Merge branch 'milestone-burnup-charts-graphql' into 'master'

Add milestone burnup charts to GraphQL

See merge request gitlab-org/gitlab!38672

app/graphql/types/milestone_type.rb

@@ -60,3 +60,5 @@ module Types
     end
   end
 end
+
+Types::MilestoneType.prepend_if_ee('::EE::Types::MilestoneType')

doc/api/graphql/reference/gitlab_schema.graphql

@@ -1427,6 +1427,36 @@ type Branch {
   name: String!
 }
 
+"""
+Represents the total number of issues and their weights for a particular day.
+"""
+type BurnupChartDailyTotals {
+  """
+  Number of closed issues as of this day
+  """
+  completedCount: Int!
+
+  """
+  Total weight of closed issues as of this day
+  """
+  completedWeight: Int!
+
+  """
+  Date for burnup totals
+  """
+  date: ISO8601Date!
+
+  """
+  Number of issues as of this day
+  """
+  scopeCount: Int!
+
+  """
+  Total weight of issues as of this day
+  """
+  scopeWeight: Int!
+}
+
 type CiGroup {
   """
   Jobs in group
@@ -9549,6 +9579,11 @@ type MetricsDashboardAnnotationEdge {
 Represents a milestone.
 """
 type Milestone {
+  """
+  Daily scope and completed totals for burnup charts
+  """
+  burnupTimeSeries: [BurnupChartDailyTotals!]
+
   """
   Timestamp of milestone creation
   """

doc/api/graphql/reference/gitlab_schema.json

@@ -3851,6 +3851,109 @@
           "enumValues": null,
           "possibleTypes": null
         },
+        {
+          "kind": "OBJECT",
+          "name": "BurnupChartDailyTotals",
+          "description": "Represents the total number of issues and their weights for a particular day.",
+          "fields": [
+            {
+              "name": "completedCount",
+              "description": "Number of closed issues as of this day",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "NON_NULL",
+                "name": null,
+                "ofType": {
+                  "kind": "SCALAR",
+                  "name": "Int",
+                  "ofType": null
+                }
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            },
+            {
+              "name": "completedWeight",
+              "description": "Total weight of closed issues as of this day",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "NON_NULL",
+                "name": null,
+                "ofType": {
+                  "kind": "SCALAR",
+                  "name": "Int",
+                  "ofType": null
+                }
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            },
+            {
+              "name": "date",
+              "description": "Date for burnup totals",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "NON_NULL",
+                "name": null,
+                "ofType": {
+                  "kind": "SCALAR",
+                  "name": "ISO8601Date",
+                  "ofType": null
+                }
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            },
+            {
+              "name": "scopeCount",
+              "description": "Number of issues as of this day",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "NON_NULL",
+                "name": null,
+                "ofType": {
+                  "kind": "SCALAR",
+                  "name": "Int",
+                  "ofType": null
+                }
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            },
+            {
+              "name": "scopeWeight",
+              "description": "Total weight of issues as of this day",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "NON_NULL",
+                "name": null,
+                "ofType": {
+                  "kind": "SCALAR",
+                  "name": "Int",
+                  "ofType": null
+                }
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            }
+          ],
+          "inputFields": null,
+          "interfaces": [
+
+          ],
+          "enumValues": null,
+          "possibleTypes": null
+        },
         {
           "kind": "OBJECT",
           "name": "CiGroup",
@@ -26709,6 +26812,28 @@
           "name": "Milestone",
           "description": "Represents a milestone.",
           "fields": [
+            {
+              "name": "burnupTimeSeries",
+              "description": "Daily scope and completed totals for burnup charts",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "LIST",
+                "name": null,
+                "ofType": {
+                  "kind": "NON_NULL",
+                  "name": null,
+                  "ofType": {
+                    "kind": "OBJECT",
+                    "name": "BurnupChartDailyTotals",
+                    "ofType": null
+                  }
+                }
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            },
             {
               "name": "createdAt",
               "description": "Timestamp of milestone creation",

doc/api/graphql/reference/index.md

@@ -245,6 +245,18 @@ Autogenerated return type of BoardListUpdateLimitMetrics
 | `commit` | Commit | Commit for the branch |
 | `name` | String! | Name of the branch |
 
+## BurnupChartDailyTotals
+
+Represents the total number of issues and their weights for a particular day.
+
+| Name  | Type  | Description |
+| ---   |  ---- | ----------  |
+| `completedCount` | Int! | Number of closed issues as of this day |
+| `completedWeight` | Int! | Total weight of closed issues as of this day |
+| `date` | ISO8601Date! | Date for burnup totals |
+| `scopeCount` | Int! | Number of issues as of this day |
+| `scopeWeight` | Int! | Total weight of issues as of this day |
+
 ## CiGroup
 
 | Name  | Type  | Description |
@@ -1477,6 +1489,7 @@ Represents a milestone.
 
 | Name  | Type  | Description |
 | ---   |  ---- | ----------  |
+| `burnupTimeSeries` | BurnupChartDailyTotals! => Array | Daily scope and completed totals for burnup charts |
 | `createdAt` | Time! | Timestamp of milestone creation |
 | `description` | String | Description of the milestone |
 | `dueDate` | Time | Timestamp of the milestone due date |

ee/app/graphql/ee/types/milestone_type.rb

+# frozen_string_literal: true
+
+module EE
+  module Types
+    module MilestoneType
+      extend ActiveSupport::Concern
+
+      prepended do
+        field :burnup_time_series, [::Types::BurnupChartDailyTotalsType], null: true,
+              resolver: ::Resolvers::MilestoneBurnupTimeSeriesResolver,
+              description: 'Daily scope and completed totals for burnup charts',
+              complexity: 175
+      end
+    end
+  end
+end

ee/app/graphql/resolvers/milestone_burnup_time_series_resolver.rb

+# frozen_string_literal: true
+
+module Resolvers
+  class MilestoneBurnupTimeSeriesResolver < BaseResolver
+    type [Types::BurnupChartDailyTotalsType], null: true
+
+    alias_method :milestone, :synchronized_object
+
+    def resolve(*args)
+      return [] unless milestone.burnup_charts_available?
+
+      response = Milestones::BurnupChartService.new(milestone).execute
+
+      raise GraphQL::ExecutionError, response.message if response.error?
+
+      response.payload
+    end
+  end
+end

ee/app/graphql/types/burnup_chart_daily_totals_type.rb

+# frozen_string_literal: true
+
+module Types
+  # rubocop: disable Graphql/AuthorizeTypes
+  class BurnupChartDailyTotalsType < BaseObject
+    graphql_name 'BurnupChartDailyTotals'
+    description 'Represents the total number of issues and their weights for a particular day.'
+
+    field :date, GraphQL::Types::ISO8601Date, null: false,
+          description: 'Date for burnup totals'
+
+    field :scope_count, GraphQL::INT_TYPE, null: false,
+          description: 'Number of issues as of this day'
+
+    field :scope_weight, GraphQL::INT_TYPE, null: false,
+          description: 'Total weight of issues as of this day'
+
+    field :completed_count, GraphQL::INT_TYPE, null: false,
+          description: 'Number of closed issues as of this day'
+
+    field :completed_weight, GraphQL::INT_TYPE, null: false,
+          description: 'Total weight of closed issues as of this day'
+  end
+end

ee/app/models/ee/milestone.rb

@@ -20,6 +20,10 @@ module EE
       resource_parent&.feature_available?(feature_name) && supports_weight?
     end
 
+    def supports_burnup_charts?
+      resource_parent&.feature_available?(:milestone_charts) && supports_weight?
+    end
+
     def burnup_charts_available?
       ::Feature.enabled?(:burnup_charts, resource_parent)
     end

ee/app/models/license.rb

@@ -28,6 +28,7 @@ class License < ApplicationRecord
     ldap_group_sync
     member_lock
     merge_request_approvers
+    milestone_charts
     multiple_issue_assignees
     multiple_ldap_servers
     multiple_merge_request_assignees

ee/app/services/milestones/burnup_chart_service.rb

@@ -12,20 +12,18 @@ class Milestones::BurnupChartService
 
   EVENT_COUNT_LIMIT = 50_000
 
-  TooManyEventsError = Class.new(StandardError)
-
   def initialize(milestone)
-    raise ArgumentError, 'Milestone must have a start and due date' if milestone.start_date.blank? || milestone.due_date.blank?
-
     @milestone = milestone
   end
 
   def execute
+    return ServiceResponse.error(message: _('Milestone does not support burnup charts')) unless milestone.supports_burnup_charts?
+    return ServiceResponse.error(message: _('Milestone must have a start and due date')) if milestone.start_date.blank? || milestone.due_date.blank?
+    return ServiceResponse.error(message: _('Burnup chart could not be generated due to too many events')) if resource_events.num_tuples > EVENT_COUNT_LIMIT
+
     @issue_states = {}
     @chart_data = []
 
-    raise TooManyEventsError if resource_events.num_tuples > EVENT_COUNT_LIMIT
-
     resource_events.each do |event|
       case event['event_type']
       when 'milestone'
@@ -37,7 +35,7 @@ class Milestones::BurnupChartService
       end
     end
 
-    chart_data
+    ServiceResponse.success(payload: chart_data)
   end
 
   private

ee/spec/graphql/ee/types/milestone_type_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe GitlabSchema.types['Milestone'] do
+  it { expect(described_class).to have_graphql_field(:burnup_time_series) }
+end

ee/spec/graphql/resolvers/milestone_burnup_time_series_resolver_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Resolvers::MilestoneBurnupTimeSeriesResolver do
+  include GraphqlHelpers
+
+  let_it_be(:project) { create(:project) }
+  let_it_be(:milestone) { create(:milestone, project: project, start_date: '2020-01-01', due_date: '2020-01-15') }
+  let_it_be(:issues) { create_list(:issue, 2, project: project) }
+
+  before_all do
+    create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2020-01-05')
+    create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2020-01-10')
+  end
+
+  before do
+    stub_licensed_features(milestone_charts: true, issue_weights: true)
+  end
+
+  subject { resolve(described_class, obj: milestone) }
+
+  context 'when the feature flag is disabled' do
+    before do
+      stub_feature_flags(burnup_charts: false)
+    end
+
+    it 'returns empty data' do
+      expect(subject).to be_empty
+    end
+  end
+
+  context 'when the feature flag is enabled' do
+    before do
+      stub_feature_flags(burnup_charts: true)
+    end
+
+    it 'returns burnup chart data' do
+      expect(subject).to eq([
+        {
+          date: Date.parse('2020-01-05'),
+          scope_count: 1,
+          scope_weight: 0,
+          completed_count: 0,
+          completed_weight: 0
+        },
+        {
+          date: Date.parse('2020-01-10'),
+          scope_count: 2,
+          scope_weight: 0,
+          completed_count: 0,
+          completed_weight: 0
+        }
+      ])
+    end
+
+    context 'when the service returns an error' do
+      before do
+        stub_const('Milestones::BurnupChartService::EVENT_COUNT_LIMIT', 1)
+      end
+
+      it 'raises a GraphQL exception' do
+        expect { subject }.to raise_error(GraphQL::ExecutionError, 'Burnup chart could not be generated due to too many events')
+      end
+    end
+  end
+end

ee/spec/graphql/types/burnup_chart_daily_totals_type_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe GitlabSchema.types['BurnupChartDailyTotals'] do
+  it { expect(described_class.graphql_name).to eq('BurnupChartDailyTotals') }
+
+  it 'has specific fields' do
+    expect(described_class).to have_graphql_fields(
+      :date,
+      :scope_count,
+      :scope_weight,
+      :completed_count,
+      :completed_weight
+    )
+  end
+end

ee/spec/requests/api/graphql/milestone_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe 'Querying a Milestone' do
+  include GraphqlHelpers
+
+  let_it_be(:current_user) { create(:user) }
+  let_it_be(:project) { create(:project) }
+  let_it_be(:milestone) { create(:milestone, project: project, start_date: '2020-01-01', due_date: '2020-01-15') }
+
+  let(:query) do
+    graphql_query_for('milestone', { id: milestone.to_global_id.to_s }, fields)
+  end
+
+  subject { graphql_data['milestone'] }
+
+  before_all do
+    project.add_guest(current_user)
+  end
+
+  context 'burnupTimeSeries' do
+    let(:fields) do
+      <<~FIELDS
+      burnupTimeSeries {
+        date
+        scopeCount
+        scopeWeight
+        completedCount
+        completedWeight
+      }
+      FIELDS
+    end
+
+    let_it_be(:issue) { create(:issue, project: project) }
+
+    before_all do
+      create(:resource_milestone_event, issue: issue, milestone: milestone, action: :add, created_at: '2020-01-05')
+    end
+
+    context 'when feature flag is enabled' do
+      before do
+        stub_feature_flags(burnup_charts: true)
+      end
+
+      context 'with insufficient license' do
+        before do
+          stub_licensed_features(milestone_charts: false)
+        end
+
+        it 'returns an error' do
+          post_graphql(query, current_user: current_user)
+
+          expect(graphql_errors).to include(a_hash_including('message' => 'Milestone does not support burnup charts'))
+        end
+      end
+
+      context 'with correct license' do
+        before do
+          stub_licensed_features(milestone_charts: true, issue_weights: true)
+        end
+
+        it 'returns burnup chart data' do
+          post_graphql(query, current_user: current_user)
+
+          expect(subject).to eq({
+            'burnupTimeSeries' => [
+              {
+                'date' => '2020-01-05',
+                'scopeCount' => 1,
+                'scopeWeight' => 0,
+                'completedCount' => 0,
+                'completedWeight' => 0
+              }
+            ]
+          })
+        end
+      end
+    end
+
+    context 'when feature flag is disabled' do
+      before do
+        stub_feature_flags(burnup_charts: false)
+        stub_licensed_features(milestone_charts: true, issue_weights: true)
+      end
+
+      it 'returns empty results' do
+        post_graphql(query, current_user: current_user)
+
+        expect(subject).to eq({ 'burnupTimeSeries' => [] })
+      end
+    end
+  end
+end

ee/spec/services/milestones/burnup_chart_service_spec.rb

@@ -4,249 +4,274 @@ require 'spec_helper'
 
 RSpec.describe Milestones::BurnupChartService do
   let_it_be(:project) { create(:project) }
-  let_it_be(:milestone) { create(:milestone, project: project, start_date: '2020-01-01', due_date: '2020-01-15') }
+  let_it_be(:milestone, reload: true) { create(:milestone, project: project, start_date: '2020-01-01', due_date: '2020-01-15') }
 
   let_it_be(:issues) { create_list(:issue, 5, project: project) }
 
-  let(:chart_data) { described_class.new(milestone).execute }
+  let(:response) { described_class.new(milestone).execute }
 
-  it 'raises an error when milestone does not have a start and due date' do
-    milestone = build(:milestone, project: project)
+  context 'when license is not available' do
+    before do
+      stub_licensed_features(milestone_charts: false)
+    end
 
-    expect { described_class.new(milestone) }.to raise_error('Milestone must have a start and due date')
+    it 'returns an error message' do
+      expect(response.error?).to eq(true)
+      expect(response.message).to eq('Milestone does not support burnup charts')
+    end
   end
 
-  it 'raises an error when the number of events exceeds the limit' do
-    stub_const('Milestones::BurnupChartService::EVENT_COUNT_LIMIT', 1)
-
-    create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2019-12-15')
-    create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2019-12-16')
-
-    expect { chart_data }.to raise_error(described_class::TooManyEventsError)
-  end
-
-  it 'aggregates events before the start date to the start date' do
-    create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2019-12-15')
-    create(:resource_weight_event, issue: issues[0], weight: 2, created_at: '2019-12-18')
-
-    create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2019-12-16')
-    create(:resource_weight_event, issue: issues[1], weight: 1, created_at: '2019-12-18')
-
-    create(:resource_milestone_event, issue: issues[2], milestone: milestone, action: :add, created_at: '2019-12-16')
-    create(:resource_weight_event, issue: issues[2], weight: 3, created_at: '2019-12-18')
-    create(:resource_state_event, issue: issues[2], state: :closed, created_at: '2019-12-25')
-
-    create(:resource_milestone_event, issue: issues[3], milestone: milestone, action: :add, created_at: '2019-12-17')
-    create(:resource_weight_event, issue: issues[3], weight: 4, created_at: '2019-12-18')
-    create(:resource_state_event, issue: issues[3], state: :closed, created_at: '2019-12-26')
-
-    expect(chart_data).to eq([
-      {
-        date: Date.parse('2020-01-01'),
-        scope_count: 4,
-        scope_weight: 10,
-        completed_count: 2,
-        completed_weight: 7
-      }
-    ])
-  end
-
-  it 'updates counts and weight when the milestone is added or removed' do
-    # Add milestone to an open issue with no weight.
-    create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2020-01-05 03:00')
-    # Ignore duplicate add event.
-    create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2020-01-05 03:00')
-
-    # Add milestone to an open issue with weight 2 on the same day. This should increment the scope totals for the same day.
-    create(:resource_weight_event, issue: issues[1], weight: 2, created_at: '2020-01-01')
-    create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2020-01-05 05:00')
-
-    # Add milestone to already closed issue with weight 3. This should increment both the scope and completed totals.
-    create(:resource_weight_event, issue: issues[2], weight: 3, created_at: '2020-01-01')
-    create(:resource_state_event, issue: issues[2], state: :closed, created_at: '2020-01-05')
-    create(:resource_milestone_event, issue: issues[2], milestone: milestone, action: :add, created_at: '2020-01-06')
-
-    # Remove milestone from the 2nd open issue. This should decrement the scope totals.
-    create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :remove, created_at: '2020-01-07')
-
-    # Remove milestone from the closed issue. This should decrement both the scope and completed totals.
-    create(:resource_milestone_event, issue: issues[2], milestone: milestone, action: :remove, created_at: '2020-01-08')
-
-    # Adding a different milestone should not affect the data.
-    create(:resource_milestone_event, issue: issues[3], milestone: create(:milestone, project: project), action: :add, created_at: '2020-01-08')
-
-    # Adding the milestone after the due date should not affect the data.
-    create(:resource_milestone_event, issue: issues[4], milestone: milestone, action: :add, created_at: '2020-01-30')
-
-    # Removing the milestone after the due date should not affect the data.
-    create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :remove, created_at: '2020-01-30')
-
-    expect(chart_data).to eq([
-      {
-        date: Date.parse('2020-01-05'),
-        scope_count: 2,
-        scope_weight: 2,
-        completed_count: 0,
-        completed_weight: 0
-      },
-      {
-        date: Date.parse('2020-01-06'),
-        scope_count: 3,
-        scope_weight: 5,
-        completed_count: 1,
-        completed_weight: 3
-      },
-      {
-        date: Date.parse('2020-01-07'),
-        scope_count: 2,
-        scope_weight: 3,
-        completed_count: 1,
-        completed_weight: 3
-      },
-      {
-        date: Date.parse('2020-01-08'),
-        scope_count: 1,
-        scope_weight: 0,
-        completed_count: 0,
-        completed_weight: 0
-      }
-    ])
-  end
-
-  it 'updates the completed counts when issue state is changed' do
-    # Close an issue assigned to the milestone with weight 2. This should increment the completed totals.
-    create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2020-01-01 01:00')
-    create(:resource_weight_event, issue: issues[0], weight: 2, created_at: '2020-01-01 02:00')
-    create(:resource_state_event, issue: issues[0], state: :closed, created_at: '2020-01-02')
-
-    # Closing an issue that is already closed should be ignored.
-    create(:resource_state_event, issue: issues[0], state: :closed, created_at: '2020-01-03')
-
-    # Re-opening the issue should decrement the completed totals.
-    create(:resource_state_event, issue: issues[0], state: :reopened, created_at: '2020-01-04')
-
-    # Closing and re-opening an issue on the same day should not change the totals.
-    create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2020-01-05 01:00')
-    create(:resource_weight_event, issue: issues[1], weight: 3, created_at: '2020-01-05 02:00')
-    create(:resource_state_event, issue: issues[1], state: :closed, created_at: '2020-01-06 05:00')
-    create(:resource_state_event, issue: issues[1], state: :reopened, created_at: '2020-01-06 08:00')
-
-    # Re-opening an issue that is already open should be ignored.
-    create(:resource_state_event, issue: issues[1], state: :reopened, created_at: '2020-01-07')
-
-    # Closing a re-opened issue should increment the completed totals.
-    create(:resource_state_event, issue: issues[1], state: :closed, created_at: '2020-01-08')
-
-    # Changing state when the milestone is already removed should not affect the data.
-    create(:resource_milestone_event, issue: issues[1], action: :remove, created_at: '2020-01-09')
-    create(:resource_state_event, issue: issues[1], state: :closed, created_at: '2020-01-10')
-
-    expect(chart_data).to eq([
-      {
-        date: Date.parse('2020-01-01'),
-        scope_count: 1,
-        scope_weight: 2,
-        completed_count: 0,
-        completed_weight: 0
-      },
-      {
-        date: Date.parse('2020-01-02'),
-        scope_count: 1,
-        scope_weight: 2,
-        completed_count: 1,
-        completed_weight: 2
-      },
-      {
-        date: Date.parse('2020-01-04'),
-        scope_count: 1,
-        scope_weight: 2,
-        completed_count: 0,
-        completed_weight: 0
-      },
-      {
-        date: Date.parse('2020-01-05'),
-        scope_count: 2,
-        scope_weight: 5,
-        completed_count: 0,
-        completed_weight: 0
-      },
-      {
-        date: Date.parse('2020-01-06'),
-        scope_count: 2,
-        scope_weight: 5,
-        completed_count: 0,
-        completed_weight: 0
-      },
-      {
-        date: Date.parse('2020-01-08'),
-        scope_count: 2,
-        scope_weight: 5,
-        completed_count: 1,
-        completed_weight: 3
-      },
-      {
-        date: Date.parse('2020-01-09'),
-        scope_count: 1,
-        scope_weight: 2,
-        completed_count: 0,
-        completed_weight: 0
-      }
-    ])
-  end
-
-  it 'updates the weight totals when issue weight is changed' do
-    # Issue starts out with no weight and should increment once the weight is changed to 2.
-    create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2020-01-01')
-    create(:resource_weight_event, issue: issues[0], weight: 2, created_at: '2020-01-02')
-
-    # A closed issue is added and weight is set to 5 and should add to the weight totals.
-    create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2020-01-03 01:00')
-    create(:resource_state_event, issue: issues[1], state: :closed, created_at: '2020-01-03 02:00')
-    create(:resource_weight_event, issue: issues[1], weight: 5, created_at: '2020-01-03 03:00')
-
-    # Lowering the weight of the 2nd issue should decrement the weight totals.
-    create(:resource_weight_event, issue: issues[1], weight: 1, created_at: '2020-01-04')
-
-    # After the first issue is assigned to another milestone, weight changes shouldn't affect the data.
-    create(:resource_milestone_event, issue: issues[0], milestone: create(:milestone, project: project), action: :add, created_at: '2020-01-05')
-    create(:resource_weight_event, issue: issues[0], weight: 10, created_at: '2020-01-06')
-
-    expect(chart_data).to eq([
-      {
-        date: Date.parse('2020-01-01'),
-        scope_count: 1,
-        scope_weight: 0,
-        completed_count: 0,
-        completed_weight: 0
-      },
-      {
-        date: Date.parse('2020-01-02'),
-        scope_count: 1,
-        scope_weight: 2,
-        completed_count: 0,
-        completed_weight: 0
-      },
-      {
-        date: Date.parse('2020-01-03'),
-        scope_count: 2,
-        scope_weight: 7,
-        completed_count: 1,
-        completed_weight: 5
-      },
-      {
-        date: Date.parse('2020-01-04'),
-        scope_count: 2,
-        scope_weight: 3,
-        completed_count: 1,
-        completed_weight: 1
-      },
-      {
-        date: Date.parse('2020-01-05'),
-        scope_count: 1,
-        scope_weight: 1,
-        completed_count: 1,
-        completed_weight: 1
-      }
-    ])
+  context 'when license is available' do
+    before do
+      stub_licensed_features(milestone_charts: true, issue_weights: true)
+    end
+
+    context 'when milestone does not have a start and due date' do
+      let(:milestone) { build(:milestone, project: project) }
+
+      it 'returns an error message' do
+        expect(response.error?).to eq(true)
+        expect(response.message).to eq('Milestone must have a start and due date')
+      end
+    end
+
+    it 'returns an error when the number of events exceeds the limit' do
+      stub_const('Milestones::BurnupChartService::EVENT_COUNT_LIMIT', 1)
+
+      create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2019-12-15')
+      create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2019-12-16')
+
+      expect(response.error?).to eq(true)
+      expect(response.message).to eq('Burnup chart could not be generated due to too many events')
+    end
+
+    it 'aggregates events before the start date to the start date' do
+      create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2019-12-15')
+      create(:resource_weight_event, issue: issues[0], weight: 2, created_at: '2019-12-18')
+
+      create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2019-12-16')
+      create(:resource_weight_event, issue: issues[1], weight: 1, created_at: '2019-12-18')
+
+      create(:resource_milestone_event, issue: issues[2], milestone: milestone, action: :add, created_at: '2019-12-16')
+      create(:resource_weight_event, issue: issues[2], weight: 3, created_at: '2019-12-18')
+      create(:resource_state_event, issue: issues[2], state: :closed, created_at: '2019-12-25')
+
+      create(:resource_milestone_event, issue: issues[3], milestone: milestone, action: :add, created_at: '2019-12-17')
+      create(:resource_weight_event, issue: issues[3], weight: 4, created_at: '2019-12-18')
+      create(:resource_state_event, issue: issues[3], state: :closed, created_at: '2019-12-26')
+
+      expect(response.success?).to eq(true)
+      expect(response.payload).to eq([
+        {
+          date: Date.parse('2020-01-01'),
+          scope_count: 4,
+          scope_weight: 10,
+          completed_count: 2,
+          completed_weight: 7
+        }
+      ])
+    end
+
+    it 'updates counts and weight when the milestone is added or removed' do
+      # Add milestone to an open issue with no weight.
+      create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2020-01-05 03:00')
+      # Ignore duplicate add event.
+      create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2020-01-05 03:00')
+
+      # Add milestone to an open issue with weight 2 on the same day. This should increment the scope totals for the same day.
+      create(:resource_weight_event, issue: issues[1], weight: 2, created_at: '2020-01-01')
+      create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2020-01-05 05:00')
+
+      # Add milestone to already closed issue with weight 3. This should increment both the scope and completed totals.
+      create(:resource_weight_event, issue: issues[2], weight: 3, created_at: '2020-01-01')
+      create(:resource_state_event, issue: issues[2], state: :closed, created_at: '2020-01-05')
+      create(:resource_milestone_event, issue: issues[2], milestone: milestone, action: :add, created_at: '2020-01-06')
+
+      # Remove milestone from the 2nd open issue. This should decrement the scope totals.
+      create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :remove, created_at: '2020-01-07')
+
+      # Remove milestone from the closed issue. This should decrement both the scope and completed totals.
+      create(:resource_milestone_event, issue: issues[2], milestone: milestone, action: :remove, created_at: '2020-01-08')
+
+      # Adding a different milestone should not affect the data.
+      create(:resource_milestone_event, issue: issues[3], milestone: create(:milestone, project: project), action: :add, created_at: '2020-01-08')
+
+      # Adding the milestone after the due date should not affect the data.
+      create(:resource_milestone_event, issue: issues[4], milestone: milestone, action: :add, created_at: '2020-01-30')
+
+      # Removing the milestone after the due date should not affect the data.
+      create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :remove, created_at: '2020-01-30')
+
+      expect(response.success?).to eq(true)
+      expect(response.payload).to eq([
+        {
+          date: Date.parse('2020-01-05'),
+          scope_count: 2,
+          scope_weight: 2,
+          completed_count: 0,
+          completed_weight: 0
+        },
+        {
+          date: Date.parse('2020-01-06'),
+          scope_count: 3,
+          scope_weight: 5,
+          completed_count: 1,
+          completed_weight: 3
+        },
+        {
+          date: Date.parse('2020-01-07'),
+          scope_count: 2,
+          scope_weight: 3,
+          completed_count: 1,
+          completed_weight: 3
+        },
+        {
+          date: Date.parse('2020-01-08'),
+          scope_count: 1,
+          scope_weight: 0,
+          completed_count: 0,
+          completed_weight: 0
+        }
+      ])
+    end
+
+    it 'updates the completed counts when issue state is changed' do
+      # Close an issue assigned to the milestone with weight 2. This should increment the completed totals.
+      create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2020-01-01 01:00')
+      create(:resource_weight_event, issue: issues[0], weight: 2, created_at: '2020-01-01 02:00')
+      create(:resource_state_event, issue: issues[0], state: :closed, created_at: '2020-01-02')
+
+      # Closing an issue that is already closed should be ignored.
+      create(:resource_state_event, issue: issues[0], state: :closed, created_at: '2020-01-03')
+
+      # Re-opening the issue should decrement the completed totals.
+      create(:resource_state_event, issue: issues[0], state: :reopened, created_at: '2020-01-04')
+
+      # Closing and re-opening an issue on the same day should not change the totals.
+      create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2020-01-05 01:00')
+      create(:resource_weight_event, issue: issues[1], weight: 3, created_at: '2020-01-05 02:00')
+      create(:resource_state_event, issue: issues[1], state: :closed, created_at: '2020-01-06 05:00')
+      create(:resource_state_event, issue: issues[1], state: :reopened, created_at: '2020-01-06 08:00')
+
+      # Re-opening an issue that is already open should be ignored.
+      create(:resource_state_event, issue: issues[1], state: :reopened, created_at: '2020-01-07')
+
+      # Closing a re-opened issue should increment the completed totals.
+      create(:resource_state_event, issue: issues[1], state: :closed, created_at: '2020-01-08')
+
+      # Changing state when the milestone is already removed should not affect the data.
+      create(:resource_milestone_event, issue: issues[1], action: :remove, created_at: '2020-01-09')
+      create(:resource_state_event, issue: issues[1], state: :closed, created_at: '2020-01-10')
+
+      expect(response.success?).to eq(true)
+      expect(response.payload).to eq([
+        {
+          date: Date.parse('2020-01-01'),
+          scope_count: 1,
+          scope_weight: 2,
+          completed_count: 0,
+          completed_weight: 0
+        },
+        {
+          date: Date.parse('2020-01-02'),
+          scope_count: 1,
+          scope_weight: 2,
+          completed_count: 1,
+          completed_weight: 2
+        },
+        {
+          date: Date.parse('2020-01-04'),
+          scope_count: 1,
+          scope_weight: 2,
+          completed_count: 0,
+          completed_weight: 0
+        },
+        {
+          date: Date.parse('2020-01-05'),
+          scope_count: 2,
+          scope_weight: 5,
+          completed_count: 0,
+          completed_weight: 0
+        },
+        {
+          date: Date.parse('2020-01-06'),
+          scope_count: 2,
+          scope_weight: 5,
+          completed_count: 0,
+          completed_weight: 0
+        },
+        {
+          date: Date.parse('2020-01-08'),
+          scope_count: 2,
+          scope_weight: 5,
+          completed_count: 1,
+          completed_weight: 3
+        },
+        {
+          date: Date.parse('2020-01-09'),
+          scope_count: 1,
+          scope_weight: 2,
+          completed_count: 0,
+          completed_weight: 0
+        }
+      ])
+    end
+
+    it 'updates the weight totals when issue weight is changed' do
+      # Issue starts out with no weight and should increment once the weight is changed to 2.
+      create(:resource_milestone_event, issue: issues[0], milestone: milestone, action: :add, created_at: '2020-01-01')
+      create(:resource_weight_event, issue: issues[0], weight: 2, created_at: '2020-01-02')
+
+      # A closed issue is added and weight is set to 5 and should add to the weight totals.
+      create(:resource_milestone_event, issue: issues[1], milestone: milestone, action: :add, created_at: '2020-01-03 01:00')
+      create(:resource_state_event, issue: issues[1], state: :closed, created_at: '2020-01-03 02:00')
+      create(:resource_weight_event, issue: issues[1], weight: 5, created_at: '2020-01-03 03:00')
+
+      # Lowering the weight of the 2nd issue should decrement the weight totals.
+      create(:resource_weight_event, issue: issues[1], weight: 1, created_at: '2020-01-04')
+
+      # After the first issue is assigned to another milestone, weight changes shouldn't affect the data.
+      create(:resource_milestone_event, issue: issues[0], milestone: create(:milestone, project: project), action: :add, created_at: '2020-01-05')
+      create(:resource_weight_event, issue: issues[0], weight: 10, created_at: '2020-01-06')
+
+      expect(response.success?).to eq(true)
+      expect(response.payload).to eq([
+        {
+          date: Date.parse('2020-01-01'),
+          scope_count: 1,
+          scope_weight: 0,
+          completed_count: 0,
+          completed_weight: 0
+        },
+        {
+          date: Date.parse('2020-01-02'),
+          scope_count: 1,
+          scope_weight: 2,
+          completed_count: 0,
+          completed_weight: 0
+        },
+        {
+          date: Date.parse('2020-01-03'),
+          scope_count: 2,
+          scope_weight: 7,
+          completed_count: 1,
+          completed_weight: 5
+        },
+        {
+          date: Date.parse('2020-01-04'),
+          scope_count: 2,
+          scope_weight: 3,
+          completed_count: 1,
+          completed_weight: 1
+        },
+        {
+          date: Date.parse('2020-01-05'),
+          scope_count: 1,
+          scope_weight: 1,
+          completed_count: 1,
+          completed_weight: 1
+        }
+      ])
+    end
   end
 end

locale/gitlab.pot

@@ -4190,6 +4190,9 @@ msgstr ""
 msgid "Burnup chart"
 msgstr ""
 
+msgid "Burnup chart could not be generated due to too many events"
+msgstr ""
+
 msgid "Business"
 msgstr ""
 
@@ -15705,12 +15708,18 @@ msgid_plural "Milestones"
 msgstr[0] ""
 msgstr[1] ""
 
+msgid "Milestone does not support burnup charts"
+msgstr ""
+
 msgid "Milestone lists not available with your current license"
 msgstr ""
 
 msgid "Milestone lists show all issues from the selected milestone."
 msgstr ""
 
+msgid "Milestone must have a start and due date"
+msgstr ""
+
 msgid "MilestoneSidebar|Closed:"
 msgstr ""
 

spec/graphql/types/milestone_type_spec.rb

@@ -15,7 +15,7 @@ RSpec.describe GitlabSchema.types['Milestone'] do
       stats
     ]
 
-    expect(described_class).to have_graphql_fields(*expected_fields)
+    expect(described_class).to have_graphql_fields(*expected_fields).at_least
   end
 
   describe 'stats field' do