feat: per-download downloader provider selection (#36)

Users can now pick which downloader (Aria2/qBittorrent) handles a remote
download when multiple providers are available:

- Site config exposes remote_download_providers, computed from active
  RemoteDownload-capable nodes.
- DownloadWorkflowService accepts provider and validates it against the
  live pool.
- RemoteDownloadTaskState carries provider; the task resolves it to a
  preferred node ID on first run (lowest-ID match, pool fallback when
  unmatched).
- Dialog shows a provider picker only when 2+ providers exist.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

frontend/public/locales/en-US/application.json

@@ -573,6 +573,8 @@
     "remoteDownloadHttpUser": "HTTP username (optional)",
     "remoteDownloadHttpPassword": "HTTP password (optional)",
     "remoteDownloadHeaders": "Request headers (optional)",
+    "remoteDownloadProvider": "Downloader",
+    "remoteDownloadProviderAuto": "Auto (any node)",
     "remoteDownloadHeadersDescription": "One header per line, e.g. Cookie: sid=...",
     "processNode": "Target node",
     "remoteDownloadNodeAuto": "Auto dispatch",

frontend/public/locales/zh-CN/application.json

@@ -573,6 +573,8 @@
     "remoteDownloadHttpUser": "HTTP 用户名（可选）",
     "remoteDownloadHttpPassword": "HTTP 密码（可选）",
     "remoteDownloadHeaders": "请求头（可选）",
+    "remoteDownloadProvider": "下载器",
+    "remoteDownloadProviderAuto": "自动（任意节点）",
     "remoteDownloadHeadersDescription": "每行一个请求头，例如 Cookie: sid=...",
     "processNode": "处理节点",
     "remoteDownloadNodeAuto": "自动分配",

frontend/src/api/site.ts

@@ -56,6 +56,7 @@ export interface SiteConfig {
   thumb_exts?: string[];
   show_encryption_status?: boolean;
   full_text_search?: boolean;
+  remote_download_providers?: string[];
   share_default_private?: boolean;
   default_share_links_in_profile?: string;
 }

frontend/src/api/workflow.ts

@@ -105,6 +105,7 @@ export interface DownloadWorkflowService {
   username?: string;
   password?: string;
   headers?: string[];
+  provider?: string;
 }
 
 export interface ImportWorkflowService {

frontend/src/component/FileManager/Dialogs/CreateRemoteDownload.tsx

@@ -1,4 +1,4 @@
-import { DialogContent, Stack, useMediaQuery, useTheme } from "@mui/material";
+import { DialogContent, FormControl, InputLabel, MenuItem, Select, Stack, useMediaQuery, useTheme } from "@mui/material";
 import { useSnackbar } from "notistack";
 import { useCallback, useEffect, useState } from "react";
 import { useTranslation } from "react-i18next";
@@ -19,6 +19,13 @@ import LockClosedKey from "../../Icons/LockClosedKey.tsx";
 import PersonOutlined from "../../Icons/PersonOutlined.tsx";
 import { FileManagerIndex } from "../FileManager.tsx";
 
+const providerNames: Record<string, string> = {
+  aria2: "Aria2",
+  qbittorrent: "qBittorrent",
+};
+
+const providerDisplayName = (p: string) => providerNames[p] ?? p;
+
 const CreateRemoteDownload = () => {
   const { t } = useTranslation();
   const dispatch = useAppDispatch();
@@ -33,7 +40,9 @@ const CreateRemoteDownload = () => {
   const [username, setUsername] = useState("");
   const [password, setPassword] = useState("");
   const [headers, setHeaders] = useState("");
+  const [provider, setProvider] = useState("");
 
+  const providers = useAppSelector((state) => state.siteConfig.explorer?.config?.remote_download_providers);
   const open = useAppSelector((state) => state.globalState.remoteDownloadDialogOpen);
   const target = useAppSelector((state) => state.globalState.remoteDownloadDialogFile);
   const current = useAppSelector((state) => state.fileManager[FileManagerIndex.main].pure_path);
@@ -48,6 +57,7 @@ const CreateRemoteDownload = () => {
       setUsername("");
       setPassword("");
       setHeaders("");
+      setProvider("");
     }
   }, [open]);
 
@@ -70,6 +80,7 @@ const CreateRemoteDownload = () => {
         username: username || undefined,
         password: password || undefined,
         headers: headers ? headers.split("\n").filter((h) => h.trim()) : undefined,
+        provider: provider || undefined,
       }),
     )
       .then(() => {
@@ -83,7 +94,7 @@ const CreateRemoteDownload = () => {
       .finally(() => {
         setLoading(false);
       });
-  }, [target, url, path, fileName, username, password, headers]);
+  }, [target, url, path, fileName, username, password, headers, provider]);
 
   return (
     <DraggableDialog
@@ -137,6 +148,28 @@ const CreateRemoteDownload = () => {
               fullWidth
             />
           </Stack>
+          {providers && providers.length > 1 && (
+            <Stack spacing={3} direction={isMobile ? "column" : "row"}>
+              <FormControl variant="outlined" fullWidth>
+                <InputLabel>{t("application:modals.remoteDownloadProvider")}</InputLabel>
+                <Select
+                  variant="outlined"
+                  label={t("application:modals.remoteDownloadProvider")}
+                  value={provider}
+                  onChange={(e) => setProvider(e.target.value as string)}
+                >
+                  <MenuItem value="">
+                    <em>{t("application:modals.remoteDownloadProviderAuto")}</em>
+                  </MenuItem>
+                  {providers.map((p) => (
+                    <MenuItem key={p} value={p}>
+                      {providerDisplayName(p)}
+                    </MenuItem>
+                  ))}
+                </Select>
+              </FormControl>
+            </Stack>
+          )}
           {!target && (
             <Stack spacing={3} direction={isMobile ? "column" : "row"}>
               <OutlineIconTextField

pkg/filemanager/workflows/remote_download.go

@@ -48,6 +48,9 @@ type (
 		SrcUri             string                 `json:"src_uri,omitempty"`
 		Dst                string                 `json:"dst,omitempty"`
 		FileName           string                 `json:"file_name,omitempty"`
+		// Provider pins the task to a node offering this downloader provider
+		// (e.g. "aria2"/"qbittorrent"). Empty = pool picks any capable node.
+		Provider           string                 `json:"provider,omitempty"`
 		HTTPUsername       string                 `json:"http_username,omitempty"`
 		HTTPPassword       string                 `json:"http_password,omitempty"`
 		HTTPHeaders        []string               `json:"http_headers,omitempty"`
@@ -96,6 +99,7 @@ func init() {
 // plain HTTP(S) sources.
 type RemoteDownloadTaskOption struct {
 	FileName     string
+	Provider     string
 	HTTPUsername string
 	HTTPPassword string
 	HTTPHeaders  []string
@@ -111,6 +115,7 @@ func NewRemoteDownloadTask(ctx context.Context, src string, srcFile, dst string,
 	}
 	if opts != nil {
 		state.FileName = sanitizeFileName(opts.FileName)
+		state.Provider = opts.Provider
 		state.HTTPUsername = opts.HTTPUsername
 		state.HTTPPassword = opts.HTTPPassword
 		state.HTTPHeaders = opts.HTTPHeaders
@@ -153,6 +158,12 @@ func (m *RemoteDownloadTask) Do(ctx context.Context) (task.Status, error) {
 	}
 	m.state = state
 
+	// Resolve a user-picked downloader provider to a preferred node. Runs only
+	// until a node is locked in; falls back to any capable node if no match.
+	if m.state.NodeID == 0 && m.state.Provider != "" {
+		m.state.NodeID = providerNodeID(ctx, dep, m.state.Provider)
+	}
+
 	// select node
 	node, err := allocateNode(ctx, dep, &m.state.NodeState, types.NodeCapabilityRemoteDownload)
 	if err != nil {
@@ -825,3 +836,28 @@ func sanitizeFileName(name string) string {
 	r := strings.NewReplacer("\\", "_", "/", "_", ":", "_", "*", "_", "?", "_", "\"", "_", "<", "_", ">", "_", "|", "_")
 	return r.Replace(name)
 }
+
+// providerNodeID resolves a downloader provider name to the lowest-ID active
+// node offering it for remote download. Returns 0 when no node matches, which
+// makes the pool fall back to any capable node.
+func providerNodeID(ctx context.Context, dep dependency.Dep, provider string) int {
+	nodes, err := dep.NodeClient().ListActiveNodes(ctx, nil)
+	if err != nil {
+		return 0
+	}
+	return PickProviderNode(nodes, provider)
+}
+
+func PickProviderNode(nodes []*ent.Node, provider string) int {
+	best := 0
+	for _, n := range nodes {
+		if n.Capabilities == nil || !n.Capabilities.Enabled(int(types.NodeCapabilityRemoteDownload)) ||
+			n.Settings == nil || string(n.Settings.Provider) != provider {
+			continue
+		}
+		if best == 0 || n.ID < best {
+			best = n.ID
+		}
+	}
+	return best
+}

pkg/filemanager/workflows/remote_download_test.go

@@ -5,7 +5,9 @@ import (
 	"encoding/json"
 	"testing"
 
+	"github.com/cloudreve/Cloudreve/v4/ent"
 	"github.com/cloudreve/Cloudreve/v4/inventory/types"
+	"github.com/cloudreve/Cloudreve/v4/pkg/boolset"
 	"github.com/cloudreve/Cloudreve/v4/pkg/cluster"
 	"github.com/cloudreve/Cloudreve/v4/pkg/downloader"
 	"github.com/stretchr/testify/assert"
@@ -159,3 +161,21 @@ func TestNewRemoteDownloadTaskSanitizesFileName(t *testing.T) {
 	a.NoError(json.Unmarshal([]byte(tsk.(*RemoteDownloadTask).Task.PrivateState), state))
 	a.Equal(".._.._etc_passwd", state.FileName)
 }
+
+func TestPickProviderNode(t *testing.T) {
+	caps := &boolset.BooleanSet{}
+	boolset.Set(types.NodeCapabilityRemoteDownload, true, caps)
+
+	nodes := []*ent.Node{
+		{ID: 3, Capabilities: caps, Settings: &types.NodeSetting{Provider: types.DownloaderProviderQBittorrent}},
+		{ID: 1, Capabilities: caps, Settings: &types.NodeSetting{Provider: types.DownloaderProviderAria2}},
+		{ID: 2, Capabilities: caps, Settings: &types.NodeSetting{Provider: types.DownloaderProviderAria2}},
+		{ID: 4, Capabilities: nil, Settings: &types.NodeSetting{Provider: types.DownloaderProviderAria2}},
+		{ID: 5, Capabilities: caps, Settings: nil},
+	}
+
+	assert.Equal(t, 1, PickProviderNode(nodes, string(types.DownloaderProviderAria2)))
+	assert.Equal(t, 3, PickProviderNode(nodes, string(types.DownloaderProviderQBittorrent)))
+	assert.Equal(t, 0, PickProviderNode(nodes, "deluge"))
+	assert.Equal(t, 0, PickProviderNode(nil, string(types.DownloaderProviderAria2)))
+}

service/basic/site.go

@@ -67,6 +67,10 @@ type SiteConfig struct {
 	CustomProps          []types.CustomProps        `json:"custom_props,omitempty"`
 	ShowEncryptionStatus bool                       `json:"show_encryption_status,omitempty"`
 	FullTextSearch       bool                       `json:"full_text_search,omitempty"`
+	// RemoteDownloadProviders lists distinct downloader providers offered by
+	// active remote-download-capable nodes, so clients can let users pick
+	// between e.g. Aria2 and qBittorrent per download.
+	RemoteDownloadProviders []string `json:"remote_download_providers,omitempty"`
 
 	// Thumbnail section
 	ThumbExts []string `json:"thumb_exts,omitempty"`
@@ -139,6 +143,7 @@ func (s *GetSettingService) GetSiteConfig(c *gin.Context) (*SiteConfig, error) {
 			CustomProps:          customProps,
 			ShowEncryptionStatus: showEncryptionStatus,
 			FullTextSearch:       settings.FTSEnabled(c),
+			RemoteDownloadProviders: remoteDownloadProviders(c, dep),
 		}, nil
 	case "emojis":
 		emojis := settings.EmojiPresets(c)
@@ -270,3 +275,24 @@ func GetCaptchaImage(c *gin.Context) *CaptchaResponse {
 		Ticket: idKeyD,
 	}
 }
+
+// remoteDownloadProviders returns the distinct downloader providers offered by
+// active nodes with remote-download capability, in stable sorted order.
+func remoteDownloadProviders(c *gin.Context, dep dependency.Dep) []string {
+	nodes, err := dep.NodeClient().ListActiveNodes(c, nil)
+	if err != nil {
+		return nil
+	}
+	seen := map[string]bool{}
+	var providers []string
+	for _, n := range nodes {
+		if n.Capabilities == nil || !n.Capabilities.Enabled(int(types.NodeCapabilityRemoteDownload)) ||
+			n.Settings == nil || n.Settings.Provider == "" || seen[string(n.Settings.Provider)] {
+			continue
+		}
+		seen[string(n.Settings.Provider)] = true
+		providers = append(providers, string(n.Settings.Provider))
+	}
+	sort.Strings(providers)
+	return providers
+}

service/explorer/workflows.go

@@ -81,6 +81,7 @@ type (
 		Username string   `json:"username" binding:"omitempty,max=255"`
 		Password string   `json:"password" binding:"omitempty,max=255"`
 		Headers  []string `json:"headers" binding:"omitempty,max=32,dive,max=2048"`
+		Provider string   `json:"provider" binding:"omitempty,max=64"`
 	}
 	CreateDownloadParamCtx struct{}
 )
@@ -144,9 +145,16 @@ func (service *DownloadWorkflowService) CreateDownloadTask(c *gin.Context) ([]*T
 		}
 	}
 
+	// Validate a requested downloader provider against what the node pool
+	// actually offers.
+	if service.Provider != "" && providerNodeAvailable(c, dep, service.Provider) == 0 {
+		return nil, serializer.NewError(serializer.CodeParamErr, "Invalid downloader provider", nil)
+	}
+
 	// Custom file name only applies to single-source tasks; HTTP credentials
 	// and headers only apply to plain HTTP(S) source URLs.
 	taskOpts := &workflows.RemoteDownloadTaskOption{
+		Provider:     service.Provider,
 		HTTPUsername: service.Username,
 		HTTPPassword: service.Password,
 		HTTPHeaders:  service.Headers,
@@ -679,3 +687,13 @@ func (service *BlobAuditWorkflowService) CreateBlobAuditTask(c *gin.Context) (*T
 
 	return BuildTaskResponse(t, nil, hasher), nil
 }
+
+// providerNodeAvailable returns the ID of an active remote-download node
+// offering the given provider, or 0 when none does.
+func providerNodeAvailable(c *gin.Context, dep dependency.Dep, provider string) int {
+	nodes, err := dep.NodeClient().ListActiveNodes(c, nil)
+	if err != nil {
+		return 0
+	}
+	return workflows.PickProviderNode(nodes, provider)
+}