fix: missing dot between header attributes (#2)

* fix: missing dot between header attributes
* follow semconv compliance

Author: hgiasac

middleware.go

@@ -8,7 +8,6 @@ import (
 	"net/http"
 	"runtime/debug"
 	"slices"
-	"strconv"
 	"strings"
 	"time"
 
@@ -17,6 +16,7 @@ import (
 	"go.opentelemetry.io/otel/codes"
 	"go.opentelemetry.io/otel/metric"
 	"go.opentelemetry.io/otel/propagation"
+	semconv "go.opentelemetry.io/otel/semconv/v1.37.0"
 	"go.opentelemetry.io/otel/trace"
 )
 
@@ -102,41 +102,31 @@ func (tm *tracingMiddleware) ServeHTTP( //nolint:gocognit,cyclop,funlen,maintidx
 	ctx := r.Context()
 	span := trace.SpanFromContext(ctx)
 
-	hostName, rawPort, _ := strings.Cut(r.Host, ":")
-	port := 80
+	urlScheme := r.URL.Scheme
+	if urlScheme == "" {
+		urlScheme = "http"
+	}
 
-	if rawPort != "" {
-		p, err := strconv.Atoi(rawPort)
-		if err == nil {
-			port = p
-		}
-	} else if strings.HasPrefix(r.URL.Scheme, "https") {
+	hostName, port, _ := SplitHostPort(r.Host)
+
+	switch {
+	case port > 0:
+	case urlScheme == "https":
 		port = 443
+	default:
+		port = 80
 	}
 
 	metricAttrs := []attribute.KeyValue{
-		attribute.String("http.request.method", r.Method),
-		attribute.String("url.scheme", r.URL.Scheme),
-		attribute.String("server.address", hostName),
-		attribute.Int("server.port", port),
+		{
+			Key:   semconv.HTTPRequestMethodKey,
+			Value: attribute.StringValue(r.Method),
+		},
+		semconv.URLScheme(urlScheme),
+		semconv.ServerAddress(hostName),
+		semconv.ServerPort(port),
+		semconv.ClientAddress(r.RemoteAddr),
 	}
-	requestPathAttr := attribute.String("http.request.path", r.URL.Path)
-
-	if !tm.Options.HighCardinalityMetricDisabled {
-		metricAttrs = append(metricAttrs, requestPathAttr)
-	}
-
-	activeRequestsAttrSet := metric.WithAttributeSet(attribute.NewSet(metricAttrs...))
-
-	tm.ActiveRequestsMetric.Add(ctx, 1, activeRequestsAttrSet)
-
-	metricAttrs = append(
-		metricAttrs,
-		attribute.String(
-			"network.protocol.version",
-			fmt.Sprintf("%d.%d", r.ProtoMajor, r.ProtoMinor),
-		),
-	)
 
 	if !slices.Contains(tm.Options.DebugPaths, strings.ToLower(r.URL.Path)) {
 		ctx, span = tm.Exporters.Tracer.Start(
@@ -157,7 +147,37 @@ func (tm *tracingMiddleware) ServeHTTP( //nolint:gocognit,cyclop,funlen,maintidx
 	// Add HTTP semantic attributes to the server span
 	// See: https://opentelemetry.io/docs/specs/semconv/http/http-spans/#http-server-semantic-conventions
 	span.SetAttributes(metricAttrs...)
-	span.SetAttributes(requestPathAttr)
+
+	if !tm.Options.HighCardinalityMetricDisabled {
+		metricAttrs = append(metricAttrs, attribute.String("http.request.path", r.URL.Path))
+	}
+
+	activeRequestsAttrSet := metric.WithAttributeSet(attribute.NewSet(metricAttrs...))
+
+	tm.ActiveRequestsMetric.Add(ctx, 1, activeRequestsAttrSet)
+
+	protocolAttr := semconv.NetworkProtocolVersion(fmt.Sprintf("%d.%d", r.ProtoMajor, r.ProtoMinor))
+
+	metricAttrs = append(
+		metricAttrs,
+		protocolAttr,
+	)
+
+	span.SetAttributes(
+		protocolAttr,
+		semconv.URLFull(r.URL.String()),
+		semconv.UserAgentOriginal(r.UserAgent()),
+	)
+
+	peer, peerPort, _ := SplitHostPort(r.RemoteAddr)
+
+	if peer != "" {
+		span.SetAttributes(semconv.NetworkPeerAddress(peer))
+
+		if peerPort > 0 {
+			span.SetAttributes(semconv.NetworkPeerPort(peerPort))
+		}
+	}
 
 	requestBodySize := r.ContentLength
 	requestLogHeaders := NewTelemetryHeaders(r.Header, tm.Options.AllowedRequestHeaders...)
@@ -198,12 +218,10 @@ func (tm *tracingMiddleware) ServeHTTP( //nolint:gocognit,cyclop,funlen,maintidx
 			activeRequestsAttrSet,
 		)
 
-		statusCodeAttr := attribute.Int(
-			"http.response.status_code",
-			statusCode,
-		)
-		latency := time.Since(start).Seconds()
+		statusCodeAttr := semconv.HTTPResponseStatusCode(statusCode)
+		span.SetAttributes(statusCodeAttr)
 
+		latency := time.Since(start).Seconds()
 		responseLogData["status"] = statusCode
 
 		logAttrs := []any{
@@ -215,7 +233,7 @@ func (tm *tracingMiddleware) ServeHTTP( //nolint:gocognit,cyclop,funlen,maintidx
 		if err != nil {
 			stack := string(debug.Stack())
 			logAttrs = append(logAttrs, slog.Any("error", err), slog.String("stacktrace", stack))
-			span.SetAttributes(statusCodeAttr, attribute.String("stacktrace", stack))
+			span.SetAttributes(semconv.ExceptionStacktrace(stack))
 		}
 
 		metricAttrs = append(metricAttrs, statusCodeAttr)
@@ -265,7 +283,7 @@ func (tm *tracingMiddleware) ServeHTTP( //nolint:gocognit,cyclop,funlen,maintidx
 
 	if requestBodySize > 0 {
 		requestLogData["size"] = requestBodySize
-		span.SetAttributes(attribute.Int64("http.request.body.size", requestBodySize))
+		span.SetAttributes(semconv.HTTPRequestBodySize(int(requestBodySize)))
 	}
 
 	defer func() {
@@ -284,9 +302,9 @@ func (tm *tracingMiddleware) ServeHTTP( //nolint:gocognit,cyclop,funlen,maintidx
 
 			errBytes, jsonErr := json.Marshal(err)
 			if jsonErr != nil {
-				span.SetAttributes(attribute.String("error", fmt.Sprintf("%v", err)))
+				span.SetAttributes(attribute.String("exception.error", fmt.Sprintf("%v", err)))
 			} else {
-				span.SetAttributes(attribute.String("error", string(errBytes)))
+				span.SetAttributes(attribute.String("exception.error", string(errBytes)))
 			}
 		}
 	}()
@@ -300,7 +318,7 @@ func (tm *tracingMiddleware) ServeHTTP( //nolint:gocognit,cyclop,funlen,maintidx
 	responseLogData["size"] = ww.BytesWritten()
 	responseLogData["headers"] = responseLogHeaders
 
-	span.SetAttributes(attribute.Int("http.response.body.size", ww.BytesWritten()))
+	span.SetAttributes(semconv.HTTPResponseBodySize(ww.BytesWritten()))
 	SetSpanHeaderAttributes(span, "http.response.header", responseLogHeaders)
 
 	// skip printing very large responses.

utils.go

@@ -3,12 +3,15 @@ package gotel
 import (
 	"bytes"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"log/slog"
+	"net"
 	"net/http"
 	"regexp"
 	"slices"
+	"strconv"
 	"strings"
 
 	"github.com/google/uuid"
@@ -23,6 +26,21 @@ const (
 	contentTypeHeader = "Content-Type"
 )
 
+var excludedSpanHeaderAttributes = map[string]bool{
+	"baggage":           true,
+	"traceparent":       true,
+	"traceresponse":     true,
+	"tracestate":        true,
+	"x-b3-sampled":      true,
+	"x-b3-spanid":       true,
+	"x-b3-traceid":      true,
+	"x-b3-parentspanid": true,
+	"x-b3-flags":        true,
+	"b3":                true,
+}
+
+var errInvalidHostPort = errors.New("invalid host port")
+
 // SetSpanHeaderAttributes sets header attributes to the otel span.
 func SetSpanHeaderAttributes(
 	span trace.Span,
@@ -33,8 +51,13 @@ func SetSpanHeaderAttributes(
 	allowedHeadersLength := len(allowedHeaders)
 
 	for key, values := range headers {
-		if allowedHeadersLength == 0 || slices.Contains(allowedHeaders, strings.ToLower(key)) {
-			span.SetAttributes(attribute.StringSlice(prefix+strings.ToLower(key), values))
+		lowerKey := strings.ToLower(key)
+
+		if (allowedHeadersLength == 0 && !excludedSpanHeaderAttributes[lowerKey]) ||
+			(allowedHeadersLength > 0 && slices.Contains(allowedHeaders, lowerKey)) {
+			span.SetAttributes(
+				attribute.StringSlice(fmt.Sprintf("%s.%s", prefix, lowerKey), values),
+			)
 		}
 	}
 }
@@ -95,10 +118,51 @@ func MaskString(input string) string {
 	case inputLength < 12:
 		return input[0:1] + strings.Repeat("*", inputLength-1)
 	default:
-		return input[0:3] + strings.Repeat("*", 7) + fmt.Sprintf("(%d)", inputLength)
+		return input[0:2] + strings.Repeat("*", 8) + fmt.Sprintf("(%d)", inputLength)
 	}
 }
 
+// SplitHostPort splits a network address hostport of the form "host",
+// "host%zone", "[host]", "[host%zone]", "host:port", "host%zone:port",
+// "[host]:port", "[host%zone]:port", or ":port" into host or host%zone and
+// port.
+//
+// An empty host is returned if it is not provided or unparsable. A negative
+// port is returned if it is not provided or unparsable.
+func SplitHostPort(hostport string) (string, int, error) {
+	port := -1
+
+	if strings.HasPrefix(hostport, "[") {
+		addrEnd := strings.LastIndex(hostport, "]")
+		if addrEnd < 0 {
+			// Invalid hostport.
+			return "", port, errInvalidHostPort
+		}
+
+		if i := strings.LastIndex(hostport[addrEnd:], ":"); i < 0 {
+			host := hostport[1:addrEnd]
+
+			return host, port, nil
+		}
+	} else {
+		if i := strings.LastIndex(hostport, ":"); i < 0 {
+			return hostport, port, nil
+		}
+	}
+
+	host, pStr, err := net.SplitHostPort(hostport)
+	if err != nil {
+		return host, port, err
+	}
+
+	p, err := strconv.ParseUint(pStr, 10, 16)
+	if err != nil {
+		return "", port, err
+	}
+
+	return host, int(p), err
+}
+
 // returns the value or default one if value is empty.
 func getDefault[T comparable](value T, defaultValue T) T {
 	var empty T

utils_test.go

@@ -26,7 +26,7 @@ func TestNewTelemetryHeaders(t *testing.T) {
 			},
 			Expected: http.Header{
 				"Content-Type":  []string{"application/json"},
-				"Authorization": []string{"Bea*******(65)"},
+				"Authorization": []string{"Be********(65)"},
 				"Api-Key":       []string{"******"},
 				"Secret-Key":    []string{"s*********"},
 			},