Merge pull request #21 from jxsl13/fix-noop-error-messages

improve error messages that were previously overshadowed by read on closed connection error message due to the connection being closed

snapshot7/storage.go

@@ -17,6 +17,10 @@ const (
 	UninitializedTick = -1
 )
 
+var (
+	ErrNoAltSnapInSnapStorage = errors.New("there is no alt snap in the storage")
+)
+
 // TODO: do we even need this?
 //
 //	can we just put the snap as is in the map?
@@ -85,7 +89,7 @@ func (s *Storage) OldestTick() int {
 
 func (s *Storage) altSnapshot() (*Snapshot, error) {
 	if s.altSnap.snap == nil {
-		return nil, errors.New("there is no alt snap in the storage")
+		return nil, ErrNoAltSnapInSnapStorage
 	}
 	return s.altSnap.snap, nil
 }

teeworlds7/callbacks.go

@@ -25,7 +25,6 @@ func userMsgCallback[T any](userCallbacks []func(T, DefaultAction) error, msg T,
 	if len(userCallbacks) == 0 {
 		if defaultAction != nil {
 			return defaultAction()
-
 		}
 		return nil
 	}

teeworlds7/networking.go

@@ -69,6 +69,19 @@ func (client *Client) Connect(serverIp string, serverPort int) error {
 
 func (client *Client) ConnectContext(ctx context.Context, serverIp string, serverPort int) (err error) {
 	ctx, cancelCause := context.WithCancelCause(ctx)
+	defer cancelCause(nil) // always cancel
+
+	// wait for the reader goroutine to finish execution, before leaving this function scope
+	var wg sync.WaitGroup
+	defer wg.Wait()
+
+	ch := make(chan []byte, maxPacksize)
+	var d net.Dialer
+	conn, err := d.DialContext(ctx, "udp", fmt.Sprintf("%s:%d", serverIp, serverPort))
+	if err != nil {
+		return fmt.Errorf("failed to connect to server: %s:%d: %w", serverIp, serverPort, err)
+	}
+	client.Conn = conn
 	defer func() {
 		// only the first cancelation cause is relevant
 		// subsequent cancelations will be ignored
@@ -86,20 +99,9 @@ func (client *Client) ConnectContext(ctx context.Context, serverIp string, serve
 			err = ctxErr
 			return
 		}
-	}()
 
-	// wait for the reader goroutine to finish execution, before leaving this function scope
-	var wg sync.WaitGroup
-	defer wg.Wait()
-
-	ch := make(chan []byte, maxPacksize)
-	var d net.Dialer
-	conn, err := d.DialContext(ctx, "udp", fmt.Sprintf("%s:%d", serverIp, serverPort))
-	if err != nil {
-		return fmt.Errorf("failed to connect to server: %s:%d: %w", serverIp, serverPort, err)
-	}
-	client.Conn = conn
-	defer func() {
+		// close connection after error handling in order not to
+		// hide the actual cause of the error
 		closeErr := client.Conn.Close()
 		if closeErr != nil {
 			slog.Error("failed to close connection", "error", closeErr)

teeworlds7/system.go

@@ -109,7 +109,10 @@ func (client *Client) processSystem(netMsg messages7.NetMessage, response *proto
 			client.SnapshotStorage.PurgeUntil(deltaTick)
 
 			for _, callback := range client.Callbacks.Snapshot {
-				callback(newFullSnap, nil)
+				err = callback(newFullSnap, noOpFunc)
+				if err != nil {
+					return fmt.Errorf("failed to execute snapshot callback: %w", err)
+				}
 			}
 
 			client.Game.Input.AckGameTick = msg.GameTick
@@ -151,7 +154,10 @@ func (client *Client) processSystem(netMsg messages7.NetMessage, response *proto
 			client.SnapshotStorage.PurgeUntil(deltaTick)
 
 			for _, callback := range client.Callbacks.Snapshot {
-				callback(newFullSnap, nil)
+				err = callback(newFullSnap, noOpFunc)
+				if err != nil {
+					return fmt.Errorf("failed to execute snapshot callback: %w", err)
+				}
 			}
 
 			client.Game.Input.AckGameTick = msg.GameTick
@@ -193,7 +199,7 @@ func (client *Client) processSystem(netMsg messages7.NetMessage, response *proto
 			client.SnapshotStorage.PurgeUntil(deltaTick)
 
 			for _, callback := range client.Callbacks.Snapshot {
-				err = callback(prevSnap, nil)
+				err = callback(prevSnap, noOpFunc)
 				if err != nil {
 					return fmt.Errorf("failed to execute snapshot callback: %w", err)
 				}
@@ -255,3 +261,7 @@ func (client *Client) processSystem(netMsg messages7.NetMessage, response *proto
 	}
 	return true, nil
 }
+
+func noOpFunc() error {
+	return nil
+}