Add store for saving current proto descriptor file set

Author: davalpargal

clients/ruby/lib/stencil.rb

@@ -2,9 +2,11 @@
 require_relative "stencil/configuration"
 require_relative "stencil/constants"
 require_relative "stencil/client"
+require_relative "stencil/store"
 
 require "http"
-require "concurrent"
+require "concurrent/timer_task"
+require "concurrent/mutable_struct"
 require "protobuf"
 
 module Stencil

clients/ruby/lib/stencil/client.rb

@@ -5,14 +5,18 @@ def initialize
       begin
         @config = Stencil.configuration
         validate_configuration(@config)
-        @root = nil
+
         setup_http_client
+
+        @store = Store.new
         load_descriptors
+        setup_store_update_job
       end
     end
 
     def get_type(proto_name)
-      @root.file.each do |file_desc|
+      file_descriptor_set = @store.read(@config.registry_url)
+      file_descriptor_set.file.each do |file_desc|
         file_desc.message_type.each do |message|
           if proto_name == "#{file_desc.options.java_package}.#{message.name}"
             return message
@@ -22,6 +26,10 @@ def get_type(proto_name)
       raise InvalidProtoClass.new
     end
 
+    def close
+      @task.shutdown
+    end
+
     private
 
     def validate_configuration(configuration)
@@ -42,7 +50,16 @@ def load_descriptors
         raise HTTPClientError.new(e.message)
       end
 
-      @root = Google::Protobuf::FileDescriptorSet.decode(response.body)
+      file_descriptor_set = Google::Protobuf::FileDescriptorSet.decode(response.body)
+      @store.write(@config.registry_url, file_descriptor_set)
+    end
+
+    def setup_store_update_job
+      begin
+        @task = Concurrent::TimerTask.new(execution_interval: @config.refresh_ttl_in_secs) do
+          load_descriptors
+        end
+      end
     end
   end
 end

clients/ruby/lib/stencil/store.rb

@@ -0,0 +1,18 @@
+module Stencil
+  class Store
+    def initialize
+      @lock = Concurrent::ReadWriteLock.new
+      @data = Hash.new
+    end
+
+    def write(key, value)
+      @lock.with_write_lock do
+        @data.store(key, value)
+      end
+    end
+
+    def read(key)
+      @data[key]
+    end
+  end
+end

clients/ruby/spec/stencil/store_spec.rb

@@ -0,0 +1,30 @@
+module Stencil
+  RSpec.describe Store do
+    context "#read" do
+      let(:sample_key) { "sample_key" }
+      let(:sample_value) { 123 }
+
+      it "should be able to handle concurrent reads of data" do
+        store = Store.new
+        store.write(sample_key, sample_value)
+
+        5.times do
+          Thread.start do
+            expect(store.read(sample_key)).to eq(sample_value)
+          end
+        end
+      end
+    end
+
+    context "#write" do
+      let(:sample_key) { "sample_key" }
+      let(:sample_value) { 100 }
+
+      it "should be able to handle concurrent writes of data by locking data" do
+        store = Store.new
+        store.write(sample_key, sample_value)
+        expect(store.read(sample_key)).to eq(sample_value)
+      end
+    end
+  end
+end