[client,signal,management] Add browser client support (#4415)

util/wsproxy/server/metrics.go

@@ -0,0 +1,118 @@
+package server
+
+import (
+	"context"
+
+	log "github.com/sirupsen/logrus"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
+)
+
+// MetricsRecorder defines the interface for recording proxy metrics
+type MetricsRecorder interface {
+	// RecordConnection records a new connection
+	RecordConnection(ctx context.Context)
+	// RecordDisconnection records a connection closing
+	RecordDisconnection(ctx context.Context)
+	// RecordBytesTransferred records bytes transferred in a direction
+	RecordBytesTransferred(ctx context.Context, direction string, bytes int64)
+	// RecordError records an error
+	RecordError(ctx context.Context, errorType string)
+}
+
+// NoOpMetricsRecorder is a no-op implementation that does nothing
+type NoOpMetricsRecorder struct{}
+
+func (n NoOpMetricsRecorder) RecordConnection(ctx context.Context) {
+	// no-op
+}
+func (n NoOpMetricsRecorder) RecordDisconnection(ctx context.Context) {
+	// no-op
+}
+func (n NoOpMetricsRecorder) RecordBytesTransferred(ctx context.Context, direction string, bytes int64) {
+	// no-op
+}
+func (n NoOpMetricsRecorder) RecordError(ctx context.Context, errorType string) {
+	// no-op
+}
+
+// Recorder implements MetricsRecorder using OpenTelemetry
+type Recorder struct {
+	activeConnections metric.Int64UpDownCounter
+	bytesTransferred  metric.Int64Counter
+	errors            metric.Int64Counter
+}
+
+// NewMetricsRecorder creates a new OpenTelemetry-based metrics recorder
+func NewMetricsRecorder(meter metric.Meter) (*Recorder, error) {
+	activeConnections, err := meter.Int64UpDownCounter(
+		"wsproxy_active_connections",
+		metric.WithDescription("Number of active WebSocket proxy connections"),
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	bytesTransferred, err := meter.Int64Counter(
+		"wsproxy_bytes_transferred_total",
+		metric.WithDescription("Total bytes transferred through the proxy"),
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	errors, err := meter.Int64Counter(
+		"wsproxy_errors_total",
+		metric.WithDescription("Total number of proxy errors"),
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Recorder{
+		activeConnections: activeConnections,
+		bytesTransferred:  bytesTransferred,
+		errors:            errors,
+	}, nil
+}
+
+func (o *Recorder) RecordConnection(ctx context.Context) {
+	o.activeConnections.Add(ctx, 1)
+}
+
+func (o *Recorder) RecordDisconnection(ctx context.Context) {
+	o.activeConnections.Add(ctx, -1)
+}
+
+func (o *Recorder) RecordBytesTransferred(ctx context.Context, direction string, bytes int64) {
+	o.bytesTransferred.Add(ctx, bytes, metric.WithAttributes(
+		attribute.String("direction", direction),
+	))
+}
+
+func (o *Recorder) RecordError(ctx context.Context, errorType string) {
+	o.errors.Add(ctx, 1, metric.WithAttributes(
+		attribute.String("error_type", errorType),
+	))
+}
+
+// Option defines functional options for the Proxy
+type Option func(*Config)
+
+// WithMetrics sets a custom metrics recorder
+func WithMetrics(recorder MetricsRecorder) Option {
+	return func(c *Config) {
+		c.MetricsRecorder = recorder
+	}
+}
+
+// WithOTelMeter creates and sets an OpenTelemetry metrics recorder
+func WithOTelMeter(meter metric.Meter) Option {
+	return func(c *Config) {
+		if recorder, err := NewMetricsRecorder(meter); err == nil {
+			c.MetricsRecorder = recorder
+		} else {
+			log.Warnf("Failed to create OTel metrics recorder: %v", err)
+		}
+	}
+}