Initial release of bdrclone

internal/baidu/files.go

@@ -0,0 +1,186 @@
+package baidu
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"path"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var ErrNotFound = errors.New("remote path not found")
+
+func (c *Client) List(ctx context.Context, name string) ([]File, error) {
+	remote := c.RemotePath(name)
+	var result []File
+	for start := 0; ; start += 1000 {
+		var response struct {
+			List []File `json:"list"`
+		}
+		q := url.Values{
+			"method": {"list"}, "dir": {remote}, "start": {strconv.Itoa(start)},
+			"limit": {"1000"}, "order": {"name"},
+		}
+		if err := c.request(ctx, http.MethodGet, c.xpanFile(), q, nil, &response); err != nil {
+			return nil, err
+		}
+		result = append(result, response.List...)
+		if len(response.List) < 1000 {
+			return result, nil
+		}
+	}
+}
+
+func (c *Client) Stat(ctx context.Context, name string) (File, error) {
+	remote := c.RemotePath(name)
+	if remote == c.root || (c.root == "/" && remote == "/") {
+		return File{Path: remote, ServerFilename: path.Base(remote), IsDir: 1}, nil
+	}
+	parent := path.Dir(c.APIPath(remote))
+	entries, err := c.List(ctx, parent)
+	if err != nil {
+		return File{}, err
+	}
+	for _, entry := range entries {
+		if entry.Path == remote || entry.Name() == path.Base(remote) {
+			return entry, nil
+		}
+	}
+	return File{}, fmt.Errorf("%w: %s", ErrNotFound, name)
+}
+
+func (c *Client) Mkdir(ctx context.Context, name string) (File, error) {
+	form := url.Values{
+		"path": {c.RemotePath(name)}, "size": {"0"}, "isdir": {"1"}, "rtype": {"3"},
+	}
+	var result File
+	if err := c.request(ctx, http.MethodPost, c.xpanFile(), url.Values{"method": {"create"}}, form, &result); err != nil {
+		return File{}, err
+	}
+	return result, nil
+}
+
+func (c *Client) Delete(ctx context.Context, name string) error {
+	remote := c.RemotePath(name)
+	if remote == c.root {
+		return errors.New("refusing to delete the configured remote root")
+	}
+	paths, _ := json.Marshal([]string{remote})
+	return c.manage(ctx, "delete", string(paths))
+}
+
+func (c *Client) Move(ctx context.Context, source, destination string) error {
+	src := c.RemotePath(source)
+	if src == c.root {
+		return errors.New("refusing to move the configured remote root")
+	}
+	dst := c.RemotePath(destination)
+	items := []map[string]string{{"path": src, "dest": path.Dir(dst), "newname": path.Base(dst)}}
+	b, _ := json.Marshal(items)
+	return c.manage(ctx, "move", string(b))
+}
+
+func (c *Client) Copy(ctx context.Context, source, destination string) error {
+	src := c.RemotePath(source)
+	dst := c.RemotePath(destination)
+	items := []map[string]string{{"path": src, "dest": path.Dir(dst), "newname": path.Base(dst)}}
+	b, _ := json.Marshal(items)
+	return c.manage(ctx, "copy", string(b))
+}
+
+func (c *Client) manage(ctx context.Context, operation, fileList string) error {
+	q := url.Values{"method": {"filemanager"}, "opera": {operation}}
+	form := url.Values{"async": {"0"}, "ondup": {"fail"}, "filelist": {fileList}}
+	return c.request(ctx, http.MethodPost, c.xpanFile(), q, form, nil)
+}
+
+func (c *Client) Quota(ctx context.Context) (Quota, error) {
+	var result Quota
+	err := c.request(ctx, http.MethodGet, c.apiBase+"/api/quota", nil, nil, &result)
+	return result, err
+}
+
+func (c *Client) DownloadURL(ctx context.Context, file File) (string, error) {
+	if file.FSID == 0 {
+		return "", errors.New("file has no fs_id")
+	}
+	c.downloadMu.Lock()
+	cached, ok := c.downloadURL[file.FSID]
+	c.downloadMu.Unlock()
+	if ok && time.Now().Before(cached.expiresAt) {
+		return cached.url, nil
+	}
+	ids, _ := json.Marshal([]int64{file.FSID})
+	var response struct {
+		List []File `json:"list"`
+	}
+	q := url.Values{"method": {"filemetas"}, "fsids": {string(ids)}, "dlink": {"1"}}
+	if err := c.request(ctx, http.MethodGet, c.xpanMultimedia(), q, nil, &response); err != nil {
+		return "", err
+	}
+	if len(response.List) == 0 || response.List[0].DLink == "" {
+		return "", errors.New("Baidu returned no download URL")
+	}
+	u, err := url.Parse(response.List[0].DLink)
+	if err != nil {
+		return "", fmt.Errorf("parse download URL: %w", err)
+	}
+	q2 := u.Query()
+	q2.Set("access_token", c.token())
+	u.RawQuery = q2.Encode()
+	result := u.String()
+	c.downloadMu.Lock()
+	c.downloadURL[file.FSID] = cachedDownloadURL{url: result, expiresAt: time.Now().Add(50 * time.Minute)}
+	c.downloadMu.Unlock()
+	return result, nil
+}
+
+func (c *Client) Open(ctx context.Context, file File, offset, length int64) (io.ReadCloser, error) {
+	for attempt := 0; attempt < 2; attempt++ {
+		downloadURL, err := c.DownloadURL(ctx, file)
+		if err != nil {
+			return nil, err
+		}
+		req, err := http.NewRequestWithContext(ctx, http.MethodGet, downloadURL, nil)
+		if err != nil {
+			return nil, err
+		}
+		req.Header.Set("User-Agent", c.userAgent)
+		if offset > 0 || length > 0 {
+			end := ""
+			if length > 0 {
+				end = strconv.FormatInt(offset+length-1, 10)
+			}
+			req.Header.Set("Range", "bytes="+strconv.FormatInt(offset, 10)+"-"+end)
+		}
+		resp, err := c.httpClient.Do(req)
+		if err != nil {
+			return nil, fmt.Errorf("download %s: %w", file.Path, err)
+		}
+		if resp.StatusCode == http.StatusOK || resp.StatusCode == http.StatusPartialContent {
+			if resp.StatusCode == http.StatusOK && offset > 0 {
+				if _, err := io.CopyN(io.Discard, resp.Body, offset); err != nil {
+					resp.Body.Close()
+					return nil, fmt.Errorf("seek download %s to %d: %w", file.Path, offset, err)
+				}
+			}
+			return resp.Body, nil
+		}
+		b, _ := io.ReadAll(io.LimitReader(resp.Body, 64<<10))
+		resp.Body.Close()
+		if attempt == 0 && (resp.StatusCode == http.StatusForbidden || resp.StatusCode == http.StatusUnauthorized || resp.StatusCode == http.StatusNotFound) {
+			c.downloadMu.Lock()
+			delete(c.downloadURL, file.FSID)
+			c.downloadMu.Unlock()
+			continue
+		}
+		return nil, fmt.Errorf("download %s: HTTP %s: %s", file.Path, resp.Status, strings.TrimSpace(string(b)))
+	}
+	return nil, fmt.Errorf("download %s failed after refreshing its temporary URL", file.Path)
+}