Add remote configuration worker

lib/datadog/core/remote/worker.rb

@@ -0,0 +1,79 @@
+# frozen_string_literal: true
+
+module Datadog
+  module Core
+    module Remote
+      class Worker
+        def initialize(interval:, &block)
+          @mutex = Mutex.new
+          @thr = nil
+
+          @starting = false
+          @stopping = false
+          @started = false
+
+          @interval = interval
+          @block = block
+        end
+
+        def start
+          Datadog.logger.debug { 'remote worker starting' }
+
+          @mutex.lock
+
+          return if @starting || @started
+
+          @starting = true
+
+          @thr = Thread.new { poll(@interval) }
+
+          @started = true
+          @starting = false
+
+          Datadog.logger.debug { 'remote worker started' }
+        ensure
+          @mutex.unlock
+        end
+
+        def stop
+          Datadog.logger.debug { 'remote worker stopping' }
+
+          @mutex.lock
+
+          @stopping = true
+
+          @thr.kill unless @thr.nil?
+
+          @started = false
+          @stopping = false
+
+          Datadog.logger.debug { 'remote worker stopped' }
+        ensure
+          @mutex.unlock
+        end
+
+        def started?
+          @started
+        end
+
+        private
+
+        def poll(interval)
+          loop do
+            break unless @mutex.synchronize { @starting || @started }
+
+            call
+
+            sleep(interval)
+          end
+        end
+
+        def call
+          Datadog.logger.debug { 'remote worker perform' }
+
+          @block.call
+        end
+      end
+    end
+  end
+end