perf: expand gateway capacity and prevent receipt replay

gateway/internal/upstream/submit.go

@@ -97,6 +97,12 @@ func (p *connectionPool) submit(
 }
 
 func (c *connection) submitPart(ctx context.Context, cmd queue.SubmitCommand, part submitPart) (uint32, string, queue.SubmitResult, error) {
+	startedAt := time.Now()
+	defer func() {
+		c.mu.Lock()
+		c.lastSubmitRTT = time.Since(startedAt)
+		c.mu.Unlock()
+	}()
 	rspCh := make(chan submitPartResponse, 1)
 	pkt := c.submitRequestPacket(cmd, part)
 
@@ -163,14 +169,20 @@ func (c *connection) submitPart(ctx context.Context, cmd queue.SubmitCommand, pa
 		c.mu.Unlock()
 	}()
 
-	waitCtx, cancel := context.WithTimeout(ctx, defaultSubmitTimeout)
+	timeout := time.Duration(c.config.SubmitTimeoutSeconds) * time.Second
+	if timeout <= 0 {
+		timeout = defaultSubmitTimeout
+	}
+	waitCtx, cancel := context.WithTimeout(ctx, timeout)
 	defer cancel()
 	select {
 	case <-waitCtx.Done():
+		c.markSubmitFailure()
 		result := submitResult(cmd, seq, "", "timeout", "SUBMIT_TIMEOUT", waitCtx.Err().Error())
 		return seq, "", result, waitCtx.Err()
 	case rsp := <-rspCh:
 		if rsp.err != nil {
+			c.markSubmitFailure()
 			result := submitResult(cmd, seq, "", "timeout", "CONNECTION_LOST", rsp.err.Error())
 			return seq, "", result, rsp.err
 		}
@@ -203,6 +215,7 @@ func (c *connection) submitPart(ctx context.Context, cmd queue.SubmitCommand, pa
 			},
 		})
 		if rsp.result == 0 {
+			c.markSubmitSuccess()
 			c.mu.Lock()
 			c.tracker[rsp.msgID] = cmd
 			c.mu.Unlock()
@@ -345,6 +358,12 @@ func validateSubmitCommand(cmd queue.SubmitCommand) error {
 	if cmd.Upstream.Account == "" || cmd.Upstream.PasswordCipher == "" {
 		return fmt.Errorf("upstream account and passwordCipher are required")
 	}
+	if cmd.Upstream.DesiredConnections != 0 && (cmd.Upstream.DesiredConnections < 1 || cmd.Upstream.DesiredConnections > maximumConnections) {
+		return fmt.Errorf("upstream desiredConnections must be between 1 and %d", maximumConnections)
+	}
+	if cmd.Upstream.WindowSize != 0 && (cmd.Upstream.WindowSize < 1 || cmd.Upstream.WindowSize > maximumWindowSize) {
+		return fmt.Errorf("upstream windowSize must be between 1 and %d", maximumWindowSize)
+	}
 	if len(cmd.PhoneNumber) == 0 || len(cmd.Content) == 0 {
 		return fmt.Errorf("phoneNumber and content are required")
 	}