Allow disabling usage ping in `gitlab.yml`

app/models/application_setting.rb

@@ -246,7 +246,7 @@ class ApplicationSetting < ActiveRecord::Base
       two_factor_grace_period: 48,
       user_default_external: false,
       polling_interval_multiplier: 1,
-      usage_ping_enabled: true
+      usage_ping_enabled: Settings.gitlab['usage_ping_enabled']
     }
   end
 
@@ -349,6 +349,14 @@ class ApplicationSetting < ActiveRecord::Base
     sidekiq_throttling_enabled
   end
 
+  def usage_ping_can_be_configured?
+    Settings.gitlab.usage_ping_enabled
+  end
+
+  def usage_ping_enabled
+    usage_ping_can_be_configured? && super
+  end
+
   private
 
   def ensure_uuid!

app/views/admin/application_settings/_form.html.haml

@@ -502,17 +502,24 @@
             Let GitLab inform you when an update is available.
     .form-group
       .col-sm-offset-2.col-sm-10
+        - can_be_configured = @application_setting.usage_ping_can_be_configured?
         .checkbox
           = f.label :usage_ping_enabled do
-            = f.check_box :usage_ping_enabled
+            = f.check_box :usage_ping_enabled, disabled: !can_be_configured
             Usage ping enabled
-            = link_to icon('question-circle'), help_page_path("user/admin_area/settings/usage_statistics", anchor: "usage-data")
+            = link_to icon('question-circle'), help_page_path("user/admin_area/settings/usage_statistics", anchor: "usage-ping")
           .help-block
-            Every week GitLab will report license usage back to GitLab, Inc.
-            Disable this option if you do not want this to occur. To see the
-            JSON payload that will be sent, visit the
-            = succeed '.' do
-              = link_to "Cohorts page", admin_cohorts_path(anchor: 'usage-ping')
+            - if can_be_configured
+              Every week GitLab will report license usage back to GitLab, Inc.
+              Disable this option if you do not want this to occur. To see the
+              JSON payload that will be sent, visit the
+              = succeed '.' do
+                = link_to "Cohorts page", admin_cohorts_path(anchor: 'usage-ping')
+            - else
+              The usage ping is disabled, and cannot be configured through this
+              form. For more information, see the documentation on
+              = succeed '.' do
+                = link_to 'deactivating the usage ping', help_page_path('user/admin_area/settings/usage_statistics', anchor: 'deactivate-the-usage-ping')
 
   %fieldset
     %legend Email

changelogs/unreleased/disable-usage-ping.yml

+---
+title: Allow usage ping to be disabled completely in gitlab.yml
+merge_request:
+author:

config/initializers/1_settings.rb

@@ -241,6 +241,7 @@ Settings.gitlab['domain_whitelist'] ||= []
 Settings.gitlab['import_sources'] ||= %w[github bitbucket gitlab google_code fogbugz git gitlab_project gitea]
 Settings.gitlab['trusted_proxies'] ||= []
 Settings.gitlab['no_todos_messages'] ||= YAML.load_file(Rails.root.join('config', 'no_todos_messages.yml'))
+Settings.gitlab['usage_ping_enabled'] = true if Settings.gitlab['usage_ping_enabled'].nil?
 
 #
 # CI

doc/user/admin_area/settings/usage_statistics.md

@@ -89,6 +89,24 @@ By default, usage ping is opt-out. If you want to deactivate this feature, go to
 the Settings page of your administration panel and uncheck the Usage ping
 checkbox.
 
+To disable the usage ping and prevent it from being configured from the
+administration panel, Omnibus installs can set the following in
+[`gitlab.rb`](https://docs.gitlab.com/omnibus/settings/configuration.html#configuration-options):
+
+```ruby
+gitlab_rails['usage_ping_enabled'] = false
+```
+
+And source installs can set the following in `gitlab.yml`:
+
+```yaml
+production: &base
+  # ...
+  gitlab:
+    # ...
+    usage_ping_enabled: false
+```
+
 ## Privacy policy
 
 GitLab Inc. does **not** collect any sensitive information, like project names

spec/models/application_setting_spec.rb

@@ -211,4 +211,66 @@ describe ApplicationSetting, models: true do
       expect(setting.domain_blacklist).to contain_exactly('example.com', 'test.com', 'foo.bar')
     end
   end
+
+  describe 'usage ping settings' do
+    context 'when the usage ping is disabled in gitlab.yml' do
+      before do
+        allow(Settings.gitlab).to receive(:usage_ping_enabled).and_return(false)
+      end
+
+      it 'does not allow the usage ping to be configured' do
+        expect(setting.usage_ping_can_be_configured?).to be_falsey
+      end
+
+      context 'when the usage ping is disabled in the DB' do
+        before do
+          setting.usage_ping_enabled = false
+        end
+
+        it 'returns false for usage_ping_enabled' do
+          expect(setting.usage_ping_enabled).to be_falsey
+        end
+      end
+
+      context 'when the usage ping is enabled in the DB' do
+        before do
+          setting.usage_ping_enabled = true
+        end
+
+        it 'returns false for usage_ping_enabled' do
+          expect(setting.usage_ping_enabled).to be_falsey
+        end
+      end
+    end
+
+    context 'when the usage ping is enabled in gitlab.yml' do
+      before do
+        allow(Settings.gitlab).to receive(:usage_ping_enabled).and_return(true)
+      end
+
+      it 'allows the usage ping to be configured' do
+        expect(setting.usage_ping_can_be_configured?).to be_truthy
+      end
+
+      context 'when the usage ping is disabled in the DB' do
+        before do
+          setting.usage_ping_enabled = false
+        end
+
+        it 'returns false for usage_ping_enabled' do
+          expect(setting.usage_ping_enabled).to be_falsey
+        end
+      end
+
+      context 'when the usage ping is enabled in the DB' do
+        before do
+          setting.usage_ping_enabled = true
+        end
+
+        it 'returns true for usage_ping_enabled' do
+          expect(setting.usage_ping_enabled).to be_truthy
+        end
+      end
+    end
+  end
 end