Fix uploading files to NextCloud via WebDAV (#4420)

The HTTP request to NextCloud was made with Transfer-Encoding: chunked,
because of the way the Content-Length was set. But it looks like
NextCloud doesn't support that, and files were created empty. We can
avoid that by setting request.ContentLength.

docs/nextcloud.md

@@ -264,7 +264,8 @@ HTTP/1.1 204 No Content
 
 This route can be used to create a copy of a file in the same directory, with a
 copy suffix in its name. The new name can be optionaly given with the `Name`
-parameter in the query-string.
+parameter in the query-string, or the full path can be given with `Path`
+parameter.
 
 The `:account` parameter is the identifier of the NextCloud `io.cozy.account`.
 
@@ -275,7 +276,7 @@ The `*path` parameter is the path of the file on the NextCloud.
 ### Request
 
 ```http
-POST /remote/nextcloud/4ab2155707bb6613a8b9463daf00381b/copy/Documents/wallpaper.jpg HTTP/1.1
+POST /remote/nextcloud/4ab2155707bb6613a8b9463daf00381b/copy/Documents/wallpaper.jpg?Path=/Images/beach.jpg HTTP/1.1
 Host: cozy.example.net
 Authorization: Bearer eyJhbG...
 ```
@@ -303,7 +304,7 @@ Content-Type: application/json
 
 ## POST /remote/nextcloud/:account/downstream/*path
 
-This route can be used to move a file from the NextCloud to the Cozy.
+This route can be used to move/copy a file from the NextCloud to the Cozy.
 
 The `:account` parameter is the identifier of the NextCloud `io.cozy.account`.
 
@@ -312,6 +313,9 @@ The `*path` parameter is the path of the file on the NextCloud.
 The `To` parameter in the query-string must be given, as the ID of the
 directory on the Cozy where the file will be put.
 
+By default, the file will be moved, but using `Copy=true` in the query-string
+will makes a copy.
+
 **Note:** a permission on `POST io.cozy.files` is required to use this route.
 
 ### Request
@@ -392,7 +396,7 @@ Content-Type: application/vnd.api+json
 
 ## POST /remote/nextcloud/:account/upstream/*path
 
-This route can be used to move a file from the Cozy to the NextCloud.
+This route can be used to move/copy a file from the Cozy to the NextCloud.
 
 The `:account` parameter is the identifier of the NextCloud `io.cozy.account`.
 
@@ -401,6 +405,9 @@ The `*path` parameter is the path of the file on the NextCloud.
 The `From` parameter in the query-string must be given, as the ID of the
 file on the Cozy that will be moved.
 
+By default, the file will be moved, but using `Copy=true` in the query-string
+will makes a copy.
+
 **Note:** a permission on `POST io.cozy.files` is required to use this route.
 
 ### Request

model/nextcloud/nextcloud.go

@@ -24,6 +24,13 @@ import (
 	"github.com/labstack/echo/v4"
 )
 
+type OperationKind int
+
+const (
+	MoveOperation OperationKind = iota
+	CopyOperation
+)
+
 type File struct {
 	DocID     string `json:"id,omitempty"`
 	Type      string `json:"type"`
@@ -109,11 +116,11 @@ func (nc *NextCloud) Download(path string) (*webdav.Download, error) {
 	return nc.webdav.Get(path)
 }
 
-func (nc *NextCloud) Upload(path, mime string, body io.Reader) error {
+func (nc *NextCloud) Upload(path, mime string, contentLength int64, body io.Reader) error {
 	headers := map[string]string{
 		echo.HeaderContentType: mime,
 	}
-	return nc.webdav.Put(path, headers, body)
+	return nc.webdav.Put(path, contentLength, headers, body)
 }
 
 func (nc *NextCloud) Mkdir(path string) error {
@@ -160,7 +167,7 @@ func (nc *NextCloud) ListFiles(path string) ([]jsonapi.Object, error) {
 	return files, nil
 }
 
-func (nc *NextCloud) Downstream(path, dirID string, cozyMetadata *vfs.FilesCozyMetadata) (*vfs.FileDoc, error) {
+func (nc *NextCloud) Downstream(path, dirID string, kind OperationKind, cozyMetadata *vfs.FilesCozyMetadata) (*vfs.FileDoc, error) {
 	dl, err := nc.webdav.Get(path)
 	if err != nil {
 		return nil, err
@@ -201,11 +208,13 @@ func (nc *NextCloud) Downstream(path, dirID string, cozyMetadata *vfs.FilesCozyM
 		return nil, err
 	}
 
-	_ = nc.webdav.Delete(path)
+	if kind == MoveOperation {
+		_ = nc.webdav.Delete(path)
+	}
 	return doc, nil
 }
 
-func (nc *NextCloud) Upstream(path, from string) error {
+func (nc *NextCloud) Upstream(path, from string, kind OperationKind) error {
 	fs := nc.inst.VFS()
 	doc, err := fs.FileByID(from)
 	if err != nil {
@@ -218,13 +227,14 @@ func (nc *NextCloud) Upstream(path, from string) error {
 	defer f.Close()
 
 	headers := map[string]string{
-		echo.HeaderContentType:   doc.Mime,
-		echo.HeaderContentLength: strconv.Itoa(int(doc.ByteSize)),
+		echo.HeaderContentType: doc.Mime,
 	}
-	if err := nc.webdav.Put(path, headers, f); err != nil {
+	if err := nc.webdav.Put(path, doc.ByteSize, headers, f); err != nil {
 		return err
 	}
-	_ = fs.DestroyFile(doc)
+	if kind == MoveOperation {
+		_ = fs.DestroyFile(doc)
+	}
 	return nil
 }
 

pkg/webdav/webdav.go

@@ -27,7 +27,7 @@ type Client struct {
 }
 
 func (c *Client) Mkcol(path string) error {
-	res, err := c.req("MKCOL", path, nil, nil)
+	res, err := c.req("MKCOL", path, 0, nil, nil)
 	if err != nil {
 		return err
 	}
@@ -47,7 +47,7 @@ func (c *Client) Mkcol(path string) error {
 }
 
 func (c *Client) Delete(path string) error {
-	res, err := c.req("DELETE", path, nil, nil)
+	res, err := c.req("DELETE", path, 0, nil, nil)
 	if err != nil {
 		return err
 	}
@@ -75,7 +75,7 @@ func (c *Client) Move(oldPath, newPath string) error {
 		"Destination": u.String(),
 		"Overwrite":   "F",
 	}
-	res, err := c.req("MOVE", oldPath, headers, nil)
+	res, err := c.req("MOVE", oldPath, 0, headers, nil)
 	if err != nil {
 		return err
 	}
@@ -105,7 +105,7 @@ func (c *Client) Copy(oldPath, newPath string) error {
 		"Destination": u.String(),
 		"Overwrite":   "F",
 	}
-	res, err := c.req("COPY", oldPath, headers, nil)
+	res, err := c.req("COPY", oldPath, 0, headers, nil)
 	if err != nil {
 		return err
 	}
@@ -124,8 +124,13 @@ func (c *Client) Copy(oldPath, newPath string) error {
 	}
 }
 
-func (c *Client) Put(path string, headers map[string]string, body io.Reader) error {
-	res, err := c.req("PUT", path, headers, body)
+func (c *Client) Put(
+	path string,
+	contentLength int64,
+	headers map[string]string,
+	body io.Reader,
+) error {
+	res, err := c.req("PUT", path, contentLength, headers, body)
 	if err != nil {
 		return err
 	}
@@ -145,7 +150,7 @@ func (c *Client) Put(path string, headers map[string]string, body io.Reader) err
 }
 
 func (c *Client) Get(path string) (*Download, error) {
-	res, err := c.req("GET", path, nil, nil)
+	res, err := c.req("GET", path, 0, nil, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -187,7 +192,7 @@ func (c *Client) List(path string) ([]Item, error) {
 		"Depth":        "1",
 	}
 	payload := strings.NewReader(ListFilesPayload)
-	res, err := c.req("PROPFIND", path, headers, payload)
+	res, err := c.req("PROPFIND", path, 0, headers, payload)
 	if err != nil {
 		return nil, err
 	}
@@ -300,7 +305,12 @@ const ListFilesPayload = `<?xml version="1.0"?>
 </d:propfind>
 `
 
-func (c *Client) req(method, path string, headers map[string]string, body io.Reader) (*http.Response, error) {
+func (c *Client) req(
+	method, path string,
+	contentLength int64,
+	headers map[string]string,
+	body io.Reader,
+) (*http.Response, error) {
 	path = c.BasePath + fixSlashes(path)
 	u := url.URL{
 		Scheme: c.Scheme,
@@ -316,6 +326,9 @@ func (c *Client) req(method, path string, headers map[string]string, body io.Rea
 	for k, v := range headers {
 		req.Header.Set(k, v)
 	}
+	if contentLength > 0 {
+		req.ContentLength = contentLength
+	}
 	start := time.Now()
 	res, err := safehttp.ClientWithKeepAlive.Do(req)
 	elapsed := time.Since(start)

web/remote/nextcloud.go

@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 
 	"github.com/cozy/cozy-stack/model/nextcloud"
@@ -103,7 +104,7 @@ func nextcloudPut(c echo.Context) error {
 func nextcloudUpload(c echo.Context, nc *nextcloud.NextCloud, path string) error {
 	req := c.Request()
 	mime := req.Header.Get(echo.HeaderContentType)
-	if err := nc.Upload(path, mime, req.Body); err != nil {
+	if err := nc.Upload(path, mime, req.ContentLength, req.Body); err != nil {
 		return wrapNextcloudErrors(err)
 	}
 	return c.JSON(http.StatusCreated, echo.Map{"ok": true})
@@ -166,7 +167,9 @@ func nextcloudCopy(c echo.Context) error {
 
 	oldPath := c.Param("*")
 	newPath := oldPath
-	if newName := c.QueryParam("Name"); newName != "" {
+	if p := c.QueryParam("Path"); p != "" {
+		newPath = p
+	} else if newName := c.QueryParam("Name"); newName != "" {
 		newPath = filepath.Join(filepath.Dir(oldPath), newName)
 	} else {
 		ext := filepath.Ext(oldPath)
@@ -199,8 +202,13 @@ func nextcloudDownstream(c echo.Context) error {
 		return jsonapi.BadRequest(errors.New("missing To parameter"))
 	}
 
+	kind := nextcloud.MoveOperation
+	if isCopy, _ := strconv.ParseBool(c.QueryParam("Copy")); isCopy {
+		kind = nextcloud.CopyOperation
+	}
+
 	cozyMetadata, _ := files.CozyMetadataFromClaims(c, true)
-	f, err := nc.Downstream(path, to, cozyMetadata)
+	f, err := nc.Downstream(path, to, kind, cozyMetadata)
 	if err != nil {
 		return wrapNextcloudErrors(err)
 	}
@@ -226,7 +234,12 @@ func nextcloudUpstream(c echo.Context) error {
 		return jsonapi.BadRequest(errors.New("missing From parameter"))
 	}
 
-	if err := nc.Upstream(path, from); err != nil {
+	kind := nextcloud.MoveOperation
+	if isCopy, _ := strconv.ParseBool(c.QueryParam("Copy")); isCopy {
+		kind = nextcloud.CopyOperation
+	}
+
+	if err := nc.Upstream(path, from, kind); err != nil {
 		return wrapNextcloudErrors(err)
 	}
 	return c.NoContent(http.StatusNoContent)