func tailFile(filename string, config tail.Config, done chan bool) {
defer func() { done <- true }()
t, err := tail.TailFile(filename, config)
if err != nil {
fmt.Println(err)
return
}
for line := range t.Lines {
fmt.Println(line.Text)
}
err = t.Wait()
if err != nil {
fmt.Println(err)
}
}
// Read old log lines from a logfile.
func (l *Log) Read(lines int, follow bool, ch chan Data, done chan struct{}) error {
name := l.l.Filename
var seek int64
if lines == 0 {
f, err := os.Open(name)
defer f.Close()
if err != nil {
return err
}
if seek, err = f.Seek(0, os.SEEK_END); err != nil {
return err
}
} else if lines == -1 {
// return all lines
dir := filepath.Dir(name)
files, err := ioutil.ReadDir(dir)
if err != nil {
return err
}
basename := filepath.Base(name)
ext := filepath.Ext(basename)
id := strings.TrimSuffix(basename, ext)
for _, f := range files {
if !(strings.HasPrefix(f.Name(), id+"-") && strings.HasSuffix(f.Name(), ext)) {
continue
}
t, err := tail.TailFile(filepath.Join(dir, f.Name()), tail.Config{
Logger: tail.DiscardingLogger,
})
if err != nil {
return err
}
for line := range t.Lines {
data := Data{}
if err := json.Unmarshal([]byte(line.Text), &data); err != nil {
return err
}
ch <- data
}
}
}
t, err := tail.TailFile(name, tail.Config{
Follow: follow,
ReOpen: follow,
Logger: tail.DiscardingLogger,
Location: &tail.SeekInfo{
Offset: seek,
Whence: os.SEEK_SET,
},
})
if err != nil {
return err
}
outer:
for {
select {
case line, ok := <-t.Lines:
if !ok {
break outer
}
data := Data{}
if err := json.Unmarshal([]byte(line.Text), &data); err != nil {
return err
}
ch <- data
case <-done:
break outer
case <-time.After(200 * time.Millisecond):
if !l.closed {
continue
}
break outer
}
}
close(ch) // send a close event so we know everything was read
return nil
}