internal/download: move download logic to this package

also disable http2 when downloading, may fix some issue

For #1563

cmd/gocq/login.go

@@ -15,9 +15,9 @@ import (
 	"github.com/mattn/go-colorable"
 	"github.com/pkg/errors"
 	log "github.com/sirupsen/logrus"
-	"github.com/tidwall/gjson"
 
 	"github.com/Mrs4s/go-cqhttp/global"
+	"github.com/Mrs4s/go-cqhttp/internal/download"
 )
 
 var console = bufio.NewReader(os.Stdin)
@@ -243,12 +243,11 @@ func getTicket(u string) (str string) {
 }
 
 func fetchCaptcha(id string) string {
-	data, err := global.GetBytes("https://captcha.go-cqhttp.org/captcha/ticket?id=" + id)
+	g, err := download.Request{URL: "https://captcha.go-cqhttp.org/captcha/ticket?id=" + id}.JSON()
 	if err != nil {
 		log.Warnf("获取 Ticket 时出现错误: %v", err)
 		return ""
 	}
-	g := gjson.ParseBytes(data)
 	if g.Get("ticket").Exists() {
 		return g.Get("ticket").String()
 	}

coolq/api.go

@@ -27,6 +27,7 @@ import (
 	"github.com/Mrs4s/go-cqhttp/global"
 	"github.com/Mrs4s/go-cqhttp/internal/base"
 	"github.com/Mrs4s/go-cqhttp/internal/cache"
+	"github.com/Mrs4s/go-cqhttp/internal/download"
 	"github.com/Mrs4s/go-cqhttp/internal/param"
 	"github.com/Mrs4s/go-cqhttp/modules/filter"
 )
@@ -1545,12 +1546,8 @@ func (bot *CQBot) CQGetImage(file string) global.MSG {
 		}
 		local := path.Join(global.CachePath, file+path.Ext(msg["filename"].(string)))
 		if !global.PathExists(local) {
-			if body, err := global.HTTPGetReadCloser(msg["url"].(string)); err == nil {
-				f, _ := os.OpenFile(local, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o0644)
-				_, _ = f.ReadFrom(body)
-				_ = body.Close()
-				_ = f.Close()
-			} else {
+			r := download.Request{URL: msg["url"].(string)}
+			if err := r.WriteToFile(local); err != nil {
 				log.Warnf("下载图片 %v 时出现错误: %v", msg["url"], err)
 				return Failed(100, "DOWNLOAD_IMAGE_ERROR", err.Error())
 			}
@@ -1593,7 +1590,8 @@ func (bot *CQBot) CQDownloadFile(url string, headers gjson.Result, threadCount i
 			return Failed(100, "DELETE_FILE_ERROR", err.Error())
 		}
 	}
-	if err := global.DownloadFileMultiThreading(url, file, 0, threadCount, h); err != nil {
+	r := download.Request{URL: url, Header: h}
+	if err := r.WriteToFileMultiThreading(file, threadCount); err != nil {
 		log.Warnf("下载链接 %v 时出现错误: %v", url, err)
 		return Failed(100, "DOWNLOAD_FILE_ERROR", err.Error())
 	}

coolq/cqcode.go

@@ -29,6 +29,7 @@ import (
 	"github.com/Mrs4s/go-cqhttp/global"
 	"github.com/Mrs4s/go-cqhttp/internal/base"
 	"github.com/Mrs4s/go-cqhttp/internal/cache"
+	"github.com/Mrs4s/go-cqhttp/internal/download"
 	"github.com/Mrs4s/go-cqhttp/internal/mime"
 	"github.com/Mrs4s/go-cqhttp/internal/param"
 )
@@ -895,9 +896,9 @@ func (bot *CQBot) ToElement(t string, d map[string]string, sourceType message.So
 			name := info.Get("track_info.name").Str
 			mid := info.Get("track_info.mid").Str
 			albumMid := info.Get("track_info.album.mid").Str
-			pinfo, _ := global.GetBytes("http://u.y.qq.com/cgi-bin/musicu.fcg?g_tk=2034008533&uin=0&format=json&data={\"comm\":{\"ct\":23,\"cv\":0},\"url_mid\":{\"module\":\"vkey.GetVkeyServer\",\"method\":\"CgiGetVkey\",\"param\":{\"guid\":\"4311206557\",\"songmid\":[\"" + mid + "\"],\"songtype\":[0],\"uin\":\"0\",\"loginflag\":1,\"platform\":\"23\"}}}&_=1599039471576")
+			pinfo, _ := download.Request{URL: "http://u.y.qq.com/cgi-bin/musicu.fcg?g_tk=2034008533&uin=0&format=json&data={\"comm\":{\"ct\":23,\"cv\":0},\"url_mid\":{\"module\":\"vkey.GetVkeyServer\",\"method\":\"CgiGetVkey\",\"param\":{\"guid\":\"4311206557\",\"songmid\":[\"" + mid + "\"],\"songtype\":[0],\"uin\":\"0\",\"loginflag\":1,\"platform\":\"23\"}}}&_=1599039471576"}.JSON()
 			jumpURL := "https://i.y.qq.com/v8/playsong.html?platform=11&appshare=android_qq&appversion=10030010&hosteuin=oKnlNenz7i-s7c**&songmid=" + mid + "&type=0&appsongtype=1&_wv=1&source=qq&ADTAG=qfshare"
-			purl := gjson.ParseBytes(pinfo).Get("url_mid.data.midurlinfo.0.purl").Str
+			purl := pinfo.Get("url_mid.data.midurlinfo.0.purl").Str
 			preview := "http://y.gtimg.cn/music/photo_new/T002R180x180M000" + albumMid + ".jpg"
 			content := info.Get("track_info.singer.0.name").Str
 			if d["content"] != "" {
@@ -1089,8 +1090,11 @@ func (bot *CQBot) makeImageOrVideoElem(d map[string]string, video bool, sourceTy
 		if exist {
 			_ = os.Remove(cacheFile)
 		}
-		if err := global.DownloadFileMultiThreading(f, cacheFile, maxSize, thread, nil); err != nil {
-			return nil, err
+		{
+			r := download.Request{URL: f, Limit: maxSize}
+			if err := r.WriteToFileMultiThreading(cacheFile, thread); err != nil {
+				return nil, err
+			}
 		}
 	useCacheFile:
 		if video {

coolq/event.go

@@ -4,7 +4,6 @@ import (
 	"encoding/hex"
 	"encoding/json"
 	"fmt"
-	"os"
 	"path"
 	"strconv"
 	"strings"
@@ -18,6 +17,7 @@ import (
 	"github.com/Mrs4s/go-cqhttp/global"
 	"github.com/Mrs4s/go-cqhttp/internal/base"
 	"github.com/Mrs4s/go-cqhttp/internal/cache"
+	"github.com/Mrs4s/go-cqhttp/internal/download"
 )
 
 // ToFormattedMessage 将给定[]message.IMessageElement转换为通过coolq.SetMessageFormat所定义的消息上报格式
@@ -666,7 +666,8 @@ func (bot *CQBot) checkMedia(e []message.IMessageElement, sourceID int64) {
 			filename := hex.EncodeToString(i.Md5) + ".image"
 			cache.Image.Insert(i.Md5, data)
 			if i.Url != "" && !global.PathExists(path.Join(global.ImagePath, "guild-images", filename)) {
-				if err := global.DownloadFile(i.Url, path.Join(global.ImagePath, "guild-images", filename), -1, nil); err != nil {
+				r := download.Request{URL: i.Url}
+				if err := r.WriteToFile(path.Join(global.ImagePath, "guild-images", filename)); err != nil {
 					log.Warnf("下载频道图片时出现错误: %v", err)
 				}
 			}
@@ -684,12 +685,11 @@ func (bot *CQBot) checkMedia(e []message.IMessageElement, sourceID int64) {
 			i.Name = strings.ReplaceAll(i.Name, "{", "")
 			i.Name = strings.ReplaceAll(i.Name, "}", "")
 			if !global.PathExists(path.Join(global.VoicePath, i.Name)) {
-				b, err := global.GetBytes(i.Url)
+				err := download.Request{URL: i.Url}.WriteToFile(path.Join(global.VoicePath, i.Name))
 				if err != nil {
 					log.Warnf("语音文件 %v 下载失败: %v", i.Name, err)
 					continue
 				}
-				_ = os.WriteFile(path.Join(global.VoicePath, i.Name), b, 0o644)
 			}
 		case *message.ShortVideoElement:
 			data := binary.NewWriterF(func(w *binary.Writer) {

global/fs.go

@@ -16,6 +16,8 @@ import (
 	b14 "github.com/fumiama/go-base16384"
 	"github.com/segmentio/asm/base64"
 	log "github.com/sirupsen/logrus"
+
+	"github.com/Mrs4s/go-cqhttp/internal/download"
 )
 
 const (
@@ -82,8 +84,7 @@ func FindFile(file, cache, p string) (data []byte, err error) {
 		if (cache == "" || cache == "1") && PathExists(cacheFile) {
 			return os.ReadFile(cacheFile)
 		}
-		data, err = GetBytes(file)
-		_ = os.WriteFile(cacheFile, data, 0o644)
+		err = download.Request{URL: file}.WriteToFile(cacheFile)
 		if err != nil {
 			return nil, err
 		}

global/net.go

@@ -1,304 +1,27 @@
 package global
 
 import (
-	"bufio"
-	"compress/gzip"
 	"fmt"
-	"io"
-	"net/http"
-	"net/url"
-	"os"
-	"strconv"
-	"strings"
-	"sync"
-
-	"github.com/pkg/errors"
 
 	"github.com/tidwall/gjson"
 
-	"github.com/Mrs4s/go-cqhttp/internal/base"
+	"github.com/Mrs4s/go-cqhttp/internal/download"
 )
 
-var (
-	client = &http.Client{
-		Transport: &http.Transport{
-			Proxy: func(request *http.Request) (u *url.URL, e error) {
-				if base.Proxy == "" {
-					return http.ProxyFromEnvironment(request)
-				}
-				return url.Parse(base.Proxy)
-			},
-			ForceAttemptHTTP2:   true,
-			MaxConnsPerHost:     0,
-			MaxIdleConns:        0,
-			MaxIdleConnsPerHost: 999,
-		},
-	}
-
-	// ErrOverSize 响应主体过大时返回此错误
-	ErrOverSize = errors.New("oversize")
-
-	// UserAgent HTTP请求时使用的UA
-	UserAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.66"
-)
-
-// GetBytes 对给定URL发送Get请求，返回响应主体
-func GetBytes(url string) ([]byte, error) {
-	reader, err := HTTPGetReadCloser(url)
-	if err != nil {
-		return nil, err
-	}
-	defer func() {
-		_ = reader.Close()
-	}()
-	return io.ReadAll(reader)
-}
-
-// DownloadFile 将给定URL对应的文件下载至给定Path
-func DownloadFile(url, path string, limit int64, headers map[string]string) error {
-	file, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE, 0o666)
-	if err != nil {
-		return err
-	}
-	defer file.Close()
-	req, err := http.NewRequest(http.MethodGet, url, nil)
-	if err != nil {
-		return err
-	}
-
-	for k, v := range headers {
-		req.Header.Set(k, v)
-	}
-
-	resp, err := client.Do(req)
-	if err != nil {
-		return err
-	}
-	defer resp.Body.Close()
-	if limit > 0 && resp.ContentLength > limit {
-		return ErrOverSize
-	}
-	_, err = file.ReadFrom(resp.Body)
-	if err != nil {
-		return err
-	}
-	return nil
-}
-
-// DownloadFileMultiThreading 使用threadCount个线程将给定URL对应的文件下载至给定Path
-func DownloadFileMultiThreading(url, path string, limit int64, threadCount int, headers map[string]string) error {
-	if threadCount < 2 {
-		return DownloadFile(url, path, limit, headers)
-	}
-	type BlockMetaData struct {
-		BeginOffset    int64
-		EndOffset      int64
-		DownloadedSize int64
-	}
-	var blocks []*BlockMetaData
-	var contentLength int64
-	errUnsupportedMultiThreading := errors.New("unsupported multi-threading")
-	// 初始化分块或直接下载
-	initOrDownload := func() error {
-		copyStream := func(s io.ReadCloser) error {
-			file, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE, 0o666)
-			if err != nil {
-				return err
-			}
-			defer file.Close()
-			if _, err = file.ReadFrom(s); err != nil {
-				return err
-			}
-			return errUnsupportedMultiThreading
-		}
-		req, err := http.NewRequest(http.MethodGet, url, nil)
-		if err != nil {
-			return err
-		}
-
-		for k, v := range headers {
-			req.Header.Set(k, v)
-		}
-		if _, ok := headers["User-Agent"]; !ok {
-			req.Header["User-Agent"] = []string{UserAgent}
-		}
-		req.Header.Set("range", "bytes=0-")
-		resp, err := client.Do(req)
-		if err != nil {
-			return err
-		}
-		defer resp.Body.Close()
-		if resp.StatusCode < 200 || resp.StatusCode >= 300 {
-			return errors.New("response status unsuccessful: " + strconv.FormatInt(int64(resp.StatusCode), 10))
-		}
-		if resp.StatusCode == http.StatusOK {
-			if limit > 0 && resp.ContentLength > limit {
-				return ErrOverSize
-			}
-			return copyStream(resp.Body)
-		}
-		if resp.StatusCode == http.StatusPartialContent {
-			contentLength = resp.ContentLength
-			if limit > 0 && resp.ContentLength > limit {
-				return ErrOverSize
-			}
-			blockSize := contentLength
-			if contentLength > 1024*1024 {
-				blockSize = (contentLength / int64(threadCount)) - 10
-			}
-			if blockSize == contentLength {
-				return copyStream(resp.Body)
-			}
-			var tmp int64
-			for tmp+blockSize < contentLength {
-				blocks = append(blocks, &BlockMetaData{
-					BeginOffset: tmp,
-					EndOffset:   tmp + blockSize - 1,
-				})
-				tmp += blockSize
-			}
-			blocks = append(blocks, &BlockMetaData{
-				BeginOffset: tmp,
-				EndOffset:   contentLength - 1,
-			})
-			return nil
-		}
-		return errors.New("unknown status code")
-	}
-	// 下载分块
-	downloadBlock := func(block *BlockMetaData) error {
-		req, _ := http.NewRequest(http.MethodGet, url, nil)
-		file, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE, 0o666)
-		if err != nil {
-			return err
-		}
-		defer file.Close()
-		_, _ = file.Seek(block.BeginOffset, io.SeekStart)
-		writer := bufio.NewWriter(file)
-		defer writer.Flush()
-
-		for k, v := range headers {
-			req.Header.Set(k, v)
-		}
-
-		if _, ok := headers["User-Agent"]; !ok {
-			req.Header["User-Agent"] = []string{UserAgent}
-		}
-		req.Header.Set("range", "bytes="+strconv.FormatInt(block.BeginOffset, 10)+"-"+strconv.FormatInt(block.EndOffset, 10))
-		resp, err := client.Do(req)
-		if err != nil {
-			return err
-		}
-		defer resp.Body.Close()
-		if resp.StatusCode < 200 || resp.StatusCode >= 300 {
-			return errors.New("response status unsuccessful: " + strconv.FormatInt(int64(resp.StatusCode), 10))
-		}
-		buffer := make([]byte, 1024)
-		i, err := resp.Body.Read(buffer)
-		for {
-			if err != nil && err != io.EOF {
-				return err
-			}
-			i64 := int64(len(buffer[:i]))
-			needSize := block.EndOffset + 1 - block.BeginOffset
-			if i64 > needSize {
-				i64 = needSize
-				err = io.EOF
-			}
-			_, e := writer.Write(buffer[:i64])
-			if e != nil {
-				return e
-			}
-			block.BeginOffset += i64
-			block.DownloadedSize += i64
-			if err == io.EOF || block.BeginOffset > block.EndOffset {
-				break
-			}
-			i, err = resp.Body.Read(buffer)
-		}
-		return nil
-	}
-
-	if err := initOrDownload(); err != nil {
-		if err == errUnsupportedMultiThreading {
-			return nil
-		}
-		return err
-	}
-	wg := sync.WaitGroup{}
-	wg.Add(len(blocks))
-	var lastErr error
-	for i := range blocks {
-		go func(b *BlockMetaData) {
-			defer wg.Done()
-			if err := downloadBlock(b); err != nil {
-				lastErr = err
-			}
-		}(blocks[i])
-	}
-	wg.Wait()
-	return lastErr
-}
-
 // QQMusicSongInfo 通过给定id在QQ音乐上查找曲目信息
 func QQMusicSongInfo(id string) (gjson.Result, error) {
-	d, err := GetBytes(`https://u.y.qq.com/cgi-bin/musicu.fcg?format=json&inCharset=utf8&outCharset=utf-8&notice=0&platform=yqq.json&needNewCode=0&data={%22comm%22:{%22ct%22:24,%22cv%22:0},%22songinfo%22:{%22method%22:%22get_song_detail_yqq%22,%22param%22:{%22song_type%22:0,%22song_mid%22:%22%22,%22song_id%22:` + id + `},%22module%22:%22music.pf_song_detail_svr%22}}`)
+	d, err := download.Request{URL: `https://u.y.qq.com/cgi-bin/musicu.fcg?format=json&inCharset=utf8&outCharset=utf-8&notice=0&platform=yqq.json&needNewCode=0&data={%22comm%22:{%22ct%22:24,%22cv%22:0},%22songinfo%22:{%22method%22:%22get_song_detail_yqq%22,%22param%22:{%22song_type%22:0,%22song_mid%22:%22%22,%22song_id%22:` + id + `},%22module%22:%22music.pf_song_detail_svr%22}}`}.JSON()
 	if err != nil {
 		return gjson.Result{}, err
 	}
-	return gjson.ParseBytes(d).Get("songinfo.data"), nil
+	return d.Get("songinfo.data"), nil
 }
 
 // NeteaseMusicSongInfo 通过给定id在wdd音乐上查找曲目信息
 func NeteaseMusicSongInfo(id string) (gjson.Result, error) {
-	d, err := GetBytes(fmt.Sprintf("http://music.163.com/api/song/detail/?id=%s&ids=%%5B%s%%5D", id, id))
+	d, err := download.Request{URL: fmt.Sprintf("http://music.163.com/api/song/detail/?id=%s&ids=%%5B%s%%5D", id, id)}.JSON()
 	if err != nil {
 		return gjson.Result{}, err
 	}
-	return gjson.ParseBytes(d).Get("songs.0"), nil
-}
-
-type gzipCloser struct {
-	f io.Closer
-	r *gzip.Reader
-}
-
-// NewGzipReadCloser 从 io.ReadCloser 创建 gunzip io.ReadCloser
-func NewGzipReadCloser(reader io.ReadCloser) (io.ReadCloser, error) {
-	gzipReader, err := gzip.NewReader(reader)
-	if err != nil {
-		return nil, err
-	}
-	return &gzipCloser{
-		f: reader,
-		r: gzipReader,
-	}, nil
-}
-
-// Read impls io.Reader
-func (g *gzipCloser) Read(p []byte) (n int, err error) {
-	return g.r.Read(p)
-}
-
-// Close impls io.Closer
-func (g *gzipCloser) Close() error {
-	_ = g.f.Close()
-	return g.r.Close()
-}
-
-// HTTPGetReadCloser 从 Http url 获取 io.ReadCloser
-func HTTPGetReadCloser(url string) (io.ReadCloser, error) {
-	req, err := http.NewRequest(http.MethodGet, url, nil)
-	if err != nil {
-		return nil, err
-	}
-	req.Header["User-Agent"] = []string{UserAgent}
-	resp, err := client.Do(req)
-	if err != nil {
-		return nil, err
-	}
-	if strings.Contains(resp.Header.Get("Content-Encoding"), "gzip") {
-		return NewGzipReadCloser(resp.Body)
-	}
-	return resp.Body, err
+	return d.Get("songs.0"), nil
 }

internal/download/download.go

@@ -0,0 +1,295 @@
+package download
+
+import (
+	"bufio"
+	"compress/gzip"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+
+	"github.com/pkg/errors"
+	"github.com/tidwall/gjson"
+
+	"github.com/Mrs4s/go-cqhttp/internal/base"
+)
+
+var client = &http.Client{
+	Transport: &http.Transport{
+		Proxy: func(request *http.Request) (u *url.URL, e error) {
+			if base.Proxy == "" {
+				return http.ProxyFromEnvironment(request)
+			}
+			return url.Parse(base.Proxy)
+		},
+		ForceAttemptHTTP2:   false,
+		MaxConnsPerHost:     0,
+		MaxIdleConns:        0,
+		MaxIdleConnsPerHost: 999,
+	},
+}
+
+// ErrOverSize 响应主体过大时返回此错误
+var ErrOverSize = errors.New("oversize")
+
+// UserAgent HTTP请求时使用的UA
+const UserAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36 Edg/87.0.664.66"
+
+type Request struct {
+	URL    string
+	Header map[string]string
+	Limit  int64
+}
+
+func (r Request) do() (*http.Response, error) {
+	req, err := http.NewRequest(http.MethodGet, r.URL, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header["User-Agent"] = []string{UserAgent}
+	for k, v := range r.Header {
+		req.Header.Set(k, v)
+	}
+
+	return client.Do(req)
+}
+
+func (r Request) body() (io.ReadCloser, error) {
+	resp, err := r.do()
+	if err != nil {
+		return nil, err
+	}
+
+	limit := r.Limit // check file size limit
+	if limit > 0 && resp.ContentLength > limit {
+		_ = resp.Body.Close()
+		return nil, ErrOverSize
+	}
+
+	if strings.Contains(resp.Header.Get("Content-Encoding"), "gzip") {
+		return gzipReadCloser(resp.Body)
+	}
+	return resp.Body, err
+}
+
+// Bytes 对给定URL发送Get请求，返回响应主体
+func (r Request) Bytes() ([]byte, error) {
+	rd, err := r.body()
+	if err != nil {
+		return nil, err
+	}
+	defer rd.Close()
+	return io.ReadAll(rd)
+}
+
+func (r Request) JSON() (gjson.Result, error) {
+	rd, err := r.body()
+	if err != nil {
+		return gjson.Result{}, err
+	}
+	defer rd.Close()
+
+	var sb strings.Builder
+	_, err = io.Copy(&sb, rd)
+	if err != nil {
+		return gjson.Result{}, err
+	}
+
+	return gjson.Parse(sb.String()), nil
+}
+
+func writeToFile(reader io.ReadCloser, path string) error {
+	file, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE, 0o644)
+	if err != nil {
+		return err
+	}
+	_, err = file.ReadFrom(reader)
+	return err
+}
+
+func (r Request) WriteToFile(path string) error {
+	rd, err := r.body()
+	if err != nil {
+		return err
+	}
+	defer rd.Close()
+	return writeToFile(rd, path)
+}
+
+func (r Request) WriteToFileMultiThreading(path string, thread int) error {
+	if thread < 2 {
+		return r.WriteToFile(path)
+	}
+
+	limit := r.Limit
+	type BlockMetaData struct {
+		BeginOffset    int64
+		EndOffset      int64
+		DownloadedSize int64
+	}
+	var blocks []*BlockMetaData
+	var contentLength int64
+	errUnsupportedMultiThreading := errors.New("unsupported multi-threading")
+	// 初始化分块或直接下载
+	initOrDownload := func() error {
+		header := make(map[string]string, len(r.Header))
+		for k, v := range r.Header { // copy headers
+			header[k] = v
+		}
+		header["range"] = "bytes=0-"
+		req := Request{
+			URL:    r.URL,
+			Header: header,
+		}
+		resp, err := req.do()
+		if err != nil {
+			return err
+		}
+		defer resp.Body.Close()
+		if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+			return errors.New("response status unsuccessful: " + strconv.FormatInt(int64(resp.StatusCode), 10))
+		}
+		if resp.StatusCode == http.StatusOK {
+			if limit > 0 && resp.ContentLength > limit {
+				return ErrOverSize
+			}
+			if err = writeToFile(resp.Body, path); err != nil {
+				return err
+			}
+			return errUnsupportedMultiThreading
+		}
+		if resp.StatusCode == http.StatusPartialContent {
+			contentLength = resp.ContentLength
+			if limit > 0 && resp.ContentLength > limit {
+				return ErrOverSize
+			}
+			blockSize := contentLength
+			if contentLength > 1024*1024 {
+				blockSize = (contentLength / int64(thread)) - 10
+			}
+			if blockSize == contentLength {
+				return writeToFile(resp.Body, path)
+			}
+			var tmp int64
+			for tmp+blockSize < contentLength {
+				blocks = append(blocks, &BlockMetaData{
+					BeginOffset: tmp,
+					EndOffset:   tmp + blockSize - 1,
+				})
+				tmp += blockSize
+			}
+			blocks = append(blocks, &BlockMetaData{
+				BeginOffset: tmp,
+				EndOffset:   contentLength - 1,
+			})
+			return nil
+		}
+		return errors.New("unknown status code")
+	}
+	// 下载分块
+	downloadBlock := func(block *BlockMetaData) error {
+		file, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE, 0o666)
+		if err != nil {
+			return err
+		}
+		defer file.Close()
+		_, _ = file.Seek(block.BeginOffset, io.SeekStart)
+		writer := bufio.NewWriter(file)
+		defer writer.Flush()
+
+		header := make(map[string]string, len(r.Header))
+		for k, v := range r.Header { // copy headers
+			header[k] = v
+		}
+		header["range"] = fmt.Sprintf("bytes=%d-%d", block.BeginOffset, block.EndOffset)
+		req := Request{
+			URL:    r.URL,
+			Header: header,
+		}
+		resp, err := req.do()
+		if err != nil {
+			return err
+		}
+		defer resp.Body.Close()
+		if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+			return errors.New("response status unsuccessful: " + strconv.FormatInt(int64(resp.StatusCode), 10))
+		}
+		buffer := make([]byte, 1024)
+		i, err := resp.Body.Read(buffer)
+		for {
+			if err != nil && err != io.EOF {
+				return err
+			}
+			i64 := int64(len(buffer[:i]))
+			needSize := block.EndOffset + 1 - block.BeginOffset
+			if i64 > needSize {
+				i64 = needSize
+				err = io.EOF
+			}
+			_, e := writer.Write(buffer[:i64])
+			if e != nil {
+				return e
+			}
+			block.BeginOffset += i64
+			block.DownloadedSize += i64
+			if err == io.EOF || block.BeginOffset > block.EndOffset {
+				break
+			}
+			i, err = resp.Body.Read(buffer)
+		}
+		return nil
+	}
+
+	if err := initOrDownload(); err != nil {
+		if err == errUnsupportedMultiThreading {
+			return nil
+		}
+		return err
+	}
+	wg := sync.WaitGroup{}
+	wg.Add(len(blocks))
+	var lastErr error
+	for i := range blocks {
+		go func(b *BlockMetaData) {
+			defer wg.Done()
+			if err := downloadBlock(b); err != nil {
+				lastErr = err
+			}
+		}(blocks[i])
+	}
+	wg.Wait()
+	return lastErr
+}
+
+type gzipCloser struct {
+	f io.Closer
+	r *gzip.Reader
+}
+
+// gzipReadCloser 从 io.ReadCloser 创建 gunzip io.ReadCloser
+func gzipReadCloser(reader io.ReadCloser) (io.ReadCloser, error) {
+	gzipReader, err := gzip.NewReader(reader)
+	if err != nil {
+		return nil, err
+	}
+	return &gzipCloser{
+		f: reader,
+		r: gzipReader,
+	}, nil
+}
+
+// Read impls io.Reader
+func (g *gzipCloser) Read(p []byte) (n int, err error) {
+	return g.r.Read(p)
+}
+
+// Close impls io.Closer
+func (g *gzipCloser) Close() error {
+	_ = g.f.Close()
+	return g.r.Close()
+}

internal/selfupdate/update.go

@@ -3,6 +3,7 @@ package selfupdate
 
 import (
 	"bufio"
+	"bytes"
 	"encoding/hex"
 	"fmt"
 	"hash"
@@ -14,10 +15,10 @@ import (
 	"strings"
 
 	"github.com/sirupsen/logrus"
-	"github.com/tidwall/gjson"
 
 	"github.com/Mrs4s/go-cqhttp/global"
 	"github.com/Mrs4s/go-cqhttp/internal/base"
+	"github.com/Mrs4s/go-cqhttp/internal/download"
 )
 
 func readLine() (str string) {
@@ -28,11 +29,11 @@ func readLine() (str string) {
 }
 
 func lastVersion() (string, error) {
-	r, err := global.GetBytes("https://api.github.com/repos/Mrs4s/go-cqhttp/releases/latest")
+	r, err := download.Request{URL: "https://api.github.com/repos/Mrs4s/go-cqhttp/releases/latest"}.JSON()
 	if err != nil {
 		return "", err
 	}
-	return gjson.GetBytes(r, "tag_name").Str, nil
+	return r.Get("tag_name").Str, nil
 }
 
 // CheckUpdate 检查更新
@@ -69,12 +70,12 @@ func binaryName() string {
 
 func checksum(github, version string) []byte {
 	sumURL := fmt.Sprintf("%v/Mrs4s/go-cqhttp/releases/download/%v/go-cqhttp_checksums.txt", github, version)
-	closer, err := global.HTTPGetReadCloser(sumURL)
+	sum, err := download.Request{URL: sumURL}.Bytes()
 	if err != nil {
 		return nil
 	}
 
-	rd := bufio.NewReader(closer)
+	rd := bufio.NewReader(bytes.NewReader(sum))
 	for {
 		str, err := rd.ReadString('\n')
 		if err != nil {