initial relay request types

.gitignore

@@ -13,3 +13,4 @@ ships/
 .gitignore
 testing_messages/
 test.file
+doc/concept/via/README.md

message_and_subject.go

@@ -77,11 +77,13 @@ type Message struct {
 	// initial request message.
 	PreviousMessage *Message
 
-	// The node to send the message via.
-	viaTo Node
-	// The node where the via message originated, and where we want
-	// to send the end result.
-	viaFrom Node
+	// The node to relay the message via.
+	RelayViaNode Node
+	// The node where the relayed message originated, and where we want
+	// to send back the end result.
+	RelayFromNode Node
+	// The original value of the ToNode field of the original message.
+	RelayToNode Node
 
 	// done is used to signal when a message is fully processed.
 	// This is used for signaling back to the ringbuffer that we are

requests.go

@@ -120,6 +120,8 @@ const (
 	REQTailFile Method = "REQTailFile"
 	// Write to steward socket
 	REQToSocket Method = "REQToSocket"
+	// Send a message via a node
+	REQRelay Method = "REQRelay"
 )
 
 // The mapping of all the method constants specified, what type
@@ -187,6 +189,9 @@ func (m Method) GetMethodsAvailable() MethodsAvailable {
 			REQToSocket: methodREQToSocket{
 				commandOrEvent: EventACK,
 			},
+			REQRelay: methodREQRelay{
+				commandOrEvent: EventACK,
+			},
 		},
 	}
 
@@ -1525,3 +1530,22 @@ func (m methodREQToSocket) handler(proc process, message Message, node string) (
 }
 
 // ----
+
+type methodREQRelay struct {
+	commandOrEvent CommandOrEvent
+}
+
+func (m methodREQRelay) getKind() CommandOrEvent {
+	return m.commandOrEvent
+}
+
+// Handler to relay messages via a host.
+func (m methodREQRelay) handler(proc process, message Message, node string) ([]byte, error) {
+	// relay the message here to the actual host here.
+
+	// Send back an ACK message.
+	ackMsg := []byte("confirmed from: " + node + ": " + fmt.Sprint(message.ID))
+	return ackMsg, nil
+}
+
+// ----

server.go

@@ -437,16 +437,18 @@ func (s *server) routeMessagesToProcess(dbFileName string) {
 						proc = existingProc
 					}
 
+					// HERE ?
+					// We've got'n the message from the ringbuffer, and now found the
+					// process to send it on.
+					// NB: Think we should swap the ToNode field here with the value
+					// in RelayNode ???
+
 					// We have found the process to route the message to, deliver it.
 					proc.subject.messageCh <- m
 
-					// If no process to handle the specific subject exist,
-					// the we create and spawn one.
-
 					break
 				} else {
-					// If a publisher process do not exist for the given subject, create it, and
-					// by using the goto at the end redo the process for this specific message.
+					// If a publisher process do not exist for the given subject, create it.
 					log.Printf("info: processNewMessages: did not find that specific subject, starting new process for subject: %v\n", subjName)
 
 					sub := newSubject(sam.Subject.Method, sam.Subject.ToNode)
@@ -455,7 +457,7 @@ func (s *server) routeMessagesToProcess(dbFileName string) {
 					proc.spawnWorker(s.processes, s.natsConn)
 					log.Printf("info: processNewMessages: new process started, subject: %v, processID: %v\n", subjName, proc.processID)
 
-					// Now when the process is spawned we jump back to the redo: label,
+					// Now when the process is spawned we continue,
 					// and send the message to that new process.
 					continue
 				}