feat(driver): add emby driver (#9574)

Mount an Emby/Jellyfin media server as a storage:
- username/password login with automatic re-login on 401
- library views as root, ID-based hierarchical browsing with pagination
- real filenames/sizes resolved from item Path and MediaSources
- primary image as thumbnail
- direct download link, falling back to static stream when the
  user has no download permission

Close #9573

drivers/all.go

@@ -33,6 +33,7 @@ import (
 	_ "github.com/alist-org/alist/v3/drivers/doubao_new"
 	_ "github.com/alist-org/alist/v3/drivers/doubao_share"
 	_ "github.com/alist-org/alist/v3/drivers/dropbox"
+	_ "github.com/alist-org/alist/v3/drivers/emby"
 	_ "github.com/alist-org/alist/v3/drivers/febbox"
 	_ "github.com/alist-org/alist/v3/drivers/ftp"
 	_ "github.com/alist-org/alist/v3/drivers/ftps"

drivers/emby/driver.go

@@ -0,0 +1,120 @@
+package emby
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+	"sync"
+
+	"github.com/alist-org/alist/v3/internal/driver"
+	"github.com/alist-org/alist/v3/internal/model"
+)
+
+type Emby struct {
+	model.Storage
+	Addition
+
+	token       string
+	userID      string
+	canDownload bool
+	loginMutex  sync.Mutex
+}
+
+func (d *Emby) Config() driver.Config {
+	return config
+}
+
+func (d *Emby) GetAddition() driver.Additional {
+	return &d.Addition
+}
+
+func (d *Emby) Init(ctx context.Context) error {
+	return d.relogin(ctx)
+}
+
+func (d *Emby) Drop(ctx context.Context) error {
+	return nil
+}
+
+func (d *Emby) GetRoot(ctx context.Context) (model.Obj, error) {
+	return &model.Object{
+		ID:       d.RootFolderID,
+		Path:     "/",
+		Name:     "root",
+		IsFolder: true,
+	}, nil
+}
+
+func (d *Emby) List(ctx context.Context, dir model.Obj, args model.ListArgs) ([]model.Obj, error) {
+	if err := d.ensureLogin(ctx); err != nil {
+		return nil, err
+	}
+
+	// root without a root_folder_id: list library views
+	if dir.GetID() == "" {
+		var resp ItemsResp
+		if err := d.request(ctx, "/Users/"+d.userID+"/Views", nil, &resp); err != nil {
+			return nil, err
+		}
+		objs := make([]model.Obj, 0, len(resp.Items))
+		for _, item := range resp.Items {
+			objs = append(objs, d.toObj(item))
+		}
+		return objs, nil
+	}
+
+	const pageSize = 1000
+	var objs []model.Obj
+	for start := 0; ; start += pageSize {
+		var resp ItemsResp
+		err := d.request(ctx, "/Users/"+d.userID+"/Items", map[string]string{
+			"ParentId":   dir.GetID(),
+			"Fields":     "DateCreated,Path,MediaSources",
+			"StartIndex": strconv.Itoa(start),
+			"Limit":      strconv.Itoa(pageSize),
+		}, &resp)
+		if err != nil {
+			return nil, err
+		}
+		for _, item := range resp.Items {
+			objs = append(objs, d.toObj(item))
+		}
+		if start+len(resp.Items) >= resp.TotalRecordCount || len(resp.Items) == 0 {
+			break
+		}
+	}
+	return objs, nil
+}
+
+func (d *Emby) Link(ctx context.Context, file model.Obj, args model.LinkArgs) (*model.Link, error) {
+	if err := d.ensureLogin(ctx); err != nil {
+		return nil, err
+	}
+	if d.canDownload {
+		return &model.Link{
+			URL: fmt.Sprintf("%s/Items/%s/Download?api_key=%s", d.baseURL(), file.GetID(), d.token),
+		}, nil
+	}
+	// no download permission: fall back to the direct-play stream of the original file
+	var resp ItemsResp
+	err := d.request(ctx, "/Users/"+d.userID+"/Items", map[string]string{"Ids": file.GetID()}, &resp)
+	if err != nil {
+		return nil, err
+	}
+	if len(resp.Items) > 0 {
+		switch resp.Items[0].MediaType {
+		case "Video":
+			return &model.Link{
+				URL: fmt.Sprintf("%s/Videos/%s/stream?static=true&api_key=%s", d.baseURL(), file.GetID(), d.token),
+			}, nil
+		case "Audio":
+			return &model.Link{
+				URL: fmt.Sprintf("%s/Audio/%s/stream?static=true&api_key=%s", d.baseURL(), file.GetID(), d.token),
+			}, nil
+		}
+	}
+	return nil, fmt.Errorf("emby user has no download permission and item is not streamable")
+}
+
+var _ driver.Driver = (*Emby)(nil)
+var _ driver.GetRooter = (*Emby)(nil)

drivers/emby/meta.go

@@ -0,0 +1,28 @@
+package emby
+
+import (
+	"github.com/alist-org/alist/v3/internal/driver"
+	"github.com/alist-org/alist/v3/internal/op"
+)
+
+type Addition struct {
+	// Leave root_folder_id empty to list all library views
+	driver.RootID
+	Address  string `json:"address" required:"true" help:"Emby/Jellyfin server address, e.g. http://192.168.1.1:8096"`
+	Username string `json:"username" required:"true"`
+	Password string `json:"password"`
+}
+
+var config = driver.Config{
+	Name:        "Emby",
+	LocalSort:   true,
+	NoUpload:    true,
+	DefaultRoot: "",
+	Alert:       "info|Direct links contain your Emby access token. Enable proxy for this storage if it is shared publicly.",
+}
+
+func init() {
+	op.RegisterDriver(func() driver.Driver {
+		return &Emby{}
+	})
+}

drivers/emby/types.go

@@ -0,0 +1,37 @@
+package emby
+
+import "time"
+
+type AuthResp struct {
+	User struct {
+		Id     string `json:"Id"`
+		Policy struct {
+			EnableContentDownloading bool `json:"EnableContentDownloading"`
+		} `json:"Policy"`
+	} `json:"User"`
+	AccessToken string `json:"AccessToken"`
+}
+
+type MediaSource struct {
+	Path string `json:"Path"`
+	Size int64  `json:"Size"`
+}
+
+type Item struct {
+	Id           string            `json:"Id"`
+	Name         string            `json:"Name"`
+	Type         string            `json:"Type"`
+	MediaType    string            `json:"MediaType"`
+	IsFolder     bool              `json:"IsFolder"`
+	Path         string            `json:"Path"`
+	Container    string            `json:"Container"`
+	Size         int64             `json:"Size"`
+	DateCreated  time.Time         `json:"DateCreated"`
+	MediaSources []MediaSource     `json:"MediaSources"`
+	ImageTags    map[string]string `json:"ImageTags"`
+}
+
+type ItemsResp struct {
+	Items            []Item `json:"Items"`
+	TotalRecordCount int    `json:"TotalRecordCount"`
+}

drivers/emby/util.go

@@ -0,0 +1,127 @@
+package emby
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"path"
+	"strings"
+
+	"github.com/alist-org/alist/v3/drivers/base"
+	"github.com/alist-org/alist/v3/internal/model"
+	"github.com/go-resty/resty/v2"
+)
+
+const authHeader = `MediaBrowser Client="AList", Device="AList", DeviceId="AList", Version="3.0.0"`
+
+func (d *Emby) baseURL() string {
+	return strings.TrimRight(d.Address, "/")
+}
+
+func (d *Emby) login(ctx context.Context) error {
+	var resp AuthResp
+	res, err := base.RestyClient.R().
+		SetContext(ctx).
+		SetHeader("X-Emby-Authorization", authHeader).
+		SetBody(map[string]string{
+			"Username": d.Username,
+			"Pw":       d.Password,
+		}).
+		SetResult(&resp).
+		Post(d.baseURL() + "/Users/AuthenticateByName")
+	if err != nil {
+		return err
+	}
+	if res.StatusCode() != http.StatusOK {
+		return fmt.Errorf("emby login failed: %s: %s", res.Status(), res.String())
+	}
+	if resp.AccessToken == "" || resp.User.Id == "" {
+		return fmt.Errorf("emby login failed: empty token or user id in response")
+	}
+	d.token = resp.AccessToken
+	d.userID = resp.User.Id
+	d.canDownload = resp.User.Policy.EnableContentDownloading
+	return nil
+}
+
+func (d *Emby) ensureLogin(ctx context.Context) error {
+	d.loginMutex.Lock()
+	defer d.loginMutex.Unlock()
+	if d.token != "" {
+		return nil
+	}
+	return d.login(ctx)
+}
+
+func (d *Emby) relogin(ctx context.Context) error {
+	d.loginMutex.Lock()
+	defer d.loginMutex.Unlock()
+	return d.login(ctx)
+}
+
+// request sends an authenticated GET request, re-logging in once on 401
+func (d *Emby) request(ctx context.Context, path string, query map[string]string, out interface{}) error {
+	if err := d.ensureLogin(ctx); err != nil {
+		return err
+	}
+	do := func() (*resty.Response, error) {
+		return base.RestyClient.R().
+			SetContext(ctx).
+			SetHeader("X-Emby-Token", d.token).
+			SetQueryParams(query).
+			SetResult(out).
+			Get(d.baseURL() + path)
+	}
+	res, err := do()
+	if err != nil {
+		return err
+	}
+	if res.StatusCode() == http.StatusUnauthorized {
+		if err = d.relogin(ctx); err != nil {
+			return err
+		}
+		res, err = do()
+		if err != nil {
+			return err
+		}
+	}
+	if res.StatusCode() != http.StatusOK {
+		return fmt.Errorf("emby request failed: %s: %s", res.Status(), res.String())
+	}
+	return nil
+}
+
+// toObj converts an emby item to an alist object
+func (d *Emby) toObj(item Item) model.Obj {
+	name := item.Name
+	size := item.Size
+	if !item.IsFolder {
+		// prefer the real filename so the extension is kept for players
+		if item.Path != "" {
+			name = path.Base(strings.ReplaceAll(item.Path, "\\", "/"))
+		} else if len(item.MediaSources) > 0 && item.MediaSources[0].Path != "" {
+			name = path.Base(strings.ReplaceAll(item.MediaSources[0].Path, "\\", "/"))
+		} else if item.Container != "" && !strings.Contains(item.Container, ",") {
+			name = item.Name + "." + item.Container
+		}
+		if size == 0 && len(item.MediaSources) > 0 {
+			size = item.MediaSources[0].Size
+		}
+	}
+	name = strings.ReplaceAll(name, "/", "／")
+	obj := model.ObjThumb{
+		Object: model.Object{
+			ID:       item.Id,
+			Name:     name,
+			Size:     size,
+			Modified: item.DateCreated,
+			Ctime:    item.DateCreated,
+			IsFolder: item.IsFolder,
+		},
+	}
+	if tag, ok := item.ImageTags["Primary"]; ok && tag != "" {
+		obj.Thumbnail.Thumbnail = fmt.Sprintf("%s/Items/%s/Images/Primary?maxWidth=400&quality=90&tag=%s",
+			d.baseURL(), item.Id, tag)
+	}
+	return &obj
+}