func (r *Runner) getBuildLog(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
id := ps.ByName("build")
b := &Build{}
if err := r.db.View(func(tx *bolt.Tx) error {
v := tx.Bucket(dbBucket).Get([]byte(id))
if err := json.Unmarshal(v, b); err != nil {
return fmt.Errorf("could not decode build %s: %s", v, err)
}
return nil
}); err != nil {
http.Error(w, err.Error(), 500)
return
}
if b.Finished() {
if b.Version == BuildVersion1 {
http.Redirect(w, req, b.LogURL, http.StatusMovedPermanently)
return
}
if strings.Contains(req.Header.Get("Accept"), "text/event-stream") {
if err := serveBuildLogStream(b, w); err != nil {
http.Error(w, err.Error(), 500)
}
return
}
http.ServeFile(w, req, path.Join(args.AssetsDir, "build-log.html"))
return
}
t, err := tail.TailFile(b.LogFile, tail.Config{Follow: true, MustExist: true})
if err != nil {
http.Error(w, err.Error(), 500)
return
}
if cn, ok := w.(http.CloseNotifier); ok {
go func() {
<-cn.CloseNotify()
t.Stop()
}()
} else {
defer t.Stop()
}
flush := func() {
if fw, ok := w.(http.Flusher); ok {
fw.Flush()
}
}
w.Header().Set("Content-Type", textPlain)
w.WriteHeader(http.StatusOK)
flush()
for line := range t.Lines {
if _, err := io.WriteString(w, line.Text+"\n"); err != nil {
log.Printf("serveBuildLog write error: %s\n", err)
return
}
flush()
if strings.HasPrefix(line.Text, "build finished") {
return
}
}
}
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)
}
}
func getBuildLogStream(b *Build, ch chan string) (stream.Stream, error) {
stream := stream.New()
// if the build hasn't finished, tail the log from disk
if !b.Finished() {
t, err := tail.TailFile(b.LogFile, tail.Config{Follow: true, MustExist: true})
if err != nil {
return nil, err
}
go func() {
defer t.Stop()
defer close(ch)
for {
select {
case line, ok := <-t.Lines:
if !ok {
stream.Error = t.Err()
return
}
select {
case ch <- line.Text:
case <-stream.StopCh:
return
}
if strings.HasPrefix(line.Text, "build finished") {
return
}
case <-stream.StopCh:
return
}
}
}()
return stream, nil
}
// get the multipart log from S3 and serve just the "build.log" file
res, err := http.Get(b.LogURL)
if err != nil {
return nil, err
}
if res.StatusCode != http.StatusOK {
res.Body.Close()
return nil, fmt.Errorf("unexpected status %d getting build log", res.StatusCode)
}
_, params, err := mime.ParseMediaType(res.Header.Get("Content-Type"))
if err != nil {
res.Body.Close()
return nil, err
}
go func() {
defer res.Body.Close()
defer close(ch)
mr := multipart.NewReader(res.Body, params["boundary"])
for {
select {
case <-stream.StopCh:
return
default:
}
p, err := mr.NextPart()
if err != nil {
stream.Error = err
return
}
if p.FileName() != "build.log" {
continue
}
s := bufio.NewScanner(p)
for s.Scan() {
select {
case ch <- s.Text():
case <-stream.StopCh:
return
}
}
return
}
}()
return stream, nil
}
// 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
}
defer t.Stop()
closed := l.closed
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 <-closed:
// StopAtEOF will wait until the log hits an EOF before closing
// t.Lines
go t.StopAtEOF()
// make sure that we don't hit this path again
closed = nil
}
}
close(ch) // send a close event so we know everything was read
return nil
}