Changed to upercase const values for command and events, and added choosing of prometheus port

README.md

@@ -81,20 +81,20 @@ Subject naming are case sensitive, and can not contain the space are the tab cha
 
 Nodename: Are the hostname of the device. This do not have to be resolvable via DNS, it is just a unique name for the host to receive the message.
 
-Command/Event: Are type of message sent. `command` or `event`. Description of the differences are mentioned earlier.\
+Command/Event: Are type of message sent. `CommandACK`/`EventACK`/`CommandNACK`/`EventNACK`. Description of the differences are mentioned earlier.\
 Info: The command/event which is called a MessageType are present in both the Subject structure and the Message structure. The reason for this is that it is used both in the naming of a subject, and in the message for knowing what kind of message it is and how to handle it.
 
-Method: Are the functionality the message provide. Example could be `shellcommand` or `syslogforwarding`
+Method: Are the functionality the message provide. Example could be `Shellcommand` or `Syslogforwarding`
 
 ##### Complete subject example
 
 For syslog of type event to a host named "ship1"
 
-`ship1.event.syslogforwarding`
+`ship1.EventACK.Syslogforwarding`
 
 and for a shell command of type command to a host named "ship2"
 
-`ship2.command.shellcommand`
+`ship2.CommandACK.Shellcommand`
 
 ## TODO
 
@@ -146,6 +146,8 @@ One the nodes out there
 
 `./steward --node="ship1"` & `./steward --node="ship1"` and so on.
 
+Use the `--help` flag to get all possibilities.
+
 ### Sending messages with commands or events
 
 Right now there are to types of messages.
@@ -169,8 +171,8 @@ Example JSON for pasting a message of type command into the `inmsg.txt` file
         
         "toNode": "ship1",
         "data": ["bash","-c","ls -l ../"],
-        "commandOrEvent":"commandACK",
-        "method":"shellCommand"
+        "commandOrEvent":"CommandACK",
+        "method":"ShellCommand"
             
     }
 ]
@@ -184,16 +186,16 @@ To send specify more messages at once do
         
         "toNode": "ship1",
         "data": ["bash","-c","ls -l ../"],
-        "commandOrEvent":"commandACK",
-        "method":"shellCommand"
+        "commandOrEvent":"CommandACK",
+        "method":"ShellCommand"
             
     },
     {
         
         "toNode": "ship2",
         "data": ["bash","-c","ls -l ../"],
-        "commandOrEvent":"commandACK",
-        "method":"shellCommand"
+        "commandOrEvent":"CommandACK",
+        "method":"ShellCommand"
             
     }
 ]
@@ -212,8 +214,8 @@ The content of `inmsg.txt` will be erased as messages a processed.
     {
         "toNode": "central",
         "data": ["some message sent from a ship for testing\n"],
-        "commandOrEvent":"eventACK",
-        "method":"textLogging"
+        "commandOrEvent":"EventACK",
+        "method":"TextLogging"
     }
 ]
 ```

cmd/main.go

@@ -15,6 +15,7 @@ func main() {
 	nodeName := flag.String("node", "0", "some unique string to identify this Edge unit")
 	brokerAddress := flag.String("brokerAddress", "0", "the address of the message broker")
 	profilingPort := flag.String("profilingPort", "", "The number of the profiling port")
+	promHostAndPort := flag.String("promHostAndPort", ":2112", "host and port for prometheus listener, e.g. localhost:2112")
 	//isCentral := flag.Bool("isCentral", false, "used to indicate that this is the central master that will subscribe to error message subjects")
 	flag.Parse()
 
@@ -27,7 +28,7 @@ func main() {
 
 	}
 
-	s, err := steward.NewServer(*brokerAddress, *nodeName)
+	s, err := steward.NewServer(*brokerAddress, *nodeName, *promHostAndPort)
 	if err != nil {
 		log.Printf("error: failed to connect to broker: %v\n", err)
 		os.Exit(1)

commandOrEventType.go

@@ -41,17 +41,17 @@ const (
 	// delivered back in the reply ack message.
 	// The message should contain the unique ID of the
 	// command.
-	CommandACK CommandOrEvent = "commandACK"
+	CommandACK CommandOrEvent = "CommandACK"
 	// Same as above, but No ACK.
-	CommandNACK CommandOrEvent = "commandNACK"
+	CommandNACK CommandOrEvent = "CommandNACK"
 	// Same as above, but No ACK
 	// Event, wait for and return the ACK message. This means
 	// that the command should be executed immediately
 	// and that we should get the confirmation if it
 	// was successful or not.
-	EventACK CommandOrEvent = "eventACK"
+	EventACK CommandOrEvent = "EventACK"
 	// Same as above, but No ACK.
-	EventNACK CommandOrEvent = "eventNACK"
+	EventNACK CommandOrEvent = "EventNACK"
 	// eventCommand, just wait for the ACK that the
 	// message is received. What action happens on the
 	// receiving side is up to the received to decide.

example/orig.json

@@ -1,30 +0,0 @@
-[
-    {
-        "subject":
-            {
-                "node":"ship1",
-                "messageType":"command",
-                "method":"shellcommand",
-                "domain":"shell"
-            },
-        "message":
-            {
-                "data": ["bash","-c","uname -a"],
-                "messageType":"Command"
-            }
-    },
-    {
-        "subject":
-            {
-                "node":"ship2",
-                "messageType":"command",
-                "method":"shellcommand",
-                "domain":"shell"
-            },
-        "message":
-            {
-                "data": ["bash","-c","uname -a"],
-                "messageType":"Command"
-            }
-    }
-]

example/toCentral-sayHello.json

@@ -2,7 +2,7 @@
     {
         "toNode": "central",
         "data": [""],
-        "commandOrEvent":"eventNACK",
-        "method":"sayHello"
+        "commandOrEvent":"EventNACK",
+        "method":"SayHello"
     }
 ]

example/toCentral.json

@@ -2,7 +2,7 @@
     {
         "toNode": "central",
         "data": ["some message sent from a ship for testing\n"],
-        "commandOrEvent":"eventACK",
-        "method":"textLogging"
+        "commandOrEvent":"EventACK",
+        "method":"TextLogging"
     }
 ]

example/toShip1.json

@@ -3,8 +3,8 @@
         
         "toNode": "ship1",
         "data": ["bash","-c","netstat -an|grep -i listen"],
-        "commandOrEvent":"commandACK",
-        "method":"shellCommand"
+        "commandOrEvent":"CommandACK",
+        "method":"ShellCommand"
             
     }
 ]

example/toShip1and2.json

@@ -2,8 +2,8 @@
     {
         "toNode": "*",
         "data": ["bash","-c","tree ../"],
-        "commandOrEvent":"commandACK",
-        "method":"shellCommand"
+        "commandOrEvent":"CommandACK",
+        "method":"ShellCommand"
 
     }
 ]

example/toShip2.json

@@ -2,8 +2,8 @@
     {
         "toNode": "ship2",
         "data": ["bash","-c","tree ../"],
-        "commandOrEvent":"commandACK",
-        "method":"shellCommand"
+        "commandOrEvent":"CommandACK",
+        "method":"ShellCommand"
 
     }
 ]

prometheus.go

@@ -2,6 +2,8 @@ package steward
 
 import (
 	"fmt"
+	"log"
+	"net"
 	"net/http"
 
 	"github.com/prometheus/client_golang/prometheus"
@@ -19,14 +21,17 @@ type metrics struct {
 	sayHelloNodes map[node]struct{}
 	// The channel to pass metrics that should be processed
 	metricsCh chan metricType
+	// host and port where prometheus metrics will be exported
+	hostAndPort string
 }
 
 // HERE:
-func newMetrics() *metrics {
+func newMetrics(hostAndPort string) *metrics {
 	m := metrics{
 		sayHelloNodes: make(map[node]struct{}),
 	}
 	m.metricsCh = make(chan metricType)
+	m.hostAndPort = hostAndPort
 
 	return &m
 }
@@ -100,6 +105,13 @@ func (s *server) startMetrics() {
 		}
 	}()
 
-	http.Handle("/metrics", promhttp.Handler())
-	http.ListenAndServe(":2112", nil)
+	//http.Handle("/metrics", promhttp.Handler())
+	//http.ListenAndServe(":2112", nil)
+	n, err := net.Listen("tcp", s.metrics.hostAndPort)
+	if err != nil {
+		log.Printf("error: failed to open prometheus listen port: %v\n", err)
+	}
+	m := http.NewServeMux()
+	m.Handle("/metrics", promhttp.Handler())
+	http.Serve(n, m)
 }

publisher.go

@@ -64,7 +64,7 @@ type server struct {
 }
 
 // newServer will prepare and return a server type
-func NewServer(brokerAddress string, nodeName string) (*server, error) {
+func NewServer(brokerAddress string, nodeName string, promHostAndPort string) (*server, error) {
 	conn, err := nats.Connect(brokerAddress, nil)
 	if err != nil {
 		log.Printf("error: nats.Connect failed: %v\n", err)
@@ -82,7 +82,7 @@ func NewServer(brokerAddress string, nodeName string) (*server, error) {
 		logCh:                   make(chan []byte),
 		methodsAvailable:        m.GetMethodsAvailable(),
 		commandOrEventAvailable: co.GetCommandOrEventAvailable(),
-		metrics:                 newMetrics(),
+		metrics:                 newMetrics(promHostAndPort),
 	}
 
 	return s, nil
@@ -112,7 +112,7 @@ func (s *server) Start() {
 	// Start a subscriber for shellCommand messages
 	{
 		fmt.Printf("Starting shellCommand subscriber: %#v\n", s.nodeName)
-		sub := newSubject("shellCommand", CommandACK, s.nodeName)
+		sub := newSubject(ShellCommand, CommandACK, s.nodeName)
 		proc := s.processPrepareNew(sub, s.errorCh, processKindSubscriber)
 		// fmt.Printf("*** %#v\n", proc)
 		go s.processSpawnWorker(proc)
@@ -121,16 +121,16 @@ func (s *server) Start() {
 	// Start a subscriber for textLogging messages
 	{
 		fmt.Printf("Starting textlogging subscriber: %#v\n", s.nodeName)
-		sub := newSubject("textLogging", EventACK, s.nodeName)
+		sub := newSubject(TextLogging, EventACK, s.nodeName)
 		proc := s.processPrepareNew(sub, s.errorCh, processKindSubscriber)
 		// fmt.Printf("*** %#v\n", proc)
 		go s.processSpawnWorker(proc)
 	}
 
-	// Start a subscriber for sayHello messages
+	// Start a subscriber for SayHello messages
 	{
-		fmt.Printf("Starting sayHello subscriber: %#v\n", s.nodeName)
-		sub := newSubject("sayHello", EventNACK, s.nodeName)
+		fmt.Printf("Starting SayHello subscriber: %#v\n", s.nodeName)
+		sub := newSubject(SayHello, EventNACK, s.nodeName)
 		proc := s.processPrepareNew(sub, s.errorCh, processKindSubscriber)
 		// fmt.Printf("*** %#v\n", proc)
 		go s.processSpawnWorker(proc)

subscriberMethodTypes.go

@@ -34,11 +34,11 @@ func (m Method) GetMethodsAvailable() MethodsAvailable {
 
 const (
 	// Shell command to be executed via f.ex. bash
-	ShellCommand Method = "shellCommand"
+	ShellCommand Method = "ShellCommand"
 	// Send text logging to some host
-	TextLogging Method = "textLogging"
+	TextLogging Method = "TextLogging"
 	// Send Hello I'm here message
-	SayHello Method = "sayHello"
+	SayHello Method = "SayHello"
 )
 
 type MethodsAvailable struct {