func()

in backend/analyzer/LiveUpdate.go [34:80]
40 lines of code
9 McCabe index (conditional complexity)

func (a *Analyzer) addWatcher(logFile string, entityIndex int) {
	for _, watcher := range a.fileWatchers {
		if watcher.Filename == logFile {
			return
		}
	}
	t, err := tail.TailFile(logFile, tail.Config{
		Follow:   true,
		Poll:     true,
		Location: &tail.SeekInfo{Offset: 0, Whence: io.SeekEnd}, // <- line changed
	})
	if err != nil {
		log.Println(err)
	}
	a.fileWatchers = append(a.fileWatchers, t)
	log.Printf("Enabled File watcher for: %v", logFile)

	previousLogEntry := ""
	// t.Lines channel sends new lines of a file to "for" loop.
	// Inside the loop, lines are being checked by ConvertStringToLogs function.
	// If a line could be converted to log entry (ConvertStringToLogs return nil error), it is being remembered as previousLogEntry.
	// If [the next line is also a log entry],  previousLogEntry is being appended to the logs entry list. If next line is the last line of file, it also is being appended to the logs entry list.
	// If [the next line is not a log entry], it is being appended to the previous log line (as it is part of the same log entry).
	for line := range t.Lines {
		f, _ := os.Open(t.Filename)
		seek, _ := f.Seek(0, 2)
		lineIsLast := line.SeekInfo.Offset == seek
		if _, err := a.DynamicEntities[entityIndex].ConvertStringToLogs(line.Text); err == nil {
			if len(previousLogEntry) != 0 {
				a.attachToLogsStruct(previousLogEntry, entityIndex, t.Filename)
			}
			if lineIsLast {
				a.attachToLogsStruct(line.Text, entityIndex, t.Filename)
				previousLogEntry = ""
			} else {
				previousLogEntry = line.Text
			}
		} else {
			previousLogEntry = previousLogEntry + "\n" + line.Text
			if lineIsLast {
				a.attachToLogsStruct(previousLogEntry, entityIndex, t.Filename)
				previousLogEntry = ""
			}
		}

	}
}