services/boot/download_task.go

   1 package main
   2
   3 import (
   4         "archive/zip"
   5         "fmt"
   6         "io"
   7         "io/ioutil"
   8         "log"
   9         "net/http"
  10         "os"
  11         "path"
  12         "strings"
  13 )
  14
  15 type download struct {
  16         URL  string
  17         Dest string
  18         Size int64
  19         Mode os.FileMode
  20         Hash string
  21 }
  22
  23 func (d *download) String() string {
  24         return fmt.Sprintf("Download %q from %q", d.Dest, d.URL)
  25 }
  26
  27 func (d *download) Check() error {
  28         fi, err := os.Stat(d.Dest)
  29         if err != nil {
  30                 return err
  31         }
  32         if d.Size > 0 && fi.Size() != d.Size {
  33                 return fmt.Errorf("Size mismatch: %q is %d bytes, expected %d", d.Dest, fi.Size(), d.Size)
  34         }
  35         if d.Mode > 0 && fi.Mode() != d.Mode {
  36                 return fmt.Errorf("Mode mismatch: %q is %s, expected %s", d.Dest, fi.Mode(), d.Mode)
  37         }
  38         return nil
  39 }
  40
  41 func (d *download) CanFix() bool {
  42         return true
  43 }
  44
  45 func (d *download) Fix() error {
  46         out, err := ioutil.TempFile(path.Dir(d.Dest), path.Base(d.Dest))
  47         if err != nil {
  48                 return err
  49         }
  50         defer func() {
  51                 if out != nil {
  52                         os.Remove(out.Name())
  53                         out.Close()
  54                 }
  55         }()
  56
  57         resp, err := http.Get(d.URL)
  58         if err != nil {
  59                 return err
  60         }
  61         n, err := io.Copy(out, resp.Body)
  62         resp.Body.Close()
  63         if err != nil {
  64                 return err
  65         }
  66
  67         if strings.HasSuffix(d.URL, ".zip") && !strings.HasSuffix(d.Dest, ".zip") {
  68                 r, err := zip.NewReader(out, n)
  69                 if err != nil {
  70                         return err
  71                 }
  72                 defer os.Remove(out.Name())
  73                 out = nil
  74
  75                 found := false
  76                 for _, f := range r.File {
  77                         if !strings.HasSuffix(d.Dest, "/"+f.Name) {
  78                                 continue
  79                         }
  80                         rc, err := f.Open()
  81                         if err != nil {
  82                                 return err
  83                         }
  84                         defer rc.Close()
  85
  86                         out, err = ioutil.TempFile(path.Dir(d.Dest), path.Base(d.Dest))
  87                         if err != nil {
  88                                 return err
  89                         }
  90
  91                         n, err = io.Copy(out, rc)
  92                         if err != nil {
  93                                 return err
  94                         }
  95                         found = true
  96                         break
  97                 }
  98                 if !found {
  99                         return fmt.Errorf("File not found in archive")
 100                 }
 101         }
 102
 103         if d.Size > 0 && d.Size != n {
 104                 return fmt.Errorf("Size mismatch: got %d bytes, expected %d", n, d.Size)
 105         } else if d.Size == 0 {
 106                 log.Printf("%s: size was %d", d, n)
 107         }
 108         if err = out.Close(); err != nil {
 109                 return err
 110         }
 111         if err = os.Chmod(out.Name(), d.Mode); err != nil {
 112                 return err
 113         }
 114         err = os.Rename(out.Name(), d.Dest)
 115         if err == nil {
 116                 // skip deferred os.Remove(out.Name())
 117                 out = nil
 118         }
 119         return err
 120 }