more traces

pkg/proxy/remotehost.go

@@ -10,6 +10,9 @@ import (
 	"time"
 
 	messages "git.tornberg.me/go-cart-actor/pkg/messages"
+	"go.opentelemetry.io/contrib/bridges/otelslog"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
 )
@@ -26,6 +29,14 @@ type RemoteHost struct {
 	missedPings   int
 }
 
+const name = "proxy"
+
+var (
+	tracer = otel.Tracer(name)
+	meter  = otel.Meter(name)
+	logger = otelslog.NewLogger(name)
+)
+
 func NewRemoteHost(host string) (*RemoteHost, error) {
 
 	target := fmt.Sprintf("%s:1337", host)
@@ -147,8 +158,20 @@ func (h *RemoteHost) Proxy(id uint64, w http.ResponseWriter, r *http.Request) (b
 	target := fmt.Sprintf("%s%s", h.httpBase, r.URL.RequestURI())
 
 	log.Printf("proxy target: %s, method: %s", target, r.Method)
-	req, err := http.NewRequestWithContext(r.Context(), r.Method, target, r.Body)
+
+	ctx, span := tracer.Start(r.Context(), "remote_proxy")
+	defer span.End()
+	span.SetAttributes(
+		attribute.String("cartid", fmt.Sprintf("%d", id)),
+		attribute.String("host", h.host),
+		attribute.String("method", r.Method),
+		attribute.String("target", target),
+	)
+	logger.InfoContext(ctx, "proxying request", "cartid", id, "host", h.host, "method", r.Method)
+
+	req, err := http.NewRequestWithContext(ctx, r.Method, target, r.Body)
 	if err != nil {
+		span.RecordError(err)
 		http.Error(w, "proxy build error", http.StatusBadGateway)
 		return false, err
 	}
@@ -162,10 +185,12 @@ func (h *RemoteHost) Proxy(id uint64, w http.ResponseWriter, r *http.Request) (b
 	}
 	res, err := h.client.Do(req)
 	if err != nil {
+		span.RecordError(err)
 		http.Error(w, "proxy request error", http.StatusBadGateway)
 		return false, err
 	}
 	defer res.Body.Close()
+	span.SetAttributes(attribute.Int("status_code", res.StatusCode))
 	for k, v := range res.Header {
 		for _, vv := range v {
 			w.Header().Add(k, vv)
@@ -176,6 +201,7 @@ func (h *RemoteHost) Proxy(id uint64, w http.ResponseWriter, r *http.Request) (b
 	w.WriteHeader(res.StatusCode)
 	_, copyErr := io.Copy(w, res.Body)
 	if copyErr != nil {
+		span.RecordError(copyErr)
 		return true, copyErr
 	}
 	return true, nil