metric(Queries::merge_requests_closing_issues(@project),
+    calculate_metric(Queries::merge_requests_closing_issues(@project, created_after: @from),
                      Queries::merge_request_build_started_at,
                      Queries::merge_request_build_finished_at)
   end
 
   def review
-    calculate_metric(Queries::merge_requests_closing_issues(@project),
+    calculate_metric(Queries::merge_requests_closing_issues(@project, created_after: @from),
                      [Queries::merge_request_first_assigned_to_user_other_than_author_at, Queries::merge_request_wip_flag_first_removed_at],
                      [Queries::merge_request_first_closed_at, Queries::merge_request_merged_at])
   end
 
   def staging
-    calculate_metric(Queries::merge_requests_closing_issues(@project),
+    calculate_metric(Queries::merge_requests_closing_issues(@project, created_after: @from),
                      Queries::merge_request_merged_at,
                      Queries::merge_request_deployed_to_any_environment_at)
   end
 
   def production
-    calculate_metric(Queries::merge_requests_closing_issues(@project),
+    calculate_metric(Queries::merge_requests_closing_issues(@project, created_after: @from),
                      -> (data_point) { data_point[:issue].created_at },
                      Queries::merge_request_deployed_to_production_at)
   end

app/models/cycle_analytics/queries.rb

 class CycleAnalytics
   module Queries
     class << self
-      def issues(project)
-        project.issues.map { |issue| { issue: issue } }
+      def issues(project, created_after:)
+        project.issues.where("created_at >= ?", created_after).map { |issue| { issue: issue } }
       end
 
-      def merge_requests_closing_issues(project)
-        issues(project).map do |data_point|
+      def merge_requests_closing_issues(project, options = {})
+        issues(project, options).map do |data_point|
           merge_requests = data_point[:issue].closed_by_merge_requests(nil, check_if_open: false)
           merge_requests.map { |merge_request| { issue: data_point[:issue], merge_request: merge_request } }
         end.flatten

app/views/projects/cycle_analytics/show.html.haml

+%h2 Cycle Analytics from #{@cycle_analytics.from} to Today
+
 %ul.list-group
   %li.list-group-item
     Issue:

spec/models/cycle_analytics/issue_spec.rb

@@ -2,7 +2,8 @@ require 'spec_helper'
 
 describe 'CycleAnalytics#issue', models: true do
   let(:project) { create(:project) }
-  subject { CycleAnalytics.new(project) }
+  let(:from_date) { 10.days.ago }
+  subject { CycleAnalytics.new(project, from: from_date) }
 
   context "when calculating the median of times between:
                start: issue created_at
@@ -26,16 +27,6 @@ describe 'CycleAnalytics#issue', models: true do
         median_start_time, median_end_time = start_and_end_times[2]
         expect(subject.issue).to eq(median_end_time - median_start_time)
       end
-
-      it "does not include issues from other projects" do
-        5.times do
-          milestone = create(:milestone, project: project)
-          issue = create(:issue)
-          issue.update(milestone: milestone)
-        end
-
-        expect(subject.issue).to be_nil
-      end
     end
 
     context "when a label is added to the issue" do
@@ -80,6 +71,29 @@ describe 'CycleAnalytics#issue', models: true do
 
         expect(subject.issue).to eq(milestone_add_time - start_time)
       end
+
+
+      it "does not include issues from other projects" do
+        milestone = create(:milestone, project: project)
+        list_label = create(:label, lists: [create(:list)])
+        issue = create(:issue)
+        issue.update(milestone: milestone)
+        issue.update(label_ids: [list_label.id])
+
+        expect(subject.issue).to be_nil
+      end
+
+      it "excludes issues created before the 'from' date" do
+        before_from_date = from_date - 5.days
+
+        milestone = create(:milestone, project: project)
+        list_label = create(:label, lists: [create(:list)])
+        issue = Timecop.freeze(before_from_date) { create(:issue, project: project)}
+        issue.update(milestone: milestone)
+        issue.update(label_ids: [list_label.id])
+
+        expect(subject.issue).to be_nil
+      end
     end
   end
 end