Validate historical active user count when uploading license.

app/controllers/admin/licenses_controller.rb

@@ -5,6 +5,7 @@ class Admin::LicensesController < Admin::ApplicationController
   respond_to :html
 
   def show
+    @historical_active_user_count = HistoricalData.during(license.issued_at..Date.today).maximum(:active_user_count)
     @previous_licenses = License.previous
   end
 

app/models/license.rb

@@ -96,12 +96,26 @@ class License < ActiveRecord::Base
     restricted_user_count = self.restrictions[:active_user_count]
     active_user_count     = User.active.count
 
-    return if active_user_count <= restricted_user_count
+    if active_user_count > restricted_user_count
+      message = "This license allows #{restricted_user_count} active users. "
+      message << "This GitLab installation currently has #{active_user_count}, "
+      message << "i.e. #{active_user_count - restricted_user_count} too many."
 
-    message = "This license allows #{restricted_user_count} active users. "
-    message << "This GitLab installation currently has #{active_user_count}, "
-    message << "i.e. #{active_user_count - restricted_user_count} too many."
-    self.errors.add(:base, message)
+      self.errors.add(:base, message)
+      return
+    end
+
+    if License.current
+      historical_active_user_count = HistoricalData.during(License.current.issued_at..Date.today).maximum(:active_user_count)
+
+      if historical_active_user_count && historical_active_user_count > restricted_user_count
+        message = "This license allows #{restricted_user_count} active users. "
+        message << "At one point during the life of the previous license, this GitLab installation had "
+        message << "#{historical_active_user_count} active users, "
+        message << "i.e. #{historical_active_user_count - restricted_user_count} too many."
+        self.errors.add(:base, message)
+      end
+    end
   end
 
   def not_expired

app/views/admin/licenses/show.html.haml

@@ -49,19 +49,21 @@
           %span.light Active users:
           %strong
             - if @license.restricted?(:active_user_count)
-              - restricted_user_count = @license.restrictions[:active_user_count]
-              - active_user_count = User.active.count
-              #{restricted_user_count} users
+              - restricted = @license.restrictions[:active_user_count]
+              - current = User.active.count
+              - historical = @historical_active_user_count
 
-              - if active_user_count > restricted_user_count
-                %span.label.label-danger.pull-right
-                  %strong Exceeded by #{active_user_count - restricted_user_count} users
-              - elsif restricted_user_count > active_user_count
-                %span.label.label-success.pull-right
-                  %strong #{restricted_user_count - active_user_count} more allowed
-              - else
-                %span.label.label-info.pull-right
-                  %strong Right at the limit
+              #{restricted} users
+
+              - if historical && historical > restricted
+                %span.label.label-danger.pull-right.prepend-left-10
+                  %strong 
+                    Maximum during license life: #{historical} users
+
+              - label_class = current > restricted ? "danger" : restricted > current ? "success" : "info"
+              %span.label.pull-right{class: "label-#{label_class}"}
+                %strong 
+                  Current: #{current} users
 
             - else
               Unlimited

spec/factories.rb

@@ -204,7 +204,7 @@ FactoryGirl.define do
   end
 
   factory :gitlab_license, class: "Gitlab::License" do
-    issued_at { Date.today }
+    issued_at { Date.today - 1.month }
     licensee do 
       { "Name" => Faker::Name.name }
     end

spec/models/license_spec.rb

@@ -24,6 +24,39 @@ describe License do
     end
 
     describe "Active user count" do
+      let(:active_user_count) { User.active.count }
+
+      context "when there is no active user count restriction" do
+        it "is valid" do
+          expect(license).to be_valid
+        end
+      end
+
+      context "when the active user count restriction is exceeded" do
+        before do
+          gl_license.restrictions = { active_user_count: active_user_count - 1 }
+        end
+
+        it "is invalid" do
+          expect(license).to_not be_valid
+        end
+      end
+
+      context "when the active user count restriction is not exceeded" do
+        before do
+          gl_license.restrictions = { active_user_count: active_user_count + 1 }
+        end
+
+        it "is valid" do
+          expect(license).to be_valid
+        end
+      end
+    end
+
+    describe "Historical active user count" do
+      let(:active_user_count) { User.active.count + 10 }
+      let!(:historical_data)  { HistoricalData.create!(date: License.current.issued_at, active_user_count: active_user_count) }
+
       context "when there is no active user count restriction" do
         it "is valid" do
           expect(license).to be_valid
@@ -32,7 +65,7 @@ describe License do
 
       context "when the active user count restriction is exceeded" do
         before do
-          gl_license.restrictions = { active_user_count: User.active.count - 1 }
+          gl_license.restrictions = { active_user_count: active_user_count - 1 }
         end
 
         it "is invalid" do
@@ -42,7 +75,7 @@ describe License do
 
       context "when the active user count restriction is not exceeded" do
         before do
-          gl_license.restrictions = { active_user_count: User.active.count + 1 }
+          gl_license.restrictions = { active_user_count: active_user_count + 1 }
         end
 
         it "is valid" do