add file/line numbers to logs

Signed-off-by: Steve Kriss <steve@heptio.com>

pkg/cmd/server/server.go

@@ -86,7 +86,7 @@ func NewCommand() *cobra.Command {
 			}
 			logrus.Infof("setting log-level to %s", strings.ToUpper(logLevel.String()))
 
-			logger := newLogger(logLevel, &logging.ErrorLocationHook{})
+			logger := newLogger(logLevel, &logging.ErrorLocationHook{}, &logging.LogLocationHook{})
 
 			s, err := newServer(kubeconfig, fmt.Sprintf("%s-%s", c.Parent().Name(), c.Name()), logger)
 

pkg/util/logging/log_location_hook.go

@@ -0,0 +1,68 @@
+/*
+Copyright 2017 Heptio Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package logging
+
+import (
+	"fmt"
+	"runtime"
+	"strings"
+
+	"github.com/sirupsen/logrus"
+)
+
+const logLocationField = "logSource"
+
+// LogLocationHook is a logrus hook that attaches location information
+// to log entries, i.e. the file and line number of the logrus log call.
+type LogLocationHook struct {
+}
+
+func (h *LogLocationHook) Levels() []logrus.Level {
+	return logrus.AllLevels
+}
+
+func (h *LogLocationHook) Fire(entry *logrus.Entry) error {
+	pcs := make([]uintptr, 64)
+
+	// skip 2 frames:
+	//   runtime.Callers
+	//   github.com/heptio/ark/pkg/util/logging/(*LogLocationHook).Fire
+	n := runtime.Callers(2, pcs)
+
+	// re-slice pcs based on the number of entries written
+	frames := runtime.CallersFrames(pcs[:n])
+
+	// now traverse up the call stack looking for the first non-logrus
+	// func, which will be the logrus invoker
+	var (
+		frame runtime.Frame
+		more  = true
+	)
+
+	for more {
+		frame, more = frames.Next()
+
+		if strings.Contains(frame.File, "github.com/sirupsen/logrus") {
+			continue
+		}
+
+		entry.Data[logLocationField] = fmt.Sprintf("%s:%d", frame.File, frame.Line)
+		break
+	}
+
+	return nil
+}