Add topic getter to message class

Author: rwstauner

ext/bindings/message.cpp

@@ -41,6 +41,7 @@ Message::Message(const std::string& data, Rice::Object arg = Rice::Object()) {
   }
 
   _msg = mb.build();
+  built = true;
 }
 
 Rice::String Message::getData() {
@@ -65,6 +66,12 @@ Rice::String Message::getOrderingKey() {
   return to_ruby(_msg.getOrderingKey());
 }
 
+Rice::Object Message::getTopicName() {
+  // If the message topic hasn't been set (it gets set when received, not when
+  // built) getTopicName will try to dereference a null pointer.
+  return built ? Rice::Nil : to_ruby(_msg.getTopicName());
+}
+
 }
 
 using namespace Rice;
@@ -84,5 +91,6 @@ void bind_message(Module& module) {
     .define_method("properties", &pulsar_rb::Message::getProperties)
     .define_method("partition_key", &pulsar_rb::Message::getPartitionKey)
     .define_method("ordering_key", &pulsar_rb::Message::getOrderingKey)
+    .define_method("topic", &pulsar_rb::Message::getTopicName)
     ;
 }

ext/bindings/message.hpp

@@ -21,6 +21,7 @@ namespace pulsar_rb {
   class Message {
   public:
     pulsar::Message _msg;
+    bool built = false; // built with builder rather than returned from c++
     Message(const pulsar::Message& msg) : _msg(msg) {};
     Message(const std::string& data, Rice::Object opts);
 
@@ -29,6 +30,7 @@ namespace pulsar_rb {
     Rice::Hash getProperties();
     Rice::String getPartitionKey();
     Rice::String getOrderingKey();
+    Rice::Object getTopicName();
 
     typedef Rice::Data_Object<Message> ptr;
   };

spec/pulsar/client_spec.rb

@@ -43,9 +43,12 @@
 
     it "can consume a single topic" do
       consumer = client.subscribe(topic, subscription_name)
-      t = Thread.new { consumer.receive(timeout_ms).data }
+      t = Thread.new { consumer.receive(timeout_ms) }
       client.create_producer(topic).send("single")
-      expect(t.join.value).to eq("single")
+      message = t.join.value
+
+      expect(message.data).to eq("single")
+      expect(message.topic).to eq(topic)
     end
 
     it "can consume multiple topics" do

spec/pulsar/message_spec.rb

@@ -24,6 +24,13 @@
       expect(m.data).to eq("payload")
     end
 
+    describe "topic" do
+      it "is nil when built rather than received" do
+        m = described_class.new("payload")
+        expect(m.topic).to be_nil
+      end
+    end
+
     describe "properties" do
       it "takes properties" do
         m = described_class.new("payload", properties: {"a" => "1", "b" => "2"})