From 793c1098d4774a17eac2399d3ed10d4a2081a8a6 Mon Sep 17 00:00:00 2001
From: Katharina Przybill <30441792+kathap@users.noreply.github.com>
Date: Fri, 5 Jan 2024 10:34:50 +0100
Subject: [PATCH] Introduce config option to disable statsd metrics

This config option allows to send metrics only via prometheus
---
 config/cloud_controller.yml                   |  1 +
 .../config_schemas/base/api_schema.rb         |  1 +
 .../config_schemas/base/clock_schema.rb       |  1 +
 .../base/deployment_updater_schema.rb         |  1 +
 lib/cloud_controller/dependency_locator.rb    | 26 +++++++++++++++++++
 .../deployment_updater/scheduler.rb           |  6 ++++-
 lib/cloud_controller/diego/messenger.rb       |  7 ++++-
 spec/fixtures/config/port_8181_config.yml     |  1 +
 8 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/config/cloud_controller.yml b/config/cloud_controller.yml
index 450568e5b8f..11ddf1b838d 100644
--- a/config/cloud_controller.yml
+++ b/config/cloud_controller.yml
@@ -354,6 +354,7 @@ staging:
 
 statsd_host: "127.0.0.1"
 statsd_port: 8125
+disable_statsd_metrics: false
 
 perform_blob_cleanup: false
 
diff --git a/lib/cloud_controller/config_schemas/base/api_schema.rb b/lib/cloud_controller/config_schemas/base/api_schema.rb
index c6f96d4bf6e..a8bcf59069a 100644
--- a/lib/cloud_controller/config_schemas/base/api_schema.rb
+++ b/lib/cloud_controller/config_schemas/base/api_schema.rb
@@ -322,6 +322,7 @@ class ApiSchema < VCAP::Config
 
             statsd_host: String,
             statsd_port: Integer,
+            optional(:disable_statsd_metrics) => bool,
             system_hostnames: [String],
             default_app_ssh_access: bool,
 
diff --git a/lib/cloud_controller/config_schemas/base/clock_schema.rb b/lib/cloud_controller/config_schemas/base/clock_schema.rb
index 2ddac9017fb..8c6f4d5ec82 100644
--- a/lib/cloud_controller/config_schemas/base/clock_schema.rb
+++ b/lib/cloud_controller/config_schemas/base/clock_schema.rb
@@ -177,6 +177,7 @@ class ClockSchema < VCAP::Config
 
             statsd_host: String,
             statsd_port: Integer,
+            optional(:disable_statsd_metrics) => bool,
 
             max_labels_per_resource: Integer,
             max_annotations_per_resource: Integer,
diff --git a/lib/cloud_controller/config_schemas/base/deployment_updater_schema.rb b/lib/cloud_controller/config_schemas/base/deployment_updater_schema.rb
index 98bb1d0db8d..da1cac6b761 100644
--- a/lib/cloud_controller/config_schemas/base/deployment_updater_schema.rb
+++ b/lib/cloud_controller/config_schemas/base/deployment_updater_schema.rb
@@ -130,6 +130,7 @@ class DeploymentUpdaterSchema < VCAP::Config
 
             statsd_host: String,
             statsd_port: Integer,
+            optional(:disable_statsd_metrics) => bool,
 
             max_labels_per_resource: Integer,
             max_annotations_per_resource: Integer,
diff --git a/lib/cloud_controller/dependency_locator.rb b/lib/cloud_controller/dependency_locator.rb
index 6bb42db847a..6523f652f72 100644
--- a/lib/cloud_controller/dependency_locator.rb
+++ b/lib/cloud_controller/dependency_locator.rb
@@ -441,4 +441,30 @@ def create_paginated_collection_renderer(opts={})
                                                                              })
     end
   end
+
+  class NullDependencyLocator
+    include Singleton
+
+    def config
+      Struct.new
+    end
+
+    def statsd_client
+      @statsd_client ||= NullStatsdClient.new
+    end
+
+    def statsd_updater
+      # Null implementation
+    end
+
+    class NullStatsdClient
+      def timing(_key, _value)
+        # Null implementation
+      end
+
+      def increment(_key)
+        # Null implementation
+      end
+    end
+  end
 end
diff --git a/lib/cloud_controller/deployment_updater/scheduler.rb b/lib/cloud_controller/deployment_updater/scheduler.rb
index c6b2b5a1a5e..f6acc31a36f 100644
--- a/lib/cloud_controller/deployment_updater/scheduler.rb
+++ b/lib/cloud_controller/deployment_updater/scheduler.rb
@@ -9,7 +9,11 @@ class << self
         def start
           with_error_logging('cc.deployment_updater') do
             config = CloudController::DependencyLocator.instance.config
-            statsd_client = CloudController::DependencyLocator.instance.statsd_client
+            if config.get(:disable_statsd_metrics) == false
+              statsd_client = CloudController::DependencyLocator.instance.statsd_client
+            else
+              statsd_client = CloudController::NullDependencyLocator.instance.statsd_client
+            end
 
             update_step = proc {
               update(
diff --git a/lib/cloud_controller/diego/messenger.rb b/lib/cloud_controller/diego/messenger.rb
index 089d1484983..ff95c9606cc 100644
--- a/lib/cloud_controller/diego/messenger.rb
+++ b/lib/cloud_controller/diego/messenger.rb
@@ -58,7 +58,12 @@ def bbs_stager_client
       end
 
       def statsd_updater
-        CloudController::DependencyLocator.instance.statsd_updater
+        config = CloudController::DependencyLocator.instance.config
+        if config.get(:disable_statsd_metrics) == false
+          CloudController::DependencyLocator.instance.statsd_updater
+        else
+          CloudController::NullDependencyLocator.instance.statsd_updater
+        end
       end
 
       def prometheus_updater
diff --git a/spec/fixtures/config/port_8181_config.yml b/spec/fixtures/config/port_8181_config.yml
index ddec9eeea1c..eade372e5ee 100644
--- a/spec/fixtures/config/port_8181_config.yml
+++ b/spec/fixtures/config/port_8181_config.yml
@@ -206,6 +206,7 @@ droplets:
 
 statsd_host: "127.0.0.1"
 statsd_port: 8125
+disable_statsd_metrics: false
 
 perform_blob_cleanup: false