Customize data sent

README.md

@@ -45,8 +45,6 @@ These will be converted to issues in the future, but some other ideas...
 Test that connectivity is NOT made between different machines that should not
 talk to each other, for firewall/security reasons.
 
-Customizable data to send.
-
 Allow metric collection (Prometheus, etc).
 
 Realtime streaming updates for the HTML view.

cmd/cyn/cmds/root.go

@@ -22,6 +22,7 @@ var config struct {
 	SendUDP      []string      `mapstructure:"send-udp"`
 	SendTCP      []string      `mapstructure:"send-tcp"`
 	SendInterval time.Duration `mapstructure:"send-interval"`
+	SendData     string        `mapstructure:"send-data"`
 	HTTPServer   struct {
 		Address string `mapstructure:"address"`
 	} `mapstructure:"http"`
@@ -49,6 +50,7 @@ func init() {
 	flags.StringSliceP("listen-tcp", "t", nil, "An IP:port address to listen on for TCP.  Can be specified multiple times.")
 	flags.StringSliceP("send-udp", "U", nil, "An IP:port address to send to (UDP).  Can be specified multiple times.")
 	flags.StringSliceP("send-tcp", "T", nil, "An IP:port address to send to (TCP).  Can be specified multiple times.")
+	flags.StringP("send-data", "d", "hi", "The string data to send.")
 	flags.DurationP("send-interval", "i", time.Second, "How long to wait between attempting to send data")
 	flags.String("http.address", "", "An address:port to host an HTTP server on for realtime data, such as '127.0.0.1:8080'")
 	flags.Bool("sinks.stdout.enabled", false, "Whether to enable the stdout metrics sink")
@@ -124,7 +126,7 @@ var rootCmd = &cobra.Command{
 				return fmt.Errorf("net.ResolveUDPAddr for %q: %w", sendUDPTo, err)
 			}
 
-			instance.AddUDPSender(sender.NewUDPSender(*addr, config.SendInterval, sink))
+			instance.AddUDPSender(sender.NewUDPSender(*addr, config.SendInterval, sink, []byte(config.SendData)))
 		}
 
 		// We could probably generalize this a bit better, but it's short enough
@@ -136,7 +138,7 @@ var rootCmd = &cobra.Command{
 				return fmt.Errorf("net.ResolveTCPAddr for %q: %w", sendTCPTo, err)
 			}
 
-			instance.AddTCPSender(sender.NewTCPSender(*addr, config.SendInterval, sink))
+			instance.AddTCPSender(sender.NewTCPSender(*addr, config.SendInterval, sink, []byte(config.SendData)))
 		}
 
 		return instance.Run()

pkg/sender/tcp.go

@@ -18,14 +18,17 @@ type TCPSender struct {
 	conn          *net.TCPConn
 	sendInterval  time.Duration
 
+	sendData []byte
+
 	sink metrics.Sink
 }
 
-func NewTCPSender(addr net.TCPAddr, sendInterval time.Duration, sink metrics.Sink) *TCPSender {
+func NewTCPSender(addr net.TCPAddr, sendInterval time.Duration, sink metrics.Sink, sendData []byte) *TCPSender {
 	return &TCPSender{
 		broadcastAddr: addr,
 		sendInterval:  sendInterval,
 		sink:          sink,
+		sendData:      sendData,
 	}
 }
 
@@ -91,7 +94,7 @@ func (s *TCPSender) Run() error {
 	s.mu.RUnlock()
 
 	for {
-		err := s.Send([]byte("hi"))
+		err := s.Send(s.sendData)
 
 		if err != nil {
 			log.Printf("Failed to send to %q: %v", sendTCPTo, err)

pkg/sender/udp.go

@@ -21,14 +21,17 @@ type UDPSender struct {
 	fromAddr string
 	toAddr   string
 
+	sendData []byte
+
 	sink metrics.Sink
 }
 
-func NewUDPSender(addr net.UDPAddr, sendInterval time.Duration, sink metrics.Sink) *UDPSender {
+func NewUDPSender(addr net.UDPAddr, sendInterval time.Duration, sink metrics.Sink, sendData []byte) *UDPSender {
 	return &UDPSender{
 		broadcastAddr: addr,
 		sendInterval:  sendInterval,
 		sink:          sink,
+		sendData:      sendData,
 	}
 }
 
@@ -80,7 +83,7 @@ func (s *UDPSender) Run() error {
 	s.mu.RUnlock()
 
 	for {
-		err := s.Send([]byte("hi"))
+		err := s.Send(s.sendData)
 		if err != nil {
 			log.Printf("Failed to send to %q: %v", sendUDPTo, err)
 		}

tests/features/udp.feature

@@ -10,9 +10,9 @@ Feature: send and receive UDP
 
   Scenario: one listen one send (shorthand flags)
     Given I run cyn -u 127.0.0.1:14563
-    And I run cyn -U 127.0.0.1:14563 -i 10ms
+    And I run cyn -U 127.0.0.1:14563 -i 10ms -d "bdd-test-data"
     When I wait a moment
-    Then the stdout contains "hi"
+    Then the stdout contains "bdd-test-data"
 
   Scenario: an instance is set to call itself via config file
     Given a configuration file that contains: