initial http reader for messages

configuration_flags.go

@@ -23,6 +23,8 @@ type Configuration struct {
 	SocketFolder string
 	// TCP Listener for sending messages to the system
 	TCPListener string
+	// HTTP Listener for sending messages to the system
+	HTTPListener string
 	// The folder where the database should live
 	DatabaseFolder string
 	// some unique string to identify this Edge unit
@@ -90,6 +92,7 @@ type ConfigurationFromFile struct {
 	ConfigFolder               *string
 	SocketFolder               *string
 	TCPListener                *string
+	HTTPListener               *string
 	DatabaseFolder             *string
 	NodeName                   *string
 	BrokerAddress              *string
@@ -132,6 +135,7 @@ func newConfigurationDefaults() Configuration {
 		ConfigFolder:             "./etc/",
 		SocketFolder:             "./tmp",
 		TCPListener:              "",
+		HTTPListener:             "",
 		DatabaseFolder:           "./var/lib",
 		BrokerAddress:            "127.0.0.1:4222",
 		NatsConnectRetryInterval: 10,
@@ -185,6 +189,11 @@ func checkConfigValues(cf ConfigurationFromFile) Configuration {
 	} else {
 		conf.TCPListener = *cf.TCPListener
 	}
+	if cf.HTTPListener == nil {
+		conf.HTTPListener = cd.HTTPListener
+	} else {
+		conf.HTTPListener = *cf.HTTPListener
+	}
 	if cf.DatabaseFolder == nil {
 		conf.DatabaseFolder = cd.DatabaseFolder
 	} else {
@@ -360,6 +369,7 @@ func (c *Configuration) CheckFlags() error {
 	//flag.StringVar(&c.ConfigFolder, "configFolder", fc.ConfigFolder, "Defaults to ./usr/local/steward/etc/. *NB* This flag is not used, if your config file are located somwhere else than default set the location in an env variable named CONFIGFOLDER")
 	flag.StringVar(&c.SocketFolder, "socketFolder", fc.SocketFolder, "folder who contains the socket file. Defaults to ./tmp/. If other folder is used this flag must be specified at startup.")
 	flag.StringVar(&c.TCPListener, "tcpListener", fc.TCPListener, "start up a TCP listener in addition to the Unix Socket, to give messages to the system. e.g. localhost:8888. No value means not to start the listener, which is default. NB: You probably don't want to start this on any other interface than localhost")
+	flag.StringVar(&c.HTTPListener, "httpListener", fc.HTTPListener, "start up a HTTP listener in addition to the Unix Socket, to give messages to the system. e.g. localhost:8888. No value means not to start the listener, which is default. NB: You probably don't want to start this on any other interface than localhost")
 	flag.StringVar(&c.DatabaseFolder, "databaseFolder", fc.DatabaseFolder, "folder who contains the database file. Defaults to ./var/lib/. If other folder is used this flag must be specified at startup.")
 	flag.StringVar(&c.NodeName, "nodeName", fc.NodeName, "some unique string to identify this Edge unit")
 	flag.StringVar(&c.BrokerAddress, "brokerAddress", fc.BrokerAddress, "the address of the message broker")

read_socket_or_tcp_listener.go

@@ -7,7 +7,10 @@ import (
 	"io"
 	"log"
 	"net"
+	"net/http"
 	"os"
+
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 // readSocket will read the .sock file specified.
@@ -137,6 +140,36 @@ func (s *server) writeStewSocket(toStewSocketCh []byte) {
 	//s.StewSockListener
 }
 
+func (s *server) readHTTPlistenerHandler(w http.ResponseWriter, r *http.Request) {
+	b, err := io.ReadAll(r.Body)
+	if err != nil {
+		er := fmt.Errorf("error: readHTTPListenerHandler: %v", err)
+		sendErrorLogMessage(s.configuration, s.metrics, s.newMessagesCh, Node(s.nodeName), er)
+	}
+	r.Body.Close()
+
+	log.Printf("got: %v\n", string(b))
+
+}
+
+func (s *server) readHttpListener() {
+	go func() {
+		n, err := net.Listen("tcp", s.configuration.HTTPListener)
+		if err != nil {
+			log.Printf("error: startMetrics: failed to open prometheus listen port: %v\n", err)
+			os.Exit(1)
+		}
+		mux := http.NewServeMux()
+		mux.Handle("/metrics", promhttp.Handler())
+
+		err = http.Serve(n, mux)
+		if err != nil {
+			log.Printf("error: startMetrics: failed to start http.Serve: %v\n", err)
+			os.Exit(1)
+		}
+	}()
+}
+
 // The subject are made up of different parts of the message field.
 // To make things easier and to avoid figuring out what the subject
 // is in all places we've created the concept of subjectAndMessage

server.go

@@ -214,11 +214,16 @@ func (s *server) Start() {
 	// Start the checking the input socket for new messages from operator.
 	go s.readSocket()
 
-	// Check if we should start the tcp listener fro new messages from operator.
+	// Check if we should start the tcp listener for new messages from operator.
 	if s.configuration.TCPListener != "" {
 		go s.readTCPListener()
 	}
 
+	// Check if we should start the http listener for new messages from operator.
+	if s.configuration.HTTPListener != "" {
+		go s.readHttpListener()
+	}
+
 	// Start up the predefined subscribers.
 	//
 	// Since all the logic to handle processes are tied to the process