fix(driver): Handle Lanzou anti-crawler challenge by recalculating cookies (#9364)

- Detect and solve `acw_sc__v2` challenge to bypass anti-crawler validation
- Refactored request header initialization logic for clarity

drivers/189/driver.go

@@ -80,9 +80,10 @@ func (d *Cloud189) Link(ctx context.Context, file model.Obj, args model.LinkArgs
 }
 
 func (d *Cloud189) MakeDir(ctx context.Context, parentDir model.Obj, dirName string) error {
+	safeName := d.sanitizeName(dirName)
 	form := map[string]string{
 		"parentFolderId": parentDir.GetID(),
-		"folderName":     dirName,
+		"folderName":     safeName,
 	}
 	_, err := d.request("https://cloud.189.cn/api/open/file/createFolder.action", http.MethodPost, func(req *resty.Request) {
 		req.SetFormData(form)
@@ -126,9 +127,10 @@ func (d *Cloud189) Rename(ctx context.Context, srcObj model.Obj, newName string)
 		idKey = "folderId"
 		nameKey = "destFolderName"
 	}
+	safeName := d.sanitizeName(newName)
 	form := map[string]string{
 		idKey:   srcObj.GetID(),
-		nameKey: newName,
+		nameKey: safeName,
 	}
 	_, err := d.request(url, http.MethodPost, func(req *resty.Request) {
 		req.SetFormData(form)

drivers/189/meta.go

@@ -6,9 +6,10 @@ import (
 )
 
 type Addition struct {
-	Username string `json:"username" required:"true"`
-	Password string `json:"password" required:"true"`
-	Cookie   string `json:"cookie" help:"Fill in the cookie if need captcha"`
+	Username   string `json:"username" required:"true"`
+	Password   string `json:"password" required:"true"`
+	Cookie     string `json:"cookie" help:"Fill in the cookie if need captcha"`
+	StripEmoji bool   `json:"strip_emoji" help:"Remove four-byte characters (e.g., emoji) before upload"`
 	driver.RootID
 }
 

drivers/189/util.go

@@ -11,9 +11,11 @@ import (
 	"io"
 	"math"
 	"net/http"
+	"path"
 	"strconv"
 	"strings"
 	"time"
+	"unicode/utf8"
 
 	"github.com/alist-org/alist/v3/drivers/base"
 	"github.com/alist-org/alist/v3/internal/driver"
@@ -222,13 +224,37 @@ func (d *Cloud189) getFiles(fileId string) ([]model.Obj, error) {
 	return res, nil
 }
 
+func (d *Cloud189) sanitizeName(name string) string {
+	if !d.StripEmoji {
+		return name
+	}
+	b := strings.Builder{}
+	for _, r := range name {
+		if utf8.RuneLen(r) == 4 {
+			continue
+		}
+		b.WriteRune(r)
+	}
+	sanitized := b.String()
+	if sanitized == "" {
+		ext := path.Ext(name)
+		if ext != "" {
+			sanitized = "file" + ext
+		} else {
+			sanitized = "file"
+		}
+	}
+	return sanitized
+}
+
 func (d *Cloud189) oldUpload(dstDir model.Obj, file model.FileStreamer) error {
+	safeName := d.sanitizeName(file.GetName())
 	res, err := d.client.R().SetMultipartFormData(map[string]string{
 		"parentId":   dstDir.GetID(),
 		"sessionKey": "??",
 		"opertype":   "1",
-		"fname":      file.GetName(),
-	}).SetMultipartField("Filedata", file.GetName(), file.GetMimetype(), file).Post("https://hb02.upload.cloud.189.cn/v1/DCIWebUploadAction")
+		"fname":      safeName,
+	}).SetMultipartField("Filedata", safeName, file.GetMimetype(), file).Post("https://hb02.upload.cloud.189.cn/v1/DCIWebUploadAction")
 	if err != nil {
 		return err
 	}
@@ -313,9 +339,10 @@ func (d *Cloud189) newUpload(ctx context.Context, dstDir model.Obj, file model.F
 	const DEFAULT int64 = 10485760
 	var count = int64(math.Ceil(float64(file.GetSize()) / float64(DEFAULT)))
 
+	safeName := d.sanitizeName(file.GetName())
 	res, err := d.uploadRequest("/person/initMultiUpload", map[string]string{
 		"parentFolderId": dstDir.GetID(),
-		"fileName":       encode(file.GetName()),
+		"fileName":       encode(safeName),
 		"fileSize":       strconv.FormatInt(file.GetSize(), 10),
 		"sliceSize":      strconv.FormatInt(DEFAULT, 10),
 		"lazyCheck":      "1",

drivers/189pc/driver.go

@@ -205,10 +205,11 @@ func (y *Cloud189PC) MakeDir(ctx context.Context, parentDir model.Obj, dirName s
 	fullUrl += "/createFolder.action"
 
 	var newFolder Cloud189Folder
+	safeName := y.sanitizeName(dirName)
 	_, err := y.post(fullUrl, func(req *resty.Request) {
 		req.SetContext(ctx)
 		req.SetQueryParams(map[string]string{
-			"folderName":   dirName,
+			"folderName":   safeName,
 			"relativePath": "",
 		})
 		if isFamily {
@@ -225,6 +226,7 @@ func (y *Cloud189PC) MakeDir(ctx context.Context, parentDir model.Obj, dirName s
 	if err != nil {
 		return nil, err
 	}
+	newFolder.Name = safeName
 	return &newFolder, nil
 }
 
@@ -258,21 +260,29 @@ func (y *Cloud189PC) Rename(ctx context.Context, srcObj model.Obj, newName strin
 	}
 
 	var newObj model.Obj
+	safeName := y.sanitizeName(newName)
 	switch f := srcObj.(type) {
 	case *Cloud189File:
 		fullUrl += "/renameFile.action"
 		queryParam["fileId"] = srcObj.GetID()
-		queryParam["destFileName"] = newName
+		queryParam["destFileName"] = safeName
 		newObj = &Cloud189File{Icon: f.Icon} // 复用预览
 	case *Cloud189Folder:
 		fullUrl += "/renameFolder.action"
 		queryParam["folderId"] = srcObj.GetID()
-		queryParam["destFolderName"] = newName
+		queryParam["destFolderName"] = safeName
 		newObj = &Cloud189Folder{}
 	default:
 		return nil, errs.NotSupport
 	}
 
+	switch obj := newObj.(type) {
+	case *Cloud189File:
+		obj.Name = safeName
+	case *Cloud189Folder:
+		obj.Name = safeName
+	}
+
 	_, err := y.request(fullUrl, method, func(req *resty.Request) {
 		req.SetContext(ctx).SetQueryParams(queryParam)
 	}, nil, newObj, isFamily)

drivers/189pc/meta.go

@@ -6,9 +6,10 @@ import (
 )
 
 type Addition struct {
-	Username string `json:"username" required:"true"`
-	Password string `json:"password" required:"true"`
-	VCode    string `json:"validate_code"`
+	Username   string `json:"username" required:"true"`
+	Password   string `json:"password" required:"true"`
+	VCode      string `json:"validate_code"`
+	StripEmoji bool   `json:"strip_emoji" help:"Remove four-byte characters (e.g., emoji) before upload"`
 	driver.RootID
 	OrderBy        string `json:"order_by" type:"select" options:"filename,filesize,lastOpTime" default:"filename"`
 	OrderDirection string `json:"order_direction" type:"select" options:"asc,desc" default:"asc"`

drivers/189pc/utils.go

@@ -12,11 +12,13 @@ import (
 	"net/http/cookiejar"
 	"net/url"
 	"os"
+	"path"
 	"regexp"
 	"sort"
 	"strconv"
 	"strings"
 	"time"
+	"unicode/utf8"
 
 	"golang.org/x/sync/semaphore"
 
@@ -57,6 +59,29 @@ const (
 	CHANNEL_ID = "web_cloud.189.cn"
 )
 
+func (y *Cloud189PC) sanitizeName(name string) string {
+	if !y.StripEmoji {
+		return name
+	}
+	b := strings.Builder{}
+	for _, r := range name {
+		if utf8.RuneLen(r) == 4 {
+			continue
+		}
+		b.WriteRune(r)
+	}
+	sanitized := b.String()
+	if sanitized == "" {
+		ext := path.Ext(name)
+		if ext != "" {
+			sanitized = "file" + ext
+		} else {
+			sanitized = "file"
+		}
+	}
+	return sanitized
+}
+
 func (y *Cloud189PC) SignatureHeader(url, method, params string, isFamily bool) map[string]string {
 	dateOfGmt := getHttpDateStr()
 	sessionKey := y.getTokenInfo().SessionKey
@@ -475,10 +500,11 @@ func (y *Cloud189PC) refreshSession() (err error) {
 func (y *Cloud189PC) StreamUpload(ctx context.Context, dstDir model.Obj, file model.FileStreamer, up driver.UpdateProgress, isFamily bool, overwrite bool) (model.Obj, error) {
 	size := file.GetSize()
 	sliceSize := partSize(size)
+	safeName := y.sanitizeName(file.GetName())
 
 	params := Params{
 		"parentFolderId": dstDir.GetID(),
-		"fileName":       url.QueryEscape(file.GetName()),
+		"fileName":       url.QueryEscape(safeName),
 		"fileSize":       fmt.Sprint(file.GetSize()),
 		"sliceSize":      fmt.Sprint(sliceSize),
 		"lazyCheck":      "1",
@@ -596,7 +622,8 @@ func (y *Cloud189PC) RapidUpload(ctx context.Context, dstDir model.Obj, stream m
 		return nil, errors.New("invalid hash")
 	}
 
-	uploadInfo, err := y.OldUploadCreate(ctx, dstDir.GetID(), fileMd5, stream.GetName(), fmt.Sprint(stream.GetSize()), isFamily)
+	safeName := y.sanitizeName(stream.GetName())
+	uploadInfo, err := y.OldUploadCreate(ctx, dstDir.GetID(), fileMd5, safeName, fmt.Sprint(stream.GetSize()), isFamily)
 	if err != nil {
 		return nil, err
 	}
@@ -615,6 +642,7 @@ func (y *Cloud189PC) FastUpload(ctx context.Context, dstDir model.Obj, file mode
 		tmpF  *os.File
 		err   error
 	)
+	safeName := y.sanitizeName(file.GetName())
 	size := file.GetSize()
 	if _, ok := cache.(io.ReaderAt); !ok && size > 0 {
 		tmpF, err = os.CreateTemp(conf.Conf.TempDir, "file-*")
@@ -697,7 +725,7 @@ func (y *Cloud189PC) FastUpload(ctx context.Context, dstDir model.Obj, file mode
 		//step.2 预上传
 		params := Params{
 			"parentFolderId": dstDir.GetID(),
-			"fileName":       url.QueryEscape(file.GetName()),
+			"fileName":       url.QueryEscape(safeName),
 			"fileSize":       fmt.Sprint(file.GetSize()),
 			"fileMd5":        fileMd5Hex,
 			"sliceSize":      fmt.Sprint(sliceSize),
@@ -833,9 +861,10 @@ func (y *Cloud189PC) OldUpload(ctx context.Context, dstDir model.Obj, file model
 		return nil, err
 	}
 	rateLimited := driver.NewLimitedUploadStream(ctx, io.NopCloser(tempFile))
+	safeName := y.sanitizeName(file.GetName())
 
 	// 创建上传会话
-	uploadInfo, err := y.OldUploadCreate(ctx, dstDir.GetID(), fileMd5, file.GetName(), fmt.Sprint(file.GetSize()), isFamily)
+	uploadInfo, err := y.OldUploadCreate(ctx, dstDir.GetID(), fileMd5, safeName, fmt.Sprint(file.GetSize()), isFamily)
 	if err != nil {
 		return nil, err
 	}

drivers/all.go

@@ -31,6 +31,7 @@ import (
 	_ "github.com/alist-org/alist/v3/drivers/dropbox"
 	_ "github.com/alist-org/alist/v3/drivers/febbox"
 	_ "github.com/alist-org/alist/v3/drivers/ftp"
+	_ "github.com/alist-org/alist/v3/drivers/gitee"
 	_ "github.com/alist-org/alist/v3/drivers/github"
 	_ "github.com/alist-org/alist/v3/drivers/github_releases"
 	_ "github.com/alist-org/alist/v3/drivers/gofile"

drivers/gitee/driver.go

@@ -0,0 +1,224 @@
+package gitee
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	stdpath "path"
+	"strings"
+
+	"github.com/alist-org/alist/v3/drivers/base"
+	"github.com/alist-org/alist/v3/internal/driver"
+	"github.com/alist-org/alist/v3/internal/errs"
+	"github.com/alist-org/alist/v3/internal/model"
+	"github.com/alist-org/alist/v3/pkg/utils"
+	"github.com/go-resty/resty/v2"
+)
+
+type Gitee struct {
+	model.Storage
+	Addition
+	client *resty.Client
+}
+
+func (d *Gitee) Config() driver.Config {
+	return config
+}
+
+func (d *Gitee) GetAddition() driver.Additional {
+	return &d.Addition
+}
+
+func (d *Gitee) Init(ctx context.Context) error {
+	d.RootFolderPath = utils.FixAndCleanPath(d.RootFolderPath)
+	d.Endpoint = strings.TrimSpace(d.Endpoint)
+	if d.Endpoint == "" {
+		d.Endpoint = "https://gitee.com/api/v5"
+	}
+	d.Endpoint = strings.TrimSuffix(d.Endpoint, "/")
+	d.Owner = strings.TrimSpace(d.Owner)
+	d.Repo = strings.TrimSpace(d.Repo)
+	d.Token = strings.TrimSpace(d.Token)
+	d.DownloadProxy = strings.TrimSpace(d.DownloadProxy)
+	if d.Owner == "" || d.Repo == "" {
+		return errors.New("owner and repo are required")
+	}
+	d.client = base.NewRestyClient().
+		SetBaseURL(d.Endpoint).
+		SetHeader("Accept", "application/json")
+	repo, err := d.getRepo()
+	if err != nil {
+		return err
+	}
+	d.Ref = strings.TrimSpace(d.Ref)
+	if d.Ref == "" {
+		d.Ref = repo.DefaultBranch
+	}
+	return nil
+}
+
+func (d *Gitee) Drop(ctx context.Context) error {
+	return nil
+}
+
+func (d *Gitee) List(ctx context.Context, dir model.Obj, args model.ListArgs) ([]model.Obj, error) {
+	relPath := d.relativePath(dir.GetPath())
+	contents, err := d.listContents(relPath)
+	if err != nil {
+		return nil, err
+	}
+	objs := make([]model.Obj, 0, len(contents))
+	for i := range contents {
+		objs = append(objs, contents[i].toModelObj())
+	}
+	return objs, nil
+}
+
+func (d *Gitee) Link(ctx context.Context, file model.Obj, args model.LinkArgs) (*model.Link, error) {
+	var downloadURL string
+	if obj, ok := file.(*Object); ok {
+		downloadURL = obj.DownloadURL
+		if downloadURL == "" {
+			relPath := d.relativePath(file.GetPath())
+			content, err := d.getContent(relPath)
+			if err != nil {
+				return nil, err
+			}
+			if content.DownloadURL == "" {
+				return nil, errors.New("empty download url")
+			}
+			obj.DownloadURL = content.DownloadURL
+			downloadURL = content.DownloadURL
+		}
+	} else {
+		relPath := d.relativePath(file.GetPath())
+		content, err := d.getContent(relPath)
+		if err != nil {
+			return nil, err
+		}
+		if content.DownloadURL == "" {
+			return nil, errors.New("empty download url")
+		}
+		downloadURL = content.DownloadURL
+	}
+	url := d.applyProxy(downloadURL)
+	return &model.Link{
+		URL: url,
+		Header: http.Header{
+			"Cookie": {d.Cookie},
+		},
+	}, nil
+}
+
+func (d *Gitee) newRequest() *resty.Request {
+	req := d.client.R()
+	if d.Token != "" {
+		req.SetQueryParam("access_token", d.Token)
+	}
+	if d.Ref != "" {
+		req.SetQueryParam("ref", d.Ref)
+	}
+	return req
+}
+
+func (d *Gitee) apiPath(path string) string {
+	escapedOwner := url.PathEscape(d.Owner)
+	escapedRepo := url.PathEscape(d.Repo)
+	if path == "" {
+		return fmt.Sprintf("/repos/%s/%s/contents", escapedOwner, escapedRepo)
+	}
+	return fmt.Sprintf("/repos/%s/%s/contents/%s", escapedOwner, escapedRepo, encodePath(path))
+}
+
+func (d *Gitee) listContents(path string) ([]Content, error) {
+	res, err := d.newRequest().Get(d.apiPath(path))
+	if err != nil {
+		return nil, err
+	}
+	if res.IsError() {
+		return nil, toErr(res)
+	}
+	var contents []Content
+	if err := utils.Json.Unmarshal(res.Body(), &contents); err != nil {
+		var single Content
+		if err2 := utils.Json.Unmarshal(res.Body(), &single); err2 == nil && single.Type != "" {
+			if single.Type != "dir" {
+				return nil, errs.NotFolder
+			}
+			return []Content{}, nil
+		}
+		return nil, err
+	}
+	for i := range contents {
+		contents[i].Path = joinPath(path, contents[i].Name)
+	}
+	return contents, nil
+}
+
+func (d *Gitee) getContent(path string) (*Content, error) {
+	res, err := d.newRequest().Get(d.apiPath(path))
+	if err != nil {
+		return nil, err
+	}
+	if res.IsError() {
+		return nil, toErr(res)
+	}
+	var content Content
+	if err := utils.Json.Unmarshal(res.Body(), &content); err != nil {
+		return nil, err
+	}
+	if content.Type == "" {
+		return nil, errors.New("invalid response")
+	}
+	if content.Path == "" {
+		content.Path = path
+	}
+	return &content, nil
+}
+
+func (d *Gitee) relativePath(full string) string {
+	full = utils.FixAndCleanPath(full)
+	root := utils.FixAndCleanPath(d.RootFolderPath)
+	if root == "/" {
+		return strings.TrimPrefix(full, "/")
+	}
+	if utils.PathEqual(full, root) {
+		return ""
+	}
+	prefix := utils.PathAddSeparatorSuffix(root)
+	if strings.HasPrefix(full, prefix) {
+		return strings.TrimPrefix(full, prefix)
+	}
+	return strings.TrimPrefix(full, "/")
+}
+
+func (d *Gitee) applyProxy(raw string) string {
+	if raw == "" || d.DownloadProxy == "" {
+		return raw
+	}
+	proxy := d.DownloadProxy
+	if !strings.HasSuffix(proxy, "/") {
+		proxy += "/"
+	}
+	return proxy + strings.TrimLeft(raw, "/")
+}
+
+func encodePath(p string) string {
+	if p == "" {
+		return ""
+	}
+	parts := strings.Split(p, "/")
+	for i, part := range parts {
+		parts[i] = url.PathEscape(part)
+	}
+	return strings.Join(parts, "/")
+}
+
+func joinPath(base, name string) string {
+	if base == "" {
+		return name
+	}
+	return strings.TrimPrefix(stdpath.Join(base, name), "./")
+}

drivers/gitee/meta.go

@@ -0,0 +1,29 @@
+package gitee
+
+import (
+	"github.com/alist-org/alist/v3/internal/driver"
+	"github.com/alist-org/alist/v3/internal/op"
+)
+
+type Addition struct {
+	driver.RootPath
+	Endpoint      string `json:"endpoint" type:"string" help:"Gitee API endpoint, default https://gitee.com/api/v5"`
+	Token         string `json:"token" type:"string"`
+	Owner         string `json:"owner" type:"string" required:"true"`
+	Repo          string `json:"repo" type:"string" required:"true"`
+	Ref           string `json:"ref" type:"string" help:"Branch, tag or commit SHA, defaults to repository default branch"`
+	DownloadProxy string `json:"download_proxy" type:"string" help:"Prefix added before download URLs, e.g. https://mirror.example.com/"`
+	Cookie        string `json:"cookie" type:"string" help:"Cookie returned from user info request"`
+}
+
+var config = driver.Config{
+	Name:        "Gitee",
+	LocalSort:   true,
+	DefaultRoot: "/",
+}
+
+func init() {
+	op.RegisterDriver(func() driver.Driver {
+		return &Gitee{}
+	})
+}

drivers/gitee/types.go

@@ -0,0 +1,60 @@
+package gitee
+
+import (
+	"time"
+
+	"github.com/alist-org/alist/v3/internal/model"
+)
+
+type Links struct {
+	Self string `json:"self"`
+	Html string `json:"html"`
+}
+
+type Content struct {
+	Type        string `json:"type"`
+	Size        *int64 `json:"size"`
+	Name        string `json:"name"`
+	Path        string `json:"path"`
+	Sha         string `json:"sha"`
+	URL         string `json:"url"`
+	HtmlURL     string `json:"html_url"`
+	DownloadURL string `json:"download_url"`
+	Links       Links  `json:"_links"`
+}
+
+func (c Content) toModelObj() model.Obj {
+	size := int64(0)
+	if c.Size != nil {
+		size = *c.Size
+	}
+	return &Object{
+		Object: model.Object{
+			ID:       c.Path,
+			Name:     c.Name,
+			Size:     size,
+			Modified: time.Unix(0, 0),
+			IsFolder: c.Type == "dir",
+		},
+		DownloadURL: c.DownloadURL,
+		HtmlURL:     c.HtmlURL,
+	}
+}
+
+type Object struct {
+	model.Object
+	DownloadURL string
+	HtmlURL     string
+}
+
+func (o *Object) URL() string {
+	return o.DownloadURL
+}
+
+type Repo struct {
+	DefaultBranch string `json:"default_branch"`
+}
+
+type ErrResp struct {
+	Message string `json:"message"`
+}

drivers/gitee/util.go

@@ -0,0 +1,44 @@
+package gitee
+
+import (
+	"fmt"
+	"net/url"
+
+	"github.com/alist-org/alist/v3/pkg/utils"
+	"github.com/go-resty/resty/v2"
+)
+
+func (d *Gitee) getRepo() (*Repo, error) {
+	req := d.client.R()
+	if d.Token != "" {
+		req.SetQueryParam("access_token", d.Token)
+	}
+	if d.Cookie != "" {
+		req.SetHeader("Cookie", d.Cookie)
+	}
+	escapedOwner := url.PathEscape(d.Owner)
+	escapedRepo := url.PathEscape(d.Repo)
+	res, err := req.Get(fmt.Sprintf("/repos/%s/%s", escapedOwner, escapedRepo))
+	if err != nil {
+		return nil, err
+	}
+	if res.IsError() {
+		return nil, toErr(res)
+	}
+	var repo Repo
+	if err := utils.Json.Unmarshal(res.Body(), &repo); err != nil {
+		return nil, err
+	}
+	if repo.DefaultBranch == "" {
+		return nil, fmt.Errorf("failed to fetch default branch")
+	}
+	return &repo, nil
+}
+
+func toErr(res *resty.Response) error {
+	var errMsg ErrResp
+	if err := utils.Json.Unmarshal(res.Body(), &errMsg); err == nil && errMsg.Message != "" {
+		return fmt.Errorf("%s: %s", res.Status(), errMsg.Message)
+	}
+	return fmt.Errorf(res.Status())
+}

drivers/lanzou/util.go

@@ -430,17 +430,35 @@ func (d *LanZou) getFilesByShareUrl(shareID, pwd string, sharePageData string) (
 	file.Time = timeFindReg.FindString(sharePageData)
 
 	// 重定向获取真实链接
-	res, err := base.NoRedirectClient.R().SetHeaders(map[string]string{
+	headers := map[string]string{
 		"accept-language": "zh-CN,zh;q=0.9,en;q=0.8,en-GB;q=0.7,en-US;q=0.6",
-	}).Get(downloadUrl)
+	}
+	res, err := base.NoRedirectClient.R().SetHeaders(headers).Get(downloadUrl)
 	if err != nil {
 		return nil, err
 	}
 
+	rPageData := res.String()
+	if findAcwScV2Reg.MatchString(rPageData) {
+		log.Debug("lanzou: detected acw_sc__v2 challenge, recalculating cookie")
+		acwScV2, err := CalcAcwScV2(rPageData)
+		if err != nil {
+			return nil, err
+		}
+		// retry with calculated cookie to bypass anti-crawler validation
+		res, err = base.NoRedirectClient.R().
+			SetHeaders(headers).
+			SetCookie(&http.Cookie{Name: "acw_sc__v2", Value: acwScV2}).
+			Get(downloadUrl)
+		if err != nil {
+			return nil, err
+		}
+		rPageData = res.String()
+	}
+
 	file.Url = res.Header().Get("location")
 
 	// 触发验证
-	rPageData := res.String()
 	if res.StatusCode() != 302 {
 		param, err = htmlJsonToMap(rPageData)
 		if err != nil {