Merge pull request #1 from sdual/fix-comment

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README.md

@@ -1 +1,31 @@
 # roachslog
+
+[![Go](https://github.com/sdual/roachslog/actions/workflows/go-test.yml/badge.svg)](https://github.com/sdual/roachslog/actions/workflows/go-test.yml)
+
+## Examples
+
+```go
+package main
+
+import (
+	"log/slog"
+	"os"
+
+	"github.com/cockroachdb/errors"
+	"github.com/sdual/roachslog"
+)
+
+func main() {
+	ops := slog.HandlerOptions{
+		AddSource: true,
+		Level:     slog.LevelInfo,
+	}
+
+	handler := slog.NewJSONHandler(os.Stdout, &ops)
+	rsHandler := roachslog.NewReachSlogHandler(handler)
+	slog.SetDefault(slog.New(rsHandler))
+
+	err := errors.New("error")
+	slog.Error("error occurred", roachslog.Err(err))
+}
+```

arr_attr.go

@@ -0,0 +1,11 @@
+package roachslog
+
+import (
+	"log/slog"
+)
+
+const errAttrKey = "error"
+
+func Err(err error) slog.Attr {
+	return slog.Any(errAttrKey, err)
+}

handler.go

@@ -7,40 +7,29 @@ import (
 	"github.com/cockroachdb/errors"
 )
 
-const (
-	defaultErrorAttrKey     = "error"
-	defaultStactraceAttrKey = "stacktrace"
-)
+const defaultStactraceAttrKey = "stacktrace"
 
 type (
+	// RoachSlogHandler is the slog handler to format stacktrace of logs cockroachdb/errors.
 	RoachSlogHandler struct {
 		handler       slog.Handler
-		errAttrKey    string
 		stacktraceKey string
 	}
 
 	opt func(*RoachSlogHandler)
 )
 
 // NewReachSlogHandler creates a new RoachSlogHandler instance.
-func NewReachSlogHandler(handler slog.Handler, opts ...opt) RoachSlogHandler {
-
+func NewReachSlogHandler(handler slog.Handler, opts ...opt) slog.Handler {
 	rs := &RoachSlogHandler{
 		handler:       handler,
-		errAttrKey:    defaultErrorAttrKey,
 		stacktraceKey: defaultStactraceAttrKey,
 	}
 
 	for _, option := range opts {
 		option(rs)
 	}
-	return *rs
-}
-
-func WithErrorAttrKey(key string) opt {
-	return func(rs *RoachSlogHandler) {
-		rs.errAttrKey = key
-	}
+	return rs
 }
 
 func WithStacktraceAttrKey(key string) opt {
@@ -56,22 +45,18 @@ func (rs *RoachSlogHandler) Enabled(ctx context.Context, level slog.Level) bool
 func (rs *RoachSlogHandler) Handle(ctx context.Context, record slog.Record) error {
 	var stacktrace string
 	record.Attrs(func(attr slog.Attr) bool {
-		if attr.Key == rs.errAttrKey {
-			err, ok := attr.Value.Any().(error)
-			// If the cast to type error fails, no information about the error is logged.
+		if attr.Key == errAttrKey {
+			// If the cast to error data type fails, no information about the error is logged.
 			// The value of the error data type should be available as the value corresponding to the specified key (errAttrKey).
-			if !ok {
-				return false
-			}
-			stacktrace, ok = extractStacktrace(err)
-			if !ok {
-				return false
+			if err, ok := attr.Value.Any().(error); ok {
+				stacktrace = extractStacktrace(err)
+				record.AddAttrs(slog.String(rs.stacktraceKey, stacktrace))
 			}
+			return false
 		}
 		return true
 	})
 
-	record.AddAttrs(slog.String(rs.stacktraceKey, stacktrace))
 	return rs.handler.Handle(ctx, record)
 }
 
@@ -82,10 +67,10 @@ func (rs *RoachSlogHandler) WithGroup(g string) slog.Handler {
 	return &RoachSlogHandler{handler: rs.handler.WithGroup(g)}
 }
 
-func extractStacktrace(err error) (string, bool) {
+func extractStacktrace(err error) string {
 	safeDetails := errors.GetSafeDetails(err).SafeDetails
 	if len(safeDetails) > 0 {
-		return safeDetails[0], true
+		return safeDetails[0]
 	}
-	return "", false
+	return ""
 }