Add OpenTelemetryHook

internal/util.go

@@ -2,7 +2,10 @@ package internal
 
 import (
 	"context"
+	"fmt"
+	"strconv"
 	"time"
+	"unicode/utf8"
 
 	"github.com/go-redis/redis/v8/internal/util"
 	"go.opentelemetry.io/otel/api/global"
@@ -69,3 +72,74 @@ func WithSpan(ctx context.Context, name string, fn func(context.Context) error)
 
 	return fn(ctx)
 }
+
+func AppendArg(b []byte, v interface{}) []byte {
+	switch v := v.(type) {
+	case nil:
+		return append(b, "<nil>"...)
+	case string:
+		return appendUTF8String(b, v)
+	case []byte:
+		return appendUTF8String(b, String(v))
+	case int:
+		return strconv.AppendInt(b, int64(v), 10)
+	case int8:
+		return strconv.AppendInt(b, int64(v), 10)
+	case int16:
+		return strconv.AppendInt(b, int64(v), 10)
+	case int32:
+		return strconv.AppendInt(b, int64(v), 10)
+	case int64:
+		return strconv.AppendInt(b, v, 10)
+	case uint:
+		return strconv.AppendUint(b, uint64(v), 10)
+	case uint8:
+		return strconv.AppendUint(b, uint64(v), 10)
+	case uint16:
+		return strconv.AppendUint(b, uint64(v), 10)
+	case uint32:
+		return strconv.AppendUint(b, uint64(v), 10)
+	case uint64:
+		return strconv.AppendUint(b, v, 10)
+	case float32:
+		return strconv.AppendFloat(b, float64(v), 'f', -1, 64)
+	case float64:
+		return strconv.AppendFloat(b, v, 'f', -1, 64)
+	case bool:
+		if v {
+			return append(b, "true"...)
+		}
+		return append(b, "false"...)
+	case time.Time:
+		return v.AppendFormat(b, time.RFC3339Nano)
+	default:
+		return append(b, fmt.Sprint(v)...)
+	}
+}
+
+func appendUTF8String(b []byte, s string) []byte {
+	for _, r := range s {
+		b = appendRune(b, r)
+	}
+	return b
+}
+
+func appendRune(b []byte, r rune) []byte {
+	if r < utf8.RuneSelf {
+		switch c := byte(r); c {
+		case '\n':
+			return append(b, "\\n"...)
+		case '\r':
+			return append(b, "\\r"...)
+		default:
+			return append(b, c)
+		}
+	}
+
+	l := len(b)
+	b = append(b, make([]byte, utf8.UTFMax)...)
+	n := utf8.EncodeRune(b[l:l+utf8.UTFMax], r)
+	b = b[:l+n]
+
+	return b
+}