reader.go

// Copyright 2018 The OpenPitrix Authors. All rights reserved.
// Use of this source code is governed by a Apache license
// that can be found in the LICENSE file.

package logger

import (
	"fmt"
	"strconv"
	"strings"
	"time"
)

type logMessage struct {
	Time      time.Time
	RequestId string
	MessageId []string
	Level     string
	Text      string
	File      string
	Line      int
}

func readLogs(logs string) []logMessage {
	const (
		timeLayout = "2006-01-02 15:04:05.99999"
		minLogLen  = len(timeLayout + " " + "-INFO-")
	)
	var (
		results []logMessage
	)

	for _, s := range strings.Split(logs, "\n") {
		s = strings.TrimSpace(s)
		if len(s) < minLogLen {
			continue
		}

		// 1. parse time
		when, err := time.Parse(timeLayout, strings.TrimSpace(s[:len(timeLayout)]))
		if err != nil {
			continue
		}

		// skip time
		s = s[len(timeLayout):]

		// 2. parse level
		var level string
		fmt.Sscanf(s, "%s", &level)
		if level == "" {
			continue
		}

		// skip level
		if len(s) > len(level) {
			s = s[len(level)+1:]
		} else {
			s = s[len(level):]
		}

		// fix level
		level = strings.Trim(level, "-")

		// 3. parse (file:line)
		filenameStartPos := strings.LastIndex(s, "(")
		lineStartPos := strings.LastIndex(s, ":")
		lineEndPos := strings.LastIndex(s, ")")

		var filename string
		var fileline int
		if filenameStartPos >= 0 && lineStartPos > (filenameStartPos+1) {
			filename = s[filenameStartPos+1 : lineStartPos]
		}
		if lineStartPos >= 0 && lineEndPos > (lineStartPos+1) {
			fileline, _ = strconv.Atoi(s[lineStartPos+1 : lineEndPos])
		}

		// 4. parse {msg-id|...@req-id}
		msgIdStartPos := strings.LastIndex(s, "{")
		reqIdStartPos := strings.LastIndex(s, "@")
		reqIdEndPos := strings.LastIndex(s, "}")

		var msgId []string
		var reqId string
		if msgIdStartPos >= 0 && reqIdStartPos > (msgIdStartPos+1) {
			msgId = strings.Split(s[msgIdStartPos+1:reqIdStartPos], "|")
		}
		if reqIdStartPos < reqIdEndPos {
			reqId = s[reqIdStartPos+1 : reqIdEndPos]
		}

		// 5. parse text
		var text string
		if filename != "" {
			text = strings.TrimSpace(s[:filenameStartPos])
		} else {
			text = strings.TrimSpace(s)
		}

		// OK
		results = append(results, logMessage{
			Time:      when,
			RequestId: reqId,
			MessageId: msgId,
			Level:     strings.Trim(level, "-"),
			Text:      text,
			File:      filename,
			Line:      fileline,
		})
	}

	return results
}