Add Build error hook (print exception)

Signed-off-by: Asai Neko <sugar@sne.moe>

internal/exception/builder.go

@@ -2,6 +2,7 @@ package exception
 
 import (
 	"fmt"
+	"log/slog"
 )
 
 // 12 chars len
@@ -17,6 +18,7 @@ type Builder struct {
 	Endpoint string
 	Type     string
 	Original string
+	Error    error
 }
 
 func (self *Builder) SetStatus(s string) *Builder {
@@ -44,12 +46,21 @@ func (self *Builder) SetOriginal(s string) *Builder {
 	return self
 }
 
+func (self *Builder) SetError(e error) *Builder {
+	self.Error = e
+	return self
+}
+
 func (self *Builder) Build() string {
-	return fmt.Sprintf("%s%s%s%s%s",
+	errorCode := fmt.Sprintf("%s%s%s%s%s",
 		self.Status,
 		self.Service,
 		self.Endpoint,
 		self.Type,
 		self.Original,
 	)
+	if self.Error != nil {
+		slog.Warn("Service exception", "id", errorCode, "err", self.Error)
+	}
+	return errorCode
 }