Download 多线程下载 page 页到 filepath, 返回 error
(page int, path string)
| 42 | |
| 43 | // Download 多线程下载 page 页到 filepath, 返回 error |
| 44 | func (i *Illust) Download(page int, path string) error { |
| 45 | const slicecap int64 = 65536 |
| 46 | u := i.ImageUrls[page] |
| 47 | // 获取IP地址 |
| 48 | domain, err := url.Parse(u) |
| 49 | if err != nil { |
| 50 | return err |
| 51 | } |
| 52 | |
| 53 | header := http.Header{ |
| 54 | "Host": []string{domain.Host}, |
| 55 | "Referer": []string{"https://www.pixiv.net/"}, |
| 56 | "User-Agent": []string{"Mozilla/5.0 (Windows NT 6.1; WOW64; rv:6.0) Gecko/20100101 Firefox/6.0"}, |
| 57 | "Cache-Control": []string{"no-cache"}, |
| 58 | } |
| 59 | |
| 60 | // 请求 Header |
| 61 | headreq, err := http.NewRequest("HEAD", u, nil) |
| 62 | if err != nil { |
| 63 | return err |
| 64 | } |
| 65 | headreq.Header = header.Clone() |
| 66 | client := web.NewPixivClient() |
| 67 | headresp, err := client.Do(headreq) |
| 68 | if err != nil { |
| 69 | return err |
| 70 | } |
| 71 | |
| 72 | contentlength, err := strconv.ParseInt(headresp.Header.Get("Content-Length"), 10, 64) |
| 73 | _ = headresp.Body.Close() |
| 74 | if err != nil { |
| 75 | return err |
| 76 | } |
| 77 | |
| 78 | // 多线程下载 |
| 79 | var wg sync.WaitGroup |
| 80 | var start int64 |
| 81 | errs := make(chan error, 8) |
| 82 | buf := make(net.Buffers, 0, contentlength/slicecap+1) |
| 83 | writers := make([]*binary.Writer, 0, contentlength/slicecap+1) |
| 84 | index := 0 |
| 85 | for end := math.Min(start+slicecap, contentlength); ; end += slicecap { |
| 86 | wg.Add(1) |
| 87 | buf = append(buf, nil) |
| 88 | writers = append(writers, nil) |
| 89 | if end > contentlength { |
| 90 | end = contentlength |
| 91 | } |
| 92 | go func(start int64, end int64, index int) { |
| 93 | // fmt.Println(contentlength, start, end) |
| 94 | for failedtimes := 0; failedtimes < 3; failedtimes++ { |
| 95 | req, err := http.NewRequest("GET", u, nil) |
| 96 | if err != nil { |
| 97 | errs <- err |
| 98 | process.SleepAbout1sTo2s() |
| 99 | continue |
| 100 | } |
| 101 | req.Header = header.Clone() |