fix linter

opencensus/hlf/hlf.go

@@ -0,0 +1,106 @@
+package hlf
+
+import (
+	"context"
+	"errors"
+
+	"go.opencensus.io/plugin/ocgrpc"
+	"go.opencensus.io/trace"
+	"google.golang.org/grpc/stats"
+)
+
+// Wrap easy way for plug-up grpc.StatsHandler and mixing needed annotations to span
+func Wrap(statsHandler *ocgrpc.ClientHandler) stats.Handler {
+	return &wrapper{
+		oc: statsHandler,
+	}
+}
+
+type wrapper struct {
+	oc *ocgrpc.ClientHandler
+}
+
+func (w *wrapper) TagConn(ctx context.Context, connInfo *stats.ConnTagInfo) context.Context {
+	if w.oc != nil {
+		return w.oc.TagConn(ctx, connInfo)
+	}
+
+	return ctx
+}
+
+func (w *wrapper) HandleConn(ctx context.Context, cs stats.ConnStats) {
+	if w.oc != nil {
+		w.oc.HandleConn(ctx, cs)
+	}
+}
+
+func (w *wrapper) TagRPC(ctx context.Context, rpcInfo *stats.RPCTagInfo) context.Context {
+	if w.oc != nil {
+		return w.oc.TagRPC(ctx, rpcInfo)
+	}
+	return ctx
+}
+
+func (w *wrapper) HandleRPC(ctx context.Context, rs stats.RPCStats) {
+	span := trace.FromContext(ctx)
+
+	switch rs := rs.(type) {
+	case *stats.InHeader:
+		if rs.RemoteAddr != nil {
+			span.AddAttributes(
+				trace.StringAttribute(
+					"InHeader.RemoteAddr",
+					rs.RemoteAddr.String(),
+				),
+			)
+		}
+		if rs.LocalAddr != nil {
+			span.AddAttributes(
+				trace.StringAttribute(
+					"InHeader.LocalAddr",
+					rs.LocalAddr.String(),
+				),
+			)
+		}
+
+		span.AddAttributes(
+			trace.StringAttribute(
+				"InHeader.Compression",
+				rs.Compression,
+			),
+		)
+	case *stats.OutHeader:
+		if rs.RemoteAddr != nil {
+			span.AddAttributes(
+				trace.StringAttribute(
+					"OutHeader.RemoteAddr",
+					rs.RemoteAddr.String(),
+				),
+			)
+		}
+		if rs.LocalAddr != nil {
+			span.AddAttributes(
+				trace.StringAttribute(
+					"OutHeader.LocalAddr",
+					rs.LocalAddr.String(),
+				),
+			)
+		}
+
+		span.AddAttributes(
+			trace.StringAttribute(
+				"OutHeader.Compression",
+				rs.Compression,
+			),
+		)
+	}
+	// sometimes we get cancelled context if further execution(asking peers etc.) isn't necessary
+	// but request is fully valid, and we don't want to see confusing errors in jaeger
+	if errors.Is(ctx.Err(), context.Canceled) {
+		return
+	}
+
+	if w.oc != nil {
+		w.oc.HandleRPC(ctx, rs)
+	}
+}