src/lib.go: WIP impl Ping

1 files changed, 48 insertions, 7 deletions

diff --git a/src/lib.go b/src/lib.go
index 2bcb98c..6aee989 100644
--- a/src/lib.go
+++ b/src/lib.go
@@ -41,23 +41,35 @@ const pingFrequency  = time.Duration(30) * time.Second
 const pongMaxLatency = time.Duration(5)  * time.Second
 
 
-
+// type UUID string
+	
 type Channel struct {
 }
 
-type Context struct {
-	db *sql.DB
-	tx chan int
-}
-
 type Connection struct {
 	conn            net.Conn
 	replyChan       chan string
+	lastReadFrom    time.Time
+	lastWrittenTo   time.Time
 	// id              *UUID
 	id              string
 	isAuthenticated bool
 }
 
+type User struct {
+	connections []Connection
+}
+
+type State struct {
+	users map[string]*User
+}
+
+type Context struct {
+	db *sql.DB
+	state State
+	tx chan int
+}
+
 type MessageParams struct {
 	Middle   []string
 	Trailing string
@@ -247,6 +259,8 @@ func ActionFnFor(command string) func(*Context, Message) {
 }
 
 func ProcessMessage(ctx *Context, connection *Connection, rawMessage string) {
+	connection.lastReadFrom = time.Now()
+
 	msg, err := ParseMessage(rawMessage)
 	if err != nil {
 		g.Info(
@@ -295,22 +309,49 @@ func WriteLoop(ctx *Context, connection *Connection) {
 			EmitWriteToClientError()
 			continue
 		}
+
+		connection.lastWrittenTo = time.Now()
 	}
 
 	EmitActiveConnection.Dec()
 	connection.conn.Close()
 }
 
+func Kill(ctx *Context, connection *Connection) {
+	// lock?
+	delete(ctx.state.users, connection.id)
+	// unlock?
+	close(connection.replyChan)
+	connection.conn.Close() // Ignore errors?
+}
+
+const PingWindow = 30 * time.Second
 func PingLoop(ctx *Context, connection *Connection) {
-	// fmt.Println("PingLoop")
+	for {
+		time.Sleep(PingWindow)
+		if (time.Since(connection.lastReadFrom) <= PingWindow) {
+			continue
+		}
+
+		if ((connection.lastWrittenTo.Sub(connection.lastReadFrom)) <= PingWindow) {
+			connection.replyChan <- "PING"
+			continue
+		}
+
+		Kill(ctx, connection)
+		break
+	}
 }
 
 func HandleConnection(ctx *Context, conn net.Conn) {
 	EmitActiveConnection.Inc()
 	// FIXME: WaitGroup here?
+	now := time.Now()
 	connection := Connection {
 		conn: conn,
 		isAuthenticated: false,
+		lastReadFrom:  now,
+		lastWrittenTo: now,
 	}
 	go  ReadLoop(ctx, &connection)
 	go WriteLoop(ctx, &connection)