From 27f0897faa46cd1507b819b318c4b78f4e49a81b Mon Sep 17 00:00:00 2001
From: Liang Ding <dl88250@gmail.com>
Date: Fri, 12 Dec 2014 16:50:59 +0800
Subject: [PATCH] package log

---
 log/logs.go | 133 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 133 insertions(+)
 create mode 100755 log/logs.go

diff --git a/log/logs.go b/log/logs.go
new file mode 100755
index 0000000..47e4dbb
--- /dev/null
+++ b/log/logs.go
@@ -0,0 +1,133 @@
+// Copyright (c) 2014, B3log
+//
+// 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 log includes logging related manipulations.
+//
+// 	logger := log.NewLogger(os.Stdout, log.Debug)
+//
+// 	logger.Debug("debug message")
+// 	logger.Info("info message")
+// 	logger.Warn("warning message")
+// 	logger.Error("error message")
+//
+//	logger.Errorf("formatted %s message", "error")
+package log
+
+import (
+	"fmt"
+	"io"
+	stdlog "log"
+)
+
+// Logging level.
+const (
+	Debug = iota
+	Info
+	Warn
+	Error
+)
+
+// Logger is a simple logger with level.
+// The underlying logger is the Go standard logging "log".
+type Logger struct {
+	level  int
+	logger *stdlog.Logger
+}
+
+// NewLogger creates a logger.
+func NewLogger(out io.Writer, level int) *Logger {
+	ret := &Logger{level: level, logger: stdlog.New(out, "", stdlog.Ldate|stdlog.Ltime|stdlog.Lshortfile)}
+
+	return ret
+}
+
+// Debug prints debug level message.
+func (l *Logger) Debug(v ...interface{}) {
+	if Debug < l.level {
+		return
+	}
+
+	l.logger.SetPrefix("D ")
+	l.logger.Output(2, fmt.Sprint(v...))
+}
+
+// Debugf prints debug level message with format.
+func (l *Logger) Debugf(format string, v ...interface{}) {
+	if Debug < l.level {
+		return
+	}
+
+	l.logger.SetPrefix("D ")
+	l.logger.Output(2, fmt.Sprintf(format, v...))
+}
+
+// Info prints info level message.
+func (l *Logger) Info(v ...interface{}) {
+	if Info < l.level {
+		return
+	}
+
+	l.logger.SetPrefix("I ")
+	l.logger.Output(2, fmt.Sprint(v...))
+}
+
+// Infof prints info level message with format.
+func (l *Logger) Infof(format string, v ...interface{}) {
+	if Info < l.level {
+		return
+	}
+
+	l.logger.SetPrefix("I ")
+	l.logger.Output(2, fmt.Sprintf(format, v...))
+}
+
+// Warn prints warning level message.
+func (l *Logger) Warn(v ...interface{}) {
+	if Warn < l.level {
+		return
+	}
+
+	l.logger.SetPrefix("W ")
+	l.logger.Output(2, fmt.Sprint(v...))
+}
+
+// Warn prints warning level message with format.
+func (l *Logger) Warnf(format string, v ...interface{}) {
+	if Warn < l.level {
+		return
+	}
+
+	l.logger.SetPrefix("W ")
+	l.logger.Output(2, fmt.Sprintf(format, v...))
+}
+
+// Error prints error level message.
+func (l *Logger) Error(v ...interface{}) {
+	if Error < l.level {
+		return
+	}
+
+	l.logger.SetPrefix("E ")
+	l.logger.Output(2, fmt.Sprint(v...))
+}
+
+// Errorf prints error level message with format.
+func (l *Logger) Errorf(format string, v ...interface{}) {
+	if Error < l.level {
+		return
+	}
+
+	l.logger.SetPrefix("E ")
+	l.logger.Output(2, fmt.Sprintf(format, v...))
+}