add observer

observer/plugin/grpc.go

@@ -0,0 +1,98 @@
+package observer
+
+import (
+	"context"
+	"io"
+
+	"github.com/go-gost/core/logger"
+	"github.com/go-gost/core/observer"
+	"github.com/go-gost/plugin/observer/proto"
+	"github.com/go-gost/x/internal/plugin"
+	"github.com/go-gost/x/service"
+	"github.com/go-gost/x/stats"
+	"google.golang.org/grpc"
+)
+
+type grpcPlugin struct {
+	conn   grpc.ClientConnInterface
+	client proto.ObserverClient
+	log    logger.Logger
+}
+
+// NewGRPCPlugin creates an Observer plugin based on gRPC.
+func NewGRPCPlugin(name string, addr string, opts ...plugin.Option) observer.Observer {
+	var options plugin.Options
+	for _, opt := range opts {
+		opt(&options)
+	}
+
+	log := logger.Default().WithFields(map[string]any{
+		"kind":     "observer",
+		"observer": name,
+	})
+	conn, err := plugin.NewGRPCConn(addr, &options)
+	if err != nil {
+		log.Error(err)
+	}
+
+	p := &grpcPlugin{
+		conn: conn,
+		log:  log,
+	}
+	if conn != nil {
+		p.client = proto.NewObserverClient(conn)
+	}
+	return p
+}
+
+func (p *grpcPlugin) Observe(ctx context.Context, events []observer.Event, opts ...observer.Option) error {
+	if p.client == nil || len(events) == 0 {
+		return nil
+	}
+
+	var req proto.ObserveRequest
+
+	for _, event := range events {
+		switch event.Type() {
+		case observer.EventStatus:
+			ev := event.(service.ServiceEvent)
+			req.Events = append(req.Events, &proto.Event{
+				Kind:    ev.Kind,
+				Service: ev.Service,
+				Type:    string(event.Type()),
+				Status: &proto.ServiceStatus{
+					State: string(ev.State),
+					Msg:   ev.Msg,
+				},
+			})
+		case observer.EventStats:
+			ev := event.(stats.StatsEvent)
+			req.Events = append(req.Events, &proto.Event{
+				Kind:    ev.Kind,
+				Service: ev.Service,
+				Client:  ev.Client,
+				Type:    string(event.Type()),
+				Stats: &proto.Stats{
+					TotalConns:   ev.TotalConns,
+					CurrentConns: ev.CurrentConns,
+					InputBytes:   ev.InputBytes,
+					OutputBytes:  ev.OutputBytes,
+					TotalErrs:    ev.TotalErrs,
+				},
+			})
+		}
+	}
+	_, err := p.client.Observe(ctx, &req)
+	if err != nil {
+		p.log.Error(err)
+		return err
+	}
+	return nil
+}
+
+func (p *grpcPlugin) Close() error {
+	if closer, ok := p.conn.(io.Closer); ok {
+		return closer.Close()
+	}
+	return nil
+}