client.rb in dapr-0.2.2

- old
+ new

@@ -9,17 +9,19 @@
 module Rubyists
   module Dapr
     # The namespace for the Dapr client
     module Client
       include SemanticLogger::Loggable
-      DAPR_PORT = ENV.fetch('DAPR_GRPC_PORT', '5001')
+      DAPR_PORT = ENV.fetch('DAPR_GRPC_PORT', nil)
       DAPR_URI = ENV.fetch('DAPR_GRPC_HOST', 'localhost')
       DAPR_STUB = ::Dapr::Proto::Runtime::V1::Dapr::Stub
 
-      def self.client
-        logger.info "Creating Dapr client for #{DAPR_URI}:#{DAPR_PORT}"
-        DAPR_STUB.new("#{DAPR_URI}:#{DAPR_PORT}", :this_channel_is_insecure)
+      def self.client(dapr_port: DAPR_PORT, dapr_uri: DAPR_URI)
+        return DummyClient.new if dapr_port.nil?
+
+        logger.info "Creating Dapr client for #{dapr_uri}:#{dapr_port}"
+        DAPR_STUB.new("#{dapr_uri}:#{dapr_port}", :this_channel_is_insecure)
       end
 
       def self.singleton
         @singleton ||= client
       end
@@ -28,9 +30,30 @@
         Rubyists::Dapr::Client.client
       end
 
       def singleton
         @singleton ||= Rubyists::Dapr::Client.singleton
+      end
+
+      # Make a dummy client that responds to every method with a warning and the called method signature
+      class DummyClient
+        include SemanticLogger::Loggable
+
+        def initialize(*_)
+          logger.warn 'Dapr is not available (no DAPR_GRPC_PORT), using dummy client'
+        end
+
+        def method_missing(method_name, *, &)
+          self.class.define_method(method_name) do |*args, &block|
+            logger.warn 'Dapr is not available (no DAPR_GRPC_PORT), using dummy client'
+            { method_name:, args:, block: }
+          end
+          send(method_name, *, &)
+        end
+
+        def respond_to_missing?(_method_name, _include_private = false)
+          true
+        end
       end
     end
   end
 end