2 uploader -- simplest form file uploader
3 Copyright (C) 2018-2019 Sergey Matveev <stargrave@stargrave.org>
21 "golang.org/x/crypto/blake2b"
22 "golang.org/x/net/netutil"
26 WriteBufSize = 1 << 20
27 FileFieldName = "fileupload"
28 CommentFieldName = "comment"
32 Index = template.Must(template.New("index").Parse(`<html>
33 <head><title>Upload</title></head><body>
34 <form enctype="multipart/form-data" action="/upload/" method="post">
35 <input type="file" name="{{.}}" /><br/>
36 <label for="comment">Optional comment:</label>
37 <textarea name="comment" cols="80" rows="25" name="comment"></textarea><br/>
38 <input type="submit" />
39 </form></body></html>`))
42 func upload(w http.ResponseWriter, r *http.Request) {
43 log.Println(r.RemoteAddr, "connected")
44 if r.Method == http.MethodGet {
45 if err := Index.Execute(w, FileFieldName); err != nil {
46 log.Println(r.RemoteAddr, err)
50 mr, err := r.MultipartReader()
52 log.Println(r.RemoteAddr, err)
55 p, err := mr.NextPart()
57 log.Println(r.RemoteAddr, err)
60 if p.FormName() != FileFieldName {
61 log.Println(r.RemoteAddr, "non file form field")
64 h, err := blake2b.New256(nil)
68 fn := time.Now().Format(time.RFC3339Nano)
69 fd, err := os.OpenFile(fn+".part", os.O_WRONLY|os.O_CREATE, 0600)
71 log.Println(r.RemoteAddr, fn, p.FileName(), err)
74 fdBuf := bufio.NewWriterSize(fd, WriteBufSize)
75 mw := io.MultiWriter(fdBuf, h)
76 n, err := io.Copy(mw, p)
78 log.Println(r.RemoteAddr, fn, p.FileName(), err)
83 log.Println(r.RemoteAddr, fn, p.FileName(), "empty")
84 os.Remove(fn + ".part")
86 fmt.Fprintf(w, "Empty file")
89 if err = fdBuf.Flush(); err != nil {
90 log.Println(r.RemoteAddr, fn, p.FileName(), err)
95 sum := hex.EncodeToString(h.Sum(nil))
96 if err = os.Rename(fn+".part", fn); err != nil {
97 log.Println(r.RemoteAddr, fn, p.FileName(), n, sum, err)
100 fmt.Fprintf(w, "Timestamp: %s\nBytes: %d\nBLAKE2b: %s\n", fn, n, sum)
101 log.Println(r.RemoteAddr, fn, p.FileName(), n, sum)
102 p, err = mr.NextPart()
103 if err != nil || p.FormName() != CommentFieldName {
106 comment, err := ioutil.ReadAll(p)
107 if err != nil || len(comment) == 0 {
110 ioutil.WriteFile(fn+".txt", comment, os.FileMode(0600))
111 go notify(fn, n, string(comment))
115 bind := flag.String("bind", "[::]:8086", "Address to bind to")
116 conns := flag.Int("conns", 2, "Maximal number of connections")
118 ln, err := net.Listen("tcp", *bind)
122 log.Println("listening", *bind)
123 ln = netutil.LimitListener(ln, *conns)
125 ReadHeaderTimeout: 10 * time.Second,
126 MaxHeaderBytes: 10 * (1 << 10),
128 http.HandleFunc("/upload/", upload)