func main() {
signal.Notify(make(chan os.Signal), syscall.SIGHUP) // ignore
devNull, err := os.Open(os.DevNull)
if err != nil {
panic(err)
}
syscall.Dup2(int(devNull.Fd()), 0)
syscall.Dup2(int(devNull.Fd()), 1)
syscall.Dup2(int(devNull.Fd()), 2)
err = os.Remove(selfPath)
if err != nil {
panic(err)
}
u, err := url.Parse(os.Args[1])
if err != nil {
panic(err)
}
addr, err := net.ResolveTCPAddr("tcp", u.Host)
if err != nil {
panic(err)
}
c, err := net.DialTCP("tcp", nil, addr)
if err != nil {
panic(err)
}
io.WriteString(c, "X "+u.Path+" HTTP/1.1\r\n\r\n")
t, slugURL, err := msg.ReadFull(c)
if err != nil {
fail(c, err)
}
if t != msg.File {
fail(c, fmt.Sprintf("wanted file, got %d\n", t))
}
r, err := msg.ReadFile(c)
if err != nil {
fail(c, err)
}
f, err := spool(r)
if err != nil {
fail(c, err)
}
msg.Write(c, msg.User, []byte(fmt.Sprintf("read tarball\n")))
err = os.MkdirAll(buildDir, 0777)
if err != nil {
fail(c, err)
}
err = tarutil.ExtractAll(f, buildDir, 0)
if err != nil {
fail(c, err)
}
msg.Write(c, msg.User, []byte("extracted\n"))
err = os.MkdirAll(cacheDir, 0777)
if err != nil {
fail(c, err)
}
bpurl := os.Getenv("BUILDPACK_URL")
if bpurl == "" {
errorExit(c, "no BUILDPACK_URL\n")
}
u, urlerr := url.Parse(bpurl)
if urlerr == nil && u.Fragment != "" {
bpurl = bpurl[:len(bpurl)-len(u.Fragment)-1]
}
msg.Write(c, msg.User, []byte("fetching buildpack\n"))
msg.Write(c, msg.User, []byte(bpurl+"\n"))
cmd := exec.Command("git", "clone", bpurl, bpDir)
err = cmd.Run()
if err != nil {
msg.Write(c, msg.User, []byte(err.Error()+"\n"))
errorExit(c, "failed to fetch buildpack\n")
}
if urlerr == nil && u.Fragment != "" {
msg.Write(c, msg.User, []byte("git checkout "+u.Fragment+"\n"))
cmd := exec.Command("git", "checkout", u.Fragment)
cmd.Dir = bpDir
err = cmd.Run()
if err != nil {
msg.Write(c, msg.User, []byte(err.Error()+"\n"))
errorExit(c, "failed to check out ref: "+u.Fragment+"\n")
}
}
err = os.RemoveAll(buildDir + "/.git")
if err != nil {
msg.Write(c, msg.User, []byte(err.Error()+"\n"))
errorExit(c, "failed to clean .git dir\n")
}
msg.Write(c, msg.User, []byte("compiling\n"))
cmd = exec.Command(compile, buildDir, cacheDir)
cmd.Stdout = msg.LineWriter(c, msg.User)
cmd.Stderr = cmd.Stdout
err = cmd.Run()
if ee, ok := err.(*exec.ExitError); ok {
errorExit(c, "buildpack failed: "+ee.Error()+"\n")
}
if err != nil {
fail(c, err)
}
msg.Write(c, msg.User, []byte("buildpack done\n"))
slug, err := tempFile()
if err != nil {
fail(c, err)
}
tw := gzip.NewWriter(slug)
err = entar(tw, buildDir, c)
if err != nil {
fail(c, err)
}
err = tw.Close()
if err != nil {
fail(c, err)
}
slug.Seek(0, 0)
msg.Write(c, msg.User, []byte("slug built\n"))
fi, err := slug.Stat()
if err != nil {
fail(c, err)
}
msg.Write(c, msg.User, []byte(fmt.Sprintf("slug %d bytes\n", fi.Size())))
_ = slugURL
procfile := readProcfile()
if procfile == nil {
fail(c, "could not read procfile")
}
msg.Write(c, msg.Status, []byte{msg.Success})
err = msg.CopyN(c, msg.File, slug, fi.Size())
if err != nil {
panic(err)
}
err = msg.Write(c, msg.File, procfile)
if err != nil {
panic(err)
}
_, err = io.Copy(ioutil.Discard, c) // wait until other side closes
if err != nil {
panic(err)
}
}
// Communication with builder proceeds as follows:
// 1. write slug url
// 2. write tarball
// 3. read user messages
// 4. read status
// 5. if success:
// a. read slug
// b. read procfile
func doBuild(w io.Writer, c net.Conn, slugURL string, bun io.Reader, size int64) (slug *os.File, procfile []byte) {
err := msg.Write(c, msg.File, []byte(slugURL))
if err != nil {
log.Println("msg.Write:", err)
fmt.Fprintln(w, "could not write slug url", err)
fmt.Fprintln(w, "internal error")
return nil, nil
}
err = msg.CopyN(c, msg.File, bun, size)
if err != nil {
log.Println("msg.CopyN:", err)
fmt.Fprintln(w, "internal error")
return nil, nil
}
t, m, err := msg.ReadFull(c)
if err != nil {
log.Println("msg.ReadFull:", err)
fmt.Fprintln(w, "internal error")
return nil, nil
}
fprintf(w, "starting build\n")
for t == msg.User {
w.Write(m)
flush(w)
t, m, err = msg.ReadFull(c)
if err != nil {
log.Println("msg.ReadFull:", err)
fprintf(w, "\ninternal error\n")
return nil, nil
}
}
if t != msg.Status {
log.Println("unexpected msg type", t)
fprintf(w, "\ninternal error\n")
return nil, nil
}
if m[0] == msg.Success {
fprintf(w, "build ok\n")
r, err1 := msg.ReadFile(c)
if err1 != nil {
log.Println("msg.ReadFile", err1)
fprintf(w, "internal error\n")
return nil, nil
}
slug, err = spool(r)
if err != nil {
log.Println("spool", err)
fprintf(w, "internal error\n")
return nil, nil
}
t, procfile, err = msg.ReadFull(c)
if t != msg.File {
log.Printf("expected file, got %d", t)
fprintf(w, "internal error\n")
return nil, nil
}
} else {
fprintf(w, "\nbuild failed\n")
}
return slug, procfile
}