Fix failing go checks

Author: silvanocerza

discovery_server.go renamed to discovery.go

@@ -15,7 +15,7 @@
 // a commercial license, send an email to [email protected].
 //
 
-// discovery is a library for handling the Arduino Pluggable-Discovery protocol
+// Package discovery is a library for handling the Arduino Pluggable-Discovery protocol
 // (https://github.com/arduino/tooling-rfcs/blob/main/RFCs/0002-pluggable-discovery.md#pluggable-discovery-api-via-stdinstdout)
 //
 // The library implements the state machine and the parsing logic to communicate with a pluggable-discovery client.
@@ -81,9 +81,9 @@ type EventCallback func(event string, port *Port)
 // performs a STOP+START_SYNC cycle.
 type ErrorCallback func(err string)
 
-// A DiscoveryServer is a pluggable discovery protocol handler,
-// it must be created using the NewDiscoveryServer function.
-type DiscoveryServer struct {
+// A Server is a pluggable discovery protocol handler,
+// it must be created using the NewServer function.
+type Server struct {
 	impl               Discovery
 	outputChan         chan *message
 	userAgent          string
@@ -95,11 +95,11 @@ type DiscoveryServer struct {
 	cachedErr          string
 }
 
-// NewDiscoveryServer creates a new discovery server backed by the
+// NewServer creates a new discovery server backed by the
 // provided pluggable discovery implementation. To start the server
 // use the Run method.
-func NewDiscoveryServer(impl Discovery) *DiscoveryServer {
-	return &DiscoveryServer{
+func NewServer(impl Discovery) *Server {
+	return &Server{
 		impl:       impl,
 		outputChan: make(chan *message),
 	}
@@ -110,7 +110,7 @@ func NewDiscoveryServer(impl Discovery) *DiscoveryServer {
 // The function blocks until the `QUIT` command is received or
 // the input stream is closed. In case of IO error the error is
 // returned.
-func (d *DiscoveryServer) Run(in io.Reader, out io.Writer) error {
+func (d *Server) Run(in io.Reader, out io.Writer) error {
 	go d.outputProcessor(out)
 	defer close(d.outputChan)
 	reader := bufio.NewReader(in)
@@ -150,7 +150,7 @@ func (d *DiscoveryServer) Run(in io.Reader, out io.Writer) error {
 	}
 }
 
-func (d *DiscoveryServer) hello(cmd string) {
+func (d *Server) hello(cmd string) {
 	if d.initialized {
 		d.outputChan <- messageError("hello", "HELLO already called")
 		return
@@ -162,12 +162,12 @@ func (d *DiscoveryServer) hello(cmd string) {
 		return
 	}
 	d.userAgent = matches[2]
-	if v, err := strconv.ParseInt(matches[1], 10, 64); err != nil {
+	v, err := strconv.ParseInt(matches[1], 10, 64)
+	if err != nil {
 		d.outputChan <- messageError("hello", "Invalid protocol version: "+matches[2])
 		return
-	} else {
-		d.reqProtocolVersion = int(v)
 	}
+	d.reqProtocolVersion = int(v)
 	if err := d.impl.Hello(d.userAgent, 1); err != nil {
 		d.outputChan <- messageError("hello", err.Error())
 		return
@@ -180,7 +180,7 @@ func (d *DiscoveryServer) hello(cmd string) {
 	d.initialized = true
 }
 
-func (d *DiscoveryServer) start() {
+func (d *Server) start() {
 	if d.started {
 		d.outputChan <- messageError("start", "Discovery already STARTed")
 		return
@@ -199,7 +199,7 @@ func (d *DiscoveryServer) start() {
 	d.outputChan <- messageOk("start")
 }
 
-func (d *DiscoveryServer) eventCallback(event string, port *Port) {
+func (d *Server) eventCallback(event string, port *Port) {
 	id := port.Address + "|" + port.Protocol
 	if event == "add" {
 		d.cachedPorts[id] = port
@@ -209,11 +209,11 @@ func (d *DiscoveryServer) eventCallback(event string, port *Port) {
 	}
 }
 
-func (d *DiscoveryServer) errorCallback(msg string) {
+func (d *Server) errorCallback(msg string) {
 	d.cachedErr = msg
 }
 
-func (d *DiscoveryServer) list() {
+func (d *Server) list() {
 	if !d.started {
 		d.outputChan <- messageError("list", "Discovery not STARTed")
 		return
@@ -236,7 +236,7 @@ func (d *DiscoveryServer) list() {
 	}
 }
 
-func (d *DiscoveryServer) startSync() {
+func (d *Server) startSync() {
 	if d.syncStarted {
 		d.outputChan <- messageError("start_sync", "Discovery already START_SYNCed")
 		return
@@ -253,7 +253,7 @@ func (d *DiscoveryServer) startSync() {
 	d.outputChan <- messageOk("start_sync")
 }
 
-func (d *DiscoveryServer) stop() {
+func (d *Server) stop() {
 	if !d.syncStarted && !d.started {
 		d.outputChan <- messageError("stop", "Discovery already STOPped")
 		return
@@ -269,18 +269,18 @@ func (d *DiscoveryServer) stop() {
 	d.outputChan <- messageOk("stop")
 }
 
-func (d *DiscoveryServer) syncEvent(event string, port *Port) {
+func (d *Server) syncEvent(event string, port *Port) {
 	d.outputChan <- &message{
 		EventType: event,
 		Port:      port,
 	}
 }
 
-func (d *DiscoveryServer) errorEvent(msg string) {
+func (d *Server) errorEvent(msg string) {
 	d.outputChan <- messageError("start_sync", msg)
 }
 
-func (d *DiscoveryServer) outputProcessor(outWriter io.Writer) {
+func (d *Server) outputProcessor(outWriter io.Writer) {
 	// Start go routine to serialize messages printing
 	go func() {
 		for msg := range d.outputChan {

dummy-discovery/args/args.go

@@ -28,7 +28,8 @@ var Tag = "snapshot"
 // Timestamp is the current timestamp
 var Timestamp = "unknown"
 
-func ParseArgs() {
+// Parse arguments passed by the user
+func Parse() {
 	for _, arg := range os.Args[1:] {
 		if arg == "" {
 			continue

dummy-discovery/main.go

@@ -28,35 +28,49 @@ import (
 	"github.com/arduino/pluggable-discovery-protocol-handler/dummy-discovery/args"
 )
 
-type DummyDiscovery struct {
+// dummyDiscovery is an example implementation of a Discovery.
+// It simulates a real implementation of a Discovery by generating
+// connected ports deterministically, it can also be used for testing
+// purposes.
+type dummyDiscovery struct {
 	startSyncCount int
 	closeChan      chan<- bool
 }
 
 func main() {
-	args.ParseArgs()
-	dummyDiscovery := &DummyDiscovery{}
-	server := discovery.NewDiscoveryServer(dummyDiscovery)
+	args.Parse()
+	dummy := &dummyDiscovery{}
+	server := discovery.NewServer(dummy)
 	if err := server.Run(os.Stdin, os.Stdout); err != nil {
 		os.Exit(1)
 	}
 }
 
-func (d *DummyDiscovery) Hello(userAgent string, protocol int) error {
+// Hello does nothing.
+// In a real implementation it could setup background processes
+// or other kind of resources necessary to discover Ports.
+func (d *dummyDiscovery) Hello(userAgent string, protocol int) error {
 	return nil
 }
 
-func (d *DummyDiscovery) Quit() {}
+// Quit does nothing.
+// In a real implementation it can be used to tear down resources
+// used to discovery Ports.
+func (d *dummyDiscovery) Quit() {}
 
-func (d *DummyDiscovery) Stop() error {
+// Stop is used to stop the goroutine started by StartSync
+// used to discover ports.
+func (d *dummyDiscovery) Stop() error {
 	if d.closeChan != nil {
 		d.closeChan <- true
+		close(d.closeChan)
 		d.closeChan = nil
 	}
 	return nil
 }
 
-func (d *DummyDiscovery) StartSync(eventCB discovery.EventCallback, errorCB discovery.ErrorCallback) error {
+// StartSync starts the goroutine that generates fake Ports.
+func (d *dummyDiscovery) StartSync(eventCB discovery.EventCallback, errorCB discovery.ErrorCallback) error {
 	d.startSyncCount++
 	if d.startSyncCount%5 == 0 {
 		return errors.New("could not start_sync every 5 times")
@@ -70,8 +84,8 @@ func (d *DummyDiscovery) StartSync(eventCB discovery.EventCallback, errorCB disc
 		var closeChan <-chan bool = c
 
 		// Output initial port state
-		eventCB("add", CreateDummyPort())
-		eventCB("add", CreateDummyPort())
+		eventCB("add", createDummyPort())
+		eventCB("add", createDummyPort())
 
 		// Start sending events
 		count := 0
@@ -84,7 +98,7 @@ func (d *DummyDiscovery) StartSync(eventCB discovery.EventCallback, errorCB disc
 			case <-time.After(2 * time.Second):
 			}
 
-			port := CreateDummyPort()
+			port := createDummyPort()
 			eventCB("add", port)
 
 			select {
@@ -108,7 +122,8 @@ func (d *DummyDiscovery) StartSync(eventCB discovery.EventCallback, errorCB disc
 
 var dummyCounter = 0
 
-func CreateDummyPort() *discovery.Port {
+// createDummyPort creates a Port with fake data
+func createDummyPort() *discovery.Port {
 	dummyCounter++
 	return &discovery.Port{
 		Address:       fmt.Sprintf("%d", dummyCounter),