|
| 1 | +// command server listens on the Unix socket `/run/guest-services/hello.sock` |
| 2 | +// (see `everything.json`) to exercise the ability for the front end to talk to |
| 3 | +// the back end. |
| 4 | +package main |
| 5 | + |
| 6 | +import ( |
| 7 | + "context" |
| 8 | + "errors" |
| 9 | + "fmt" |
| 10 | + "io" |
| 11 | + "log/slog" |
| 12 | + "net" |
| 13 | + "net/http" |
| 14 | + "os" |
| 15 | + "os/signal" |
| 16 | + "syscall" |
| 17 | +) |
| 18 | + |
| 19 | +const ( |
| 20 | + addr = "/run/guest-services/hello.sock" |
| 21 | +) |
| 22 | + |
| 23 | +// Listen on a port and return the listener |
| 24 | +func listen() (net.Listener, error) { |
| 25 | + err := os.Remove(addr) |
| 26 | + if err != nil && !errors.Is(err, os.ErrNotExist) { |
| 27 | + slog.Error("failed to remove old socket", "socket", addr, "error", err) |
| 28 | + } |
| 29 | + listener, err := net.Listen("unix", addr) |
| 30 | + if err == nil { |
| 31 | + return listener, nil |
| 32 | + } |
| 33 | + listener, err = net.Listen("tcp", "") |
| 34 | + if err != nil { |
| 35 | + return nil, fmt.Errorf("failed to listen on fallback TCP: %w", err) |
| 36 | + } |
| 37 | + return listener, nil |
| 38 | +} |
| 39 | + |
| 40 | +// Handle HTTP POST requests |
| 41 | +func handlePost(w http.ResponseWriter, req *http.Request) { |
| 42 | + _, _ = io.Copy(w, req.Body) |
| 43 | +} |
| 44 | + |
| 45 | +func main() { |
| 46 | + listener, err := listen() |
| 47 | + if err != nil { |
| 48 | + slog.Error("failed to listen", "error", err) |
| 49 | + os.Exit(1) |
| 50 | + } |
| 51 | + http.DefaultServeMux.Handle("GET /", http.FileServer(http.Dir("/"))) |
| 52 | + http.DefaultServeMux.HandleFunc("POST /", handlePost) |
| 53 | + |
| 54 | + server := &http.Server{} |
| 55 | + ch := make(chan os.Signal) |
| 56 | + errCh := make(chan error) |
| 57 | + signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM) |
| 58 | + go func() { |
| 59 | + <-ch |
| 60 | + errCh <- server.Shutdown(context.Background()) |
| 61 | + }() |
| 62 | + |
| 63 | + slog.Info("Serving HTTP", "address", listener.Addr().String()) |
| 64 | + err = server.Serve(listener) |
| 65 | + if err != nil && !errors.Is(err, http.ErrServerClosed) { |
| 66 | + slog.Error("server closed", "error", err) |
| 67 | + os.Exit(1) |
| 68 | + } |
| 69 | + if err = <-errCh; err != nil { |
| 70 | + slog.Error("failed to shutdown server", "error", err) |
| 71 | + os.Exit(1) |
| 72 | + } |
| 73 | +} |
0 commit comments