move broker to separate file

broker.go

@@ -0,0 +1,85 @@
+package gotelem
+
+import "fmt"
+
+type BrokerRequest struct {
+	Source string // the name of the sender
+	Msg    Frame  // the message to send
+}
+type BrokerClient struct {
+	Name string     // the name of the client
+	Ch   chan Frame // the channel to send frames to this client
+}
+type Broker struct {
+	subs map[string]chan Frame
+
+	publishCh chan BrokerRequest
+
+	subsCh  chan BrokerClient
+	unsubCh chan BrokerClient
+}
+
+func NewBroker(bufsize int) *Broker {
+	b := &Broker{
+		subs:      make(map[string]chan Frame),
+		publishCh: make(chan BrokerRequest, 3),
+		subsCh:    make(chan BrokerClient, 3),
+		unsubCh:   make(chan BrokerClient, 3),
+	}
+	return b
+}
+
+// Start runs the broker and sends messages to the subscribers (but not the sender)
+func (b *Broker) Start() {
+
+	for {
+		select {
+		case newClient := <-b.subsCh:
+			b.subs[newClient.Name] = newClient.Ch
+		case req := <-b.publishCh:
+			for name, ch := range b.subs {
+				if name == req.Source {
+					continue // don't send to ourselves.
+				}
+				// a kinda-inelegant non-blocking push.
+				// if we can't do it, we just drop it. this should ideally never happen.
+				select {
+				case ch <- req.Msg:
+				default:
+					fmt.Printf("we dropped a packet to dest %s", name)
+				}
+			}
+		case clientToRemove := <-b.unsubCh:
+			close(b.subs[clientToRemove.Name])
+			delete(b.subs, clientToRemove.Name)
+		}
+	}
+}
+
+func (b *Broker) Publish(name string, msg Frame) {
+	breq := BrokerRequest{
+		Source: name,
+		Msg:    msg,
+	}
+	b.publishCh <- breq
+}
+
+func (b *Broker) Subscribe(name string) <-chan Frame {
+	ch := make(chan Frame, 3)
+
+	bc := BrokerClient{
+		Name: name,
+		Ch:   ch,
+	}
+	b.subsCh <- bc
+	return ch
+}
+
+func (b *Broker) Unsubscribe(name string) {
+	bc := BrokerClient{
+		Name: name,
+	}
+	b.unsubCh <- bc
+}
+
+// TODO: don't use channels for everything to avoid using a mutex

cmd/gotelem/cli/server.go

@@ -5,13 +5,11 @@ import (
 	"net"
 	"time"
 
-	"github.com/kschamplin/gotelem/can"
+	"github.com/kschamplin/gotelem"
 	"github.com/kschamplin/gotelem/socketcan"
 	"github.com/urfave/cli/v2"
 )
 
-const xbeeCategory = "XBee settings"
-
 var serveCmd = &cli.Command{
 	Name:    "serve",
 	Aliases: []string{"server", "s"},
@@ -27,7 +25,7 @@ var serveCmd = &cli.Command{
 
 func serve(useXbee bool) {
 
-	broker := NewBroker(3)
+	broker := gotelem.NewBroker(3)
 	// start the can listener
 	go vcanTest()
 	go canHandler(broker)
@@ -47,22 +45,22 @@ func serve(useXbee bool) {
 	}
 }
 
-func handleCon(conn net.Conn, broker *Broker) {
+func handleCon(conn net.Conn, broker *gotelem.Broker) {
 	//	reader := msgp.NewReader(conn)
 
 	conn.Close()
 }
 
-func xbeeSvc(b *Broker) {
+func xbeeSvc(b *gotelem.Broker) {
 
 }
 
 // this spins up a new can socket on vcan0 and broadcasts a packet every second. for testing.
 func vcanTest() {
 	sock, _ := socketcan.NewCanSocket("vcan0")
-	testFrame := &can.Frame{
+	testFrame := &gotelem.Frame{
 		Id:   0x234,
-		Kind: can.SFF,
+		Kind: gotelem.CanSFFFrame,
 		Data: []byte{0, 1, 2, 3, 4, 5, 6, 7},
 	}
 	for {
@@ -73,12 +71,12 @@ func vcanTest() {
 	}
 }
 
-func canHandler(broker *Broker) {
+func canHandler(broker *gotelem.Broker) {
 	rxCh := broker.Subscribe("socketcan")
 	sock, _ := socketcan.NewCanSocket("vcan0")
 
 	// start a simple dispatcher that just relays can frames.
-	rxCan := make(chan can.Frame)
+	rxCan := make(chan gotelem.Frame)
 	go func() {
 		for {
 			pkt, _ := sock.Recv()
@@ -95,82 +93,3 @@ func canHandler(broker *Broker) {
 		}
 	}
 }
-
-type BrokerRequest struct {
-	Source string    // the name of the sender
-	Msg    can.Frame // the message to send
-}
-type BrokerClient struct {
-	Name string         // the name of the client
-	Ch   chan can.Frame // the channel to send frames to this client
-}
-type Broker struct {
-	subs map[string]chan can.Frame
-
-	publishCh chan BrokerRequest
-
-	subsCh  chan BrokerClient
-	unsubCh chan BrokerClient
-}
-
-func NewBroker(bufsize int) *Broker {
-	b := &Broker{
-		subs:      make(map[string]chan can.Frame),
-		publishCh: make(chan BrokerRequest, 3),
-		subsCh:    make(chan BrokerClient, 3),
-		unsubCh:   make(chan BrokerClient, 3),
-	}
-	return b
-}
-
-func (b *Broker) Start() {
-
-	for {
-		select {
-		case newClient := <-b.subsCh:
-			b.subs[newClient.Name] = newClient.Ch
-		case req := <-b.publishCh:
-			for name, ch := range b.subs {
-				if name == req.Source {
-					continue // don't send to ourselves.
-				}
-				// a kinda-inelegant non-blocking push.
-				// if we can't do it, we just drop it. this should ideally never happen.
-				select {
-				case ch <- req.Msg:
-				default:
-					fmt.Printf("we dropped a packet to dest %s", name)
-				}
-			}
-		case clientToRemove := <-b.unsubCh:
-			close(b.subs[clientToRemove.Name])
-			delete(b.subs, clientToRemove.Name)
-		}
-	}
-}
-
-func (b *Broker) Publish(name string, msg can.Frame) {
-	breq := BrokerRequest{
-		Source: name,
-		Msg:    msg,
-	}
-	b.publishCh <- breq
-}
-
-func (b *Broker) Subscribe(name string) <-chan can.Frame {
-	ch := make(chan can.Frame, 3)
-
-	bc := BrokerClient{
-		Name: name,
-		Ch:   ch,
-	}
-	b.subsCh <- bc
-	return ch
-}
-
-func (b *Broker) Unsubscribe(name string) {
-	bc := BrokerClient{
-		Name: name,
-	}
-	b.unsubCh <- bc
-}