Add a new backend for uloz.to

Note that this temporarily skips uploads of files over 2.5 GB.

See https://github.com/rclone/rclone/pull/7552#issuecomment-1956316492
for details.

README.md

@@ -94,6 +94,7 @@ Rclone *("rsync for cloud storage")* is a command-line program to sync files and
   * SugarSync [:page_facing_up:](https://rclone.org/sugarsync/)
   * Synology C2 Object Storage [:page_facing_up:](https://rclone.org/s3/#synology-c2)
   * Tencent Cloud Object Storage (COS) [:page_facing_up:](https://rclone.org/s3/#tencent-cos)
+  * Uloz.to [:page_facing_up:](https://rclone.org/ulozto/)
   * Wasabi [:page_facing_up:](https://rclone.org/s3/#wasabi)
   * WebDAV [:page_facing_up:](https://rclone.org/webdav/)
   * Yandex Disk [:page_facing_up:](https://rclone.org/yandex/)

backend/all/all.go

@@ -53,6 +53,7 @@ import (
 	_ "github.com/rclone/rclone/backend/storj"
 	_ "github.com/rclone/rclone/backend/sugarsync"
 	_ "github.com/rclone/rclone/backend/swift"
+	_ "github.com/rclone/rclone/backend/ulozto"
 	_ "github.com/rclone/rclone/backend/union"
 	_ "github.com/rclone/rclone/backend/uptobox"
 	_ "github.com/rclone/rclone/backend/webdav"

backend/ulozto/api/types.go

@@ -0,0 +1,244 @@
+// Package api has type definitions for uloz.to
+package api
+
+import (
+	"errors"
+	"fmt"
+	"time"
+)
+
+// Error is a representation of the JSON structure returned by uloz.to for unsuccessful requests.
+type Error struct {
+	ErrorCode  int    `json:"error"`
+	StatusCode int    `json:"code"`
+	Message    string `json:"message"`
+}
+
+// Error implements error.Error() and returns a string representation of the error.
+func (e *Error) Error() string {
+	out := fmt.Sprintf("Error %d (%d)", e.ErrorCode, e.StatusCode)
+	if e.Message != "" {
+		out += ": " + e.Message
+	}
+	return out
+}
+
+// Is determines if the error is an instance of another error. It's required for the
+// errors package to search in causal chain.
+func (e *Error) Is(target error) bool {
+	var err *Error
+	ok := errors.As(target, &err)
+	return ok
+}
+
+// ListResponseMetadata groups fields common for all API List calls,
+// and maps to the Metadata API JSON object.
+type ListResponseMetadata struct {
+	Timestamp  time.Time `json:"RunAt"`
+	Offset     int32     `json:"offset"`
+	Limit      int32     `json:"limit"`
+	ItemsCount int32     `json:"items_count"`
+}
+
+// Folder represents a single folder, and maps to the AggregatePrivateViewFolder
+// JSON API object.
+type Folder struct {
+	Discriminator        string    `json:"discriminator"`
+	Name                 string    `json:"name"`
+	SanitizedName        string    `json:"name_sanitized"`
+	Slug                 string    `json:"slug"`
+	Status               string    `json:"status"`
+	PublicURL            string    `json:"public_url"`
+	IsPasswordProtected  bool      `json:"is_password_protected"`
+	Type                 string    `json:"type"`
+	FileManagerLink      string    `json:"file_manager_link"`
+	ParentFolderSlug     string    `json:"parent_folder_slug"`
+	Privacy              string    `json:"privacy"`
+	Created              time.Time `json:"created"`
+	LastUserModified     time.Time `json:"last_user_modified"`
+	HasSubfolder         bool      `json:"has_subfolder"`
+	HasTrashedSubfolders bool      `json:"has_trashed_subfolders"`
+}
+
+// File represents a single file, and maps to the AggregatePrivateViewFileV3
+// JSON API object.
+type File struct {
+	Discriminator            string `json:"discriminator"`
+	Slug                     string `json:"slug"`
+	URL                      string `json:"url"`
+	Realm                    string `json:"realm"`
+	Name                     string `json:"name"`
+	NameSanitized            string `json:"name_sanitized"`
+	Extension                string `json:"extension"`
+	Filesize                 int64  `json:"filesize"`
+	PasswordProtectedFile    bool   `json:"password_protected_file"`
+	Description              string `json:"description"`
+	DescriptionSanitized     string `json:"description_sanitized"`
+	IsPorn                   bool   `json:"is_porn"`
+	Rating                   int    `json:"rating"`
+	PasswordProtectedArchive bool   `json:"password_protected_archive"`
+	MalwareStatus            string `json:"malware_status"`
+	ContentStatus            string `json:"content_status"`
+	ContentType              string `json:"content_type"`
+	Format                   struct {
+	} `json:"format"`
+	DownloadTypes []interface{} `json:"download_types"`
+	ThumbnailInfo []interface{} `json:"thumbnail_info"`
+	PreviewInfo   struct {
+	} `json:"preview_info"`
+	Privacy          string    `json:"privacy"`
+	IsPornByUploader bool      `json:"is_porn_by_uploader"`
+	ExpireDownload   int       `json:"expire_download"`
+	ExpireTime       time.Time `json:"expire_time"`
+	UploadTime       time.Time `json:"upload_time"`
+	LastUserModified time.Time `json:"last_user_modified"`
+	FolderSlug       string    `json:"folder_slug"`
+	IsIncomplete     bool      `json:"is_incomplete"`
+	IsInTrash        bool      `json:"is_in_trash"`
+	Processing       struct {
+		Identify       bool `json:"identify"`
+		Thumbnails     bool `json:"thumbnails"`
+		LivePreview    bool `json:"live_preview"`
+		ArchiveContent bool `json:"archive_content"`
+		Preview        bool `json:"preview"`
+	} `json:"processing"`
+}
+
+// CreateFolderRequest represents the JSON API object
+// that's sent to the create folder API endpoint.
+type CreateFolderRequest struct {
+	Name             string `json:"name"`
+	ParentFolderSlug string `json:"parent_folder_slug"`
+}
+
+// ListFoldersResponse represents the JSON API object
+// that's received from the list folders API endpoint.
+type ListFoldersResponse struct {
+	Metadata   ListResponseMetadata `json:"metadata"`
+	Folder     Folder               `json:"folder"`
+	Subfolders []Folder             `json:"subfolders"`
+}
+
+// ListFilesResponse represents the JSON API object
+// that's received from the list files API endpoint.
+type ListFilesResponse struct {
+	Metadata ListResponseMetadata `json:"metadata"`
+	Items    []File               `json:"items"`
+}
+
+// DeleteFoldersRequest represents the JSON API object
+// that's sent to the delete folders API endpoint.
+type DeleteFoldersRequest struct {
+	Slugs []string `json:"slugs"`
+}
+
+// CreateUploadURLRequest represents the JSON API object that's
+// sent to the API endpoint generating URLs for new file uploads.
+type CreateUploadURLRequest struct {
+	UserLogin           string `json:"user_login"`
+	Realm               string `json:"realm"`
+	ExistingSessionSlug string `json:"private_slug"`
+}
+
+// CreateUploadURLResponse represents the JSON API object that's
+// received from the API endpoint generating URLs for new file uploads.
+type CreateUploadURLResponse struct {
+	UploadURL        string    `json:"upload_url"`
+	PrivateSlug      string    `json:"private_slug"`
+	ValidUntil       time.Time `json:"valid_until"`
+	ValidityInterval int64     `json:"validity_interval"`
+}
+
+// BatchUpdateFilePropertiesRequest represents the JSON API object that's
+// sent to the API endpoint moving the uploaded files from a scratch space
+// to their final destination.
+type BatchUpdateFilePropertiesRequest struct {
+	Name         string            `json:"name"`
+	FolderSlug   string            `json:"folder_slug"`
+	Description  string            `json:"description"`
+	Slugs        []string          `json:"slugs"`
+	UploadTokens map[string]string `json:"upload_tokens"`
+}
+
+// SendFilePayloadResponse represents the JSON API object that's received
+// in response to uploading a file's body to the CDN URL.
+type SendFilePayloadResponse struct {
+	Size        int    `json:"size"`
+	ContentType string `json:"contentType"`
+	Md5         string `json:"md5"`
+	Message     string `json:"message"`
+	ReturnCode  int    `json:"return_code"`
+	Slug        string `json:"slug"`
+}
+
+// CommitUploadBatchRequest represents the JSON API object that's
+// sent to the API endpoint marking the upload batch as final.
+type CommitUploadBatchRequest struct {
+	Status     string `json:"status"`
+	OwnerLogin string `json:"owner_login"`
+}
+
+// CommitUploadBatchResponse represents the JSON API object that's
+// received from the API endpoint marking the upload batch as final.
+type CommitUploadBatchResponse struct {
+	PrivateSlug          string    `json:"private_slug"`
+	PublicSlug           string    `json:"public_slug"`
+	Status               string    `json:"status"`
+	ConfirmedAt          time.Time `json:"confirmed_at"`
+	Discriminator        string    `json:"discriminator"`
+	Privacy              string    `json:"privacy"`
+	Name                 time.Time `json:"name"`
+	PublicURL            string    `json:"public_url"`
+	FilesCountOk         int       `json:"files_count_ok"`
+	FilesCountTrash      int       `json:"files_count_trash"`
+	FilesCountIncomplete int       `json:"files_count_incomplete"`
+}
+
+// UpdateDescriptionRequest represents the JSON API object that's
+// sent to the file modification API endpoint marking the upload batch as final.
+type UpdateDescriptionRequest struct {
+	Description string `json:"description"`
+}
+
+// GetDownloadLinkRequest represents the JSON API object that's
+// sent to the API endpoint that generates CDN download links for file payloads.
+type GetDownloadLinkRequest struct {
+	Slug      string `json:"file_slug"`
+	UserLogin string `json:"user_login"`
+	DeviceID  string `json:"device_id"`
+}
+
+// GetDownloadLinkResponse represents the JSON API object that's
+// received from the API endpoint that generates CDN download links for file payloads.
+type GetDownloadLinkResponse struct {
+	Link                        string    `json:"link"`
+	DownloadURLValidUntil       time.Time `json:"download_url_valid_until"`
+	DownloadURLValidityInterval int       `json:"download_url_validity_interval"`
+	Hash                        string    `json:"hash"`
+}
+
+// AuthenticateRequest represents the JSON API object that's sent to the auth API endpoint.
+type AuthenticateRequest struct {
+	Login    string `json:"login"`
+	Password string `json:"password"`
+}
+
+// AuthenticateResponse represents the JSON API object that's received from the auth API endpoint.
+type AuthenticateResponse struct {
+	TokenID               string `json:"token_id"`
+	TokenValidityInterval int    `json:"token_validity_interval"`
+	Session               struct {
+		Country          string `json:"country"`
+		IsLimitedCountry bool   `json:"is_limited_country"`
+		User             struct {
+			Login               string `json:"login"`
+			UserID              int64  `json:"user_id"`
+			Credit              int64  `json:"credit"`
+			AvatarURL           string `json:"avatar_url"`
+			FavoritesLink       string `json:"favorites_link"`
+			RootFolderSlug      string `json:"root_folder_slug"`
+			FavoritesFolderSlug string `json:"favorites_folder_slug"`
+			HasCloud            bool   `json:"has_cloud"`
+		} `json:"user"`
+	} `json:"session"`
+}

backend/ulozto/ulozto_test.go

@@ -0,0 +1,117 @@
+package ulozto
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/rclone/rclone/backend/ulozto/api"
+	"github.com/rclone/rclone/fs"
+	"github.com/rclone/rclone/fs/hash"
+	"github.com/rclone/rclone/fs/object"
+	"github.com/rclone/rclone/fs/operations"
+	"github.com/rclone/rclone/fstest"
+	"github.com/stretchr/testify/require"
+
+	"github.com/rclone/rclone/fstest/fstests"
+)
+
+// TestIntegration runs integration tests against the remote
+func TestIntegration(t *testing.T) {
+	fstests.Run(t, &fstests.Opt{
+		RemoteName: "TestUlozto:",
+		NilObject:  (*Object)(nil),
+	})
+}
+
+// TestListWithoutMetadata verifies that basic operations can be performed even if the remote file wasn't written by
+// rclone, or the serialized metadata can't be read.
+func TestListWithoutMetadata(t *testing.T) {
+	const (
+		remoteName = "TestUlozto:"
+		payload    = "42foobar42"
+		sha256     = "d41f400003e93eb0891977f525e73ecedfa04272d2036f6137106168ecb196ab"
+		md5        = "8ad32cfeb3dc0f5092261268f335e0a5"
+		filesize   = len(payload)
+	)
+	ctx := context.Background()
+	fstest.Initialise()
+	subRemoteName, subRemoteLeaf, err := fstest.RandomRemoteName(remoteName)
+	require.NoError(t, err)
+	f, err := fs.NewFs(ctx, subRemoteName)
+	if errors.Is(err, fs.ErrorNotFoundInConfigFile) {
+		t.Logf("Didn't find %q in config file - skipping tests", remoteName)
+		return
+	}
+	require.NoError(t, err)
+
+	file := fstest.Item{ModTime: time.UnixMilli(123456789), Path: subRemoteLeaf, Size: int64(filesize), Hashes: map[hash.Type]string{
+		hash.SHA256: sha256,
+		hash.MD5:    md5,
+	}}
+
+	// Create a file with the given content and metadata
+	obj := fstests.PutTestContents(ctx, t, f, &file, payload, false)
+
+	// Verify the file has been uploaded
+	fstest.CheckListing(t, f, []fstest.Item{file})
+
+	// Now delete the description metadata
+	uloztoObj := obj.(*Object)
+	err = uloztoObj.updateFileProperties(ctx, api.UpdateDescriptionRequest{
+		Description: "",
+	})
+
+	require.NoError(t, err)
+
+	// Listing the file should still succeed, although with estimated mtime and no hashes
+	fileWithoutDetails := fstest.Item{Path: subRemoteLeaf, Size: int64(filesize), ModTime: uloztoObj.remoteFsMtime, Hashes: map[hash.Type]string{
+		hash.SHA256: "",
+		hash.MD5:    "",
+	}}
+	fstest.CheckListing(t, f, []fstest.Item{fileWithoutDetails})
+
+	mtime := time.UnixMilli(987654321)
+
+	// When we update the mtime it should be reflected but hashes should stay intact
+	require.NoError(t, obj.SetModTime(ctx, mtime))
+	updatedMtimeFile := fstest.Item{Path: subRemoteLeaf, Size: int64(filesize), ModTime: mtime, Hashes: map[hash.Type]string{
+		hash.SHA256: "",
+		hash.MD5:    "",
+	}}
+	fstest.CheckListing(t, f, []fstest.Item{updatedMtimeFile})
+
+	// Tear down
+	require.NoError(t, operations.Purge(ctx, f, ""))
+}
+
+// TestUploadLargeFile verifies that files over the supported threshold are not uploaded.
+func TestUploadLargeFile(t *testing.T) {
+	const (
+		remoteName = "TestUlozto:"
+		payload    = "foobar"
+		filesize   = maxFileSizeBytes + 1
+	)
+	ctx := context.Background()
+	fstest.Initialise()
+	subRemoteName, subRemoteLeaf, err := fstest.RandomRemoteName(remoteName)
+	require.NoError(t, err)
+	f, err := fs.NewFs(ctx, subRemoteName)
+	if errors.Is(err, fs.ErrorNotFoundInConfigFile) {
+		t.Logf("Didn't find %q in config file - skipping tests", remoteName)
+		return
+	}
+	require.NoError(t, err)
+
+	file := fstest.Item{ModTime: time.UnixMilli(123456789), Path: subRemoteLeaf, Size: int64(filesize)}
+	obji := object.NewStaticObjectInfo(file.Path, file.ModTime, file.Size, true, nil, nil)
+	// The payload buffer is just a placeholder which shouldn't be used
+	_, err = f.Put(ctx, bytes.NewBufferString(payload), obji)
+
+	require.Error(t, err, "File size over the supported max threshold.")
+
+	// Verify the remote stayed intact
+	fstest.CheckListing(t, f, []fstest.Item{})
+}

bin/make_manual.py

@@ -79,6 +79,7 @@ docs = [
     "storj.md",
     "sugarsync.md",
     "tardigrade.md",            # stub only to redirect to storj.md
+    "ulozto.md",
     "uptobox.md",
     "union.md",
     "webdav.md",

docs/content/_index.md

@@ -180,6 +180,7 @@ WebDAV or S3, that work out of the box.)
 {{< provider name="Synology" home="https://c2.synology.com/en-global/object-storage/overview" config="/s3/#synology-c2" >}}
 {{< provider name="SugarSync" home="https://sugarsync.com/" config="/sugarsync/" >}}
 {{< provider name="Tencent Cloud Object Storage (COS)" home="https://intl.cloud.tencent.com/product/cos" config="/s3/#tencent-cos" >}}
+{{< provider name="Uloz.to" home="https://uloz.to" config="/ulozto/" >}}
 {{< provider name="Uptobox" home="https://uptobox.com" config="/uptobox/" >}}
 {{< provider name="Wasabi" home="https://wasabi.com/" config="/s3/#wasabi" >}}
 {{< provider name="WebDAV" home="https://en.wikipedia.org/wiki/WebDAV" config="/webdav/" >}}

docs/content/docs.md

@@ -77,6 +77,7 @@ See the following for detailed instructions for
   * [Storj](/storj/)
   * [SugarSync](/sugarsync/)
   * [Union](/union/)
+  * [Uloz.to](/ulozto/)
   * [Uptobox](/uptobox/)
   * [WebDAV](/webdav/)
   * [Yandex Disk](/yandex/)

docs/content/overview.md

@@ -57,6 +57,7 @@ Here is an overview of the major features of each cloud storage system.
 | SMB                          | -                 | R/W     | Yes              | No              | -         | -        |
 | SugarSync                    | -                 | -       | No               | No              | -         | -        |
 | Storj                        | -                 | R       | No               | No              | -         | -        |
+| Uloz.to                      | MD5, SHA256 ¹³    | -       | No               | Yes             | -         | -        |
 | Uptobox                      | -                 | -       | No               | Yes             | -         | -        |
 | WebDAV                       | MD5, SHA1 ³       | R ⁴     | Depends          | No              | -         | -        |
 | Yandex Disk                  | MD5               | R/W     | No               | No              | R         | -        |
@@ -100,6 +101,9 @@ hash](https://static.hidrive.com/dev/0001).
 It combines SHA1 sums for each 4 KiB block hierarchically to a single
 top-level sum.
 
+¹³ Uloz.to provides server-calculated MD5 hash upon file upload. MD5 and SHA256
+hashes are client-calculated and stored as metadata fields.
+
 ### Hash ###
 
 The cloud storage system supports various hash types of the objects.
@@ -523,6 +527,7 @@ upon backend-specific capabilities.
 | SMB                          | No    | No   | Yes  | Yes     | No      | No    | Yes          | Yes               | No           | No    | Yes      |
 | SugarSync                    | Yes   | Yes  | Yes  | Yes     | No      | No    | Yes          | No                | Yes          | No    | Yes      |
 | Storj                        | Yes ² | Yes  | Yes  | No      | No      | Yes   | Yes          | No                | Yes          | No    | No       |
+| Uloz.to                      | No    | No   | No   | No      | No      | No    | No           | No                | No           | No    | Yes      |
 | Uptobox                      | No    | Yes  | Yes  | Yes     | No      | No    | No           | No                | No           | No    | No       |
 | WebDAV                       | Yes   | Yes  | Yes  | Yes     | No      | No    | Yes ³        | No                | No           | Yes   | Yes      |
 | Yandex Disk                  | Yes   | Yes  | Yes  | Yes     | Yes     | No    | Yes          | No                | Yes          | Yes   | Yes      |

docs/content/ulozto.md

@@ -0,0 +1,247 @@
+---
+title: "Uloz.to"
+description: "Rclone docs for Uloz.to"
+versionIntroduced: "v1.66"
+---
+
+# {{< icon "fa fa-box-archive" >}} Uloz.to
+
+Paths are specified as `remote:path`
+
+Paths may be as deep as required, e.g. `remote:directory/subdirectory`.
+
+The initial setup for Box involves filling in the user credentials. 
+`rclone config` walks you through it.
+
+## Configuration
+
+Here is an example of how to make a remote called `remote`.  First run:
+
+     rclone config
+
+This will guide you through an interactive setup process:
+
+```
+No remotes found, make a new one?
+n) New remote
+s) Set configuration password
+q) Quit config
+n/s/q> n
+name> remote
+Type of storage to configure.
+Choose a number from below, or type in your own value
+[snip]
+XX / Uloz.to
+   \ "ulozto"
+[snip]
+Storage> ulozto
+
+Option app_token.
+The application token identifying the app. An app API key can be either found in the API doc 
+https://uloz.to/upload-resumable-api-beta or obtained from customer service.
+Enter a value. Press Enter to leave empty.
+app_token> token_value
+
+Option username.
+The username of the principal to operate as.
+Enter a value. Press Enter to leave empty.
+username> user
+
+Option password.
+The password for the user.
+Enter a value. Press Enter to leave empty.
+password> secretPassword
+
+Edit advanced config?
+y) Yes
+n) No (default)
+y/n> n
+
+Keep this "remote" remote?
+y) Yes this is OK (default)
+e) Edit this remote
+d) Delete this remote
+y/e/d> y
+```
+
+Once configured you can then use `rclone` like this,
+
+List folders in root level folder:
+
+    rclone lsd remote:
+
+List all the files in your root folder:
+
+    rclone ls remote:
+
+To copy a local folder to a Uloz.to folder called backup:
+
+    rclone copy /home/source remote:backup
+
+### User credentials
+The only reliable method is to authenticate the user using 
+username and password. Uloz.to offers anb API key as well, but 
+it's reserved for the use of Uloz.to's in-house application
+and using it in different circumstances is unreliable. 
+
+### Modification times and hashes
+
+Uloz.to doesn't allow the user to set a custom modification time,
+or retrieve the hashes after upload. As a result, the integration
+uses a free form field the API provides to encode client-provided
+timestamps and hashes. Timestamps are stored with microsecond 
+precision. 
+
+A server calculated MD5 hash of the file is verified upon upload. 
+Afterwards, the backend only serves the client-side calculated
+hashes. 
+
+### Restricted filename characters
+
+In addition to the [default restricted characters set](/overview/#restricted-characters)
+the following characters are also replaced:
+
+| Character | Value | Replacement |
+| --------- |:-----:|:-----------:|
+| \         | 0x5C  | ＼           |
+
+Invalid UTF-8 bytes will also be [replaced](/overview/#invalid-utf8),
+as they can't be used in JSON strings.
+
+### Transfers
+
+All files are currently uploaded using a single HTTP request, so 
+for uploading large files a stable connection is necesary.  Rclone will
+upload up to `--transfers` chunks at the same time (shared among all 
+uploads).  
+
+### Deleting files
+
+By default, files are moved to the recycle bin whereas folders
+are deleted immediately. Trashed files are permanently deleted after
+30 days in the recycle bin. 
+
+Emptying the trash is currently not implemented in rclone.
+
+### Root folder ID
+
+You can set the `root_folder_slug` for rclone.  This is the folder
+(identified by its `Folder slug`) that rclone considers to be the root
+of your Uloz.to drive.
+
+Normally you will leave this blank and rclone will determine the
+correct root to use itself. However you can set this to restrict rclone
+to a specific folder hierarchy.
+
+In order to do this you will have to find the `Folder slug` of the
+folder you wish to use as root.  This will be the last segment
+of the URL when you open the relevant folder in the Box web
+interface.
+
+For example, for exploring a folder with URL 
+`https://uloz.to/fm/my-files/foobar`, `foobar` should be used as the 
+root slug.
+
+`root_folder_slug` can be used alongside a specific path in the remote 
+path. For example, if your remote's `root_folder_slug` corresponds to `/foo/bar`, 
+`remote:baz/qux` will refer to `ABSOLUTE_ULOZTO_ROOT/foo/bar/baz/qux`.
+
+{{< rem autogenerated options start" - DO NOT EDIT - instead edit fs.RegInfo in backend/ulozto/ulozto.go then run make backenddocs" >}}
+### Standard options
+
+Here are the Standard options specific to ulozto (Uloz.to).
+
+#### --ulozto-app-token
+
+The application token identifying the app. An app API key can be either found in the API doc https://uloz.to/upload-resumable-api-beta or obtained from customer service.
+
+Properties:
+
+- Config:      app_token
+- Env Var:     RCLONE_ULOZTO_APP_TOKEN
+- Type:        string
+- Required:    false
+
+#### --ulozto-username
+
+The username of the principal to operate as.
+
+Properties:
+
+- Config:      username
+- Env Var:     RCLONE_ULOZTO_USERNAME
+- Type:        string
+- Required:    false
+
+#### --ulozto-password
+
+The password for the user.
+
+Properties:
+
+- Config:      password
+- Env Var:     RCLONE_ULOZTO_PASSWORD
+- Type:        string
+- Required:    false
+
+### Advanced options
+
+Here are the Advanced options specific to ulozto (Uloz.to).
+
+#### --ulozto-root-folder-slug
+
+If set, rclone will use this folder as the root folder for all operations. For example, if the slug identifies 'foo/bar/', 'ulozto:baz' is equivalent to 'ulozto:foo/bar/baz' without any root slug set.
+
+Properties:
+
+- Config:      root_folder_slug
+- Env Var:     RCLONE_ULOZTO_ROOT_FOLDER_SLUG
+- Type:        string
+- Required:    false
+
+#### --ulozto-list-page-size
+
+The size of a single page for list commands. 1-500
+
+Properties:
+
+- Config:      list_page_size
+- Env Var:     RCLONE_ULOZTO_LIST_PAGE_SIZE
+- Type:        int
+- Default:     500
+
+#### --ulozto-encoding
+
+The encoding for the backend.
+
+See the [encoding section in the overview](/overview/#encoding) for more info.
+
+Properties:
+
+- Config:      encoding
+- Env Var:     RCLONE_ULOZTO_ENCODING
+- Type:        Encoding
+- Default:     Slash,BackSlash,Del,Ctl,InvalidUtf8,Dot
+
+{{< rem autogenerated options stop >}}
+
+## Limitations
+
+Uloz.to file names can't have the `\` character in.  rclone maps this to
+and from an identical looking unicode equivalent `＼` (U+FF3C Fullwidth
+Reverse Solidus).
+
+Uloz.to only supports filenames up to 255 characters in length.
+
+Uloz.to rate limits access to the API, but exact details are undisclosed. 
+Practical testing reveals that hitting the rate limit during normal use
+is very rare, although not impossible with higher number of concurrently 
+uploaded files.
+
+`rclone about` is not supported by the Uloz.to backend. Although 
+there's an endpoint to retrieve the information for the UI, it's not 
+exposed in the API.  Backends without this capability cannot determine 
+free space for an rclone mount or use policy `mfs` (most free space) 
+as a member of an rclone union remote.
+
+See [List of backends that do not support rclone about](https://rclone.org/overview/#optional-features) and [rclone about](https://rclone.org/commands/rclone_about/)

docs/layouts/chrome/navbar.html

@@ -100,6 +100,7 @@
           <a class="dropdown-item" href="/smb/"><i class="fa fa-server fa-fw"></i> SMB / CIFS</a>
           <a class="dropdown-item" href="/storj/"><i class="fas fa-dove fa-fw"></i> Storj</a>
           <a class="dropdown-item" href="/sugarsync/"><i class="fas fa-dove fa-fw"></i> SugarSync</a>
+          <a class="dropdown-item" href="/uloz.to/"><i class="fa fa-box-archive fa-fw"></i> Uloz.to</a>
           <a class="dropdown-item" href="/uptobox/"><i class="fa fa-archive fa-fw"></i> Uptobox</a>
           <a class="dropdown-item" href="/union/"><i class="fa fa-link fa-fw"></i> Union (merge backends)</a>
           <a class="dropdown-item" href="/webdav/"><i class="fa fa-server fa-fw"></i> WebDAV</a>

fstest/test_all/config.yaml

@@ -458,3 +458,6 @@ backends:
  - backend:  "quatrix"
    remote:   "TestQuatrix:"
    fastlist: false
+ - backend:  "ulozto"
+   remote:   "TestUlozto:"
+   fastlist: false