Panic on any logger errors

Any template errors instead of IO
errors are caught in validation.

pkg/logger/logger.go

@@ -137,15 +137,8 @@ func (l *Logger) Output(calldepth int, message string) {
 		File:      file,
 		Message:   message,
 	})
-	// Fallback for template errors
 	if err != nil {
-		_, ferr := fmt.Fprintf(l.writer, "[%s] [%s] %s",
+		panic(err)
-			FormatTimestamp(now),
-			file,
-			message)
-		if ferr != nil {
-			panic(ferr)
-		}
 	}
 
 	_, err = l.writer.Write([]byte("\n"))
@@ -184,17 +177,8 @@ func (l *Logger) PrintAuthf(username string, req *http.Request, status AuthStatu
 		Status:        string(status),
 		Message:       fmt.Sprintf(format, a...),
 	})
-	// Fallback for template errors
 	if err != nil {
-		_, ferr := fmt.Fprintf(l.writer, "%s - %s [%s] [%s] %s",
+		panic(err)
-			client,
-			username,
-			FormatTimestamp(now),
-			string(status),
-			fmt.Sprintf(format, a...))
-		if ferr != nil {
-			panic(ferr)
-		}
 	}
 
 	_, err = l.writer.Write([]byte("\n"))
@@ -250,14 +234,8 @@ func (l *Logger) PrintReq(username, upstream string, req *http.Request, url url.
 		UserAgent:       fmt.Sprintf("%q", req.UserAgent()),
 		Username:        username,
 	})
-	// Fallback for template errors
 	if err != nil {
-		_, ferr := fmt.Fprintf(l.writer, "%s - %s [%s] %s %s %s %q %s %q %d %d %0.3f",
+		panic(err)
-			client, username, FormatTimestamp(ts), req.Host, req.Method, upstream,
-			url.RequestURI(), req.Proto, req.UserAgent(), status, size, duration)
-		if ferr != nil {
-			panic(ferr)
-		}
 	}
 
 	_, err = l.writer.Write([]byte("\n"))