TUN-528: Move cloudflared into a separate repo

vendor/github.com/rifflock/lfshook/lfshook.go

@@ -0,0 +1,192 @@
+// Package lfshook is hook for sirupsen/logrus that used for writing the logs to local files.
+package lfshook
+
+import (
+	"fmt"
+	"github.com/sirupsen/logrus"
+	"io"
+	"log"
+	"os"
+	"path/filepath"
+	"reflect"
+	"sync"
+)
+
+// We are logging to file, strip colors to make the output more readable.
+var defaultFormatter = &logrus.TextFormatter{DisableColors: true}
+
+// PathMap is map for mapping a log level to a file's path.
+// Multiple levels may share a file, but multiple files may not be used for one level.
+type PathMap map[logrus.Level]string
+
+// WriterMap is map for mapping a log level to an io.Writer.
+// Multiple levels may share a writer, but multiple writers may not be used for one level.
+type WriterMap map[logrus.Level]io.Writer
+
+// LfsHook is a hook to handle writing to local log files.
+type LfsHook struct {
+	paths     PathMap
+	writers   WriterMap
+	levels    []logrus.Level
+	lock      *sync.Mutex
+	formatter logrus.Formatter
+
+	defaultPath      string
+	defaultWriter    io.Writer
+	hasDefaultPath   bool
+	hasDefaultWriter bool
+}
+
+// NewHook returns new LFS hook.
+// Output can be a string, io.Writer, WriterMap or PathMap.
+// If using io.Writer or WriterMap, user is responsible for closing the used io.Writer.
+func NewHook(output interface{}, formatter logrus.Formatter) *LfsHook {
+	hook := &LfsHook{
+		lock: new(sync.Mutex),
+	}
+
+	hook.SetFormatter(formatter)
+
+	switch output.(type) {
+	case string:
+		hook.SetDefaultPath(output.(string))
+		break
+	case io.Writer:
+		hook.SetDefaultWriter(output.(io.Writer))
+		break
+	case PathMap:
+		hook.paths = output.(PathMap)
+		for level := range output.(PathMap) {
+			hook.levels = append(hook.levels, level)
+		}
+		break
+	case WriterMap:
+		hook.writers = output.(WriterMap)
+		for level := range output.(WriterMap) {
+			hook.levels = append(hook.levels, level)
+		}
+		break
+	default:
+		panic(fmt.Sprintf("unsupported level map type: %v", reflect.TypeOf(output)))
+	}
+
+	return hook
+}
+
+// SetFormatter sets the format that will be used by hook.
+// If using text formatter, this method will disable color output to make the log file more readable.
+func (hook *LfsHook) SetFormatter(formatter logrus.Formatter) {
+	if formatter == nil {
+		formatter = defaultFormatter
+	} else {
+		switch formatter.(type) {
+		case *logrus.TextFormatter:
+			textFormatter := formatter.(*logrus.TextFormatter)
+			textFormatter.DisableColors = true
+		}
+	}
+
+	hook.formatter = formatter
+}
+
+// SetDefaultPath sets default path for levels that don't have any defined output path.
+func (hook *LfsHook) SetDefaultPath(defaultPath string) {
+	hook.defaultPath = defaultPath
+	hook.hasDefaultPath = true
+}
+
+// SetDefaultWriter sets default writer for levels that don't have any defined writer.
+func (hook *LfsHook) SetDefaultWriter(defaultWriter io.Writer) {
+	hook.defaultWriter = defaultWriter
+	hook.hasDefaultWriter = true
+}
+
+// Fire writes the log file to defined path or using the defined writer.
+// User who run this function needs write permissions to the file or directory if the file does not yet exist.
+func (hook *LfsHook) Fire(entry *logrus.Entry) error {
+	if hook.writers != nil || hook.hasDefaultWriter {
+		return hook.ioWrite(entry)
+	} else if hook.paths != nil || hook.hasDefaultPath {
+		return hook.fileWrite(entry)
+	}
+
+	return nil
+}
+
+// Write a log line to an io.Writer.
+func (hook *LfsHook) ioWrite(entry *logrus.Entry) error {
+	var (
+		writer io.Writer
+		msg    []byte
+		err    error
+		ok     bool
+	)
+
+	hook.lock.Lock()
+	defer hook.lock.Unlock()
+
+	if writer, ok = hook.writers[entry.Level]; !ok {
+		if hook.hasDefaultWriter {
+			writer = hook.defaultWriter
+		} else {
+			return nil
+		}
+	}
+
+	// use our formatter instead of entry.String()
+	msg, err = hook.formatter.Format(entry)
+
+	if err != nil {
+		log.Println("failed to generate string for entry:", err)
+		return err
+	}
+	_, err = writer.Write(msg)
+	return err
+}
+
+// Write a log line directly to a file.
+func (hook *LfsHook) fileWrite(entry *logrus.Entry) error {
+	var (
+		fd   *os.File
+		path string
+		msg  []byte
+		err  error
+		ok   bool
+	)
+
+	hook.lock.Lock()
+	defer hook.lock.Unlock()
+
+	if path, ok = hook.paths[entry.Level]; !ok {
+		if hook.hasDefaultPath {
+			path = hook.defaultPath
+		} else {
+			return nil
+		}
+	}
+
+	dir := filepath.Dir(path)
+	os.MkdirAll(dir, os.ModePerm)
+
+	fd, err = os.OpenFile(path, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0666)
+	if err != nil {
+		log.Println("failed to open logfile:", path, err)
+		return err
+	}
+	defer fd.Close()
+
+	// use our formatter instead of entry.String()
+	msg, err = hook.formatter.Format(entry)
+
+	if err != nil {
+		log.Println("failed to generate string for entry:", err)
+		return err
+	}
+	fd.Write(msg)
+	return nil
+}
+
+// Levels returns configured log levels.
+func (hook *LfsHook) Levels() []logrus.Level {
+	return logrus.AllLevels
+}