Add realtime canvas failover config

app/(admin)/settings/admin-settings-client.tsx

@@ -846,6 +846,10 @@ export function AdminSettingsClient() {
     bflApiKey: "",
     bflBaseUrl: DEFAULT_BFL_BASE_URL,
     bflModel: DEFAULT_BFL_REALTIME_MODEL,
+    fallbackEnabled: false,
+    fallbackBflApiKey: "",
+    fallbackBflBaseUrl: DEFAULT_BFL_BASE_URL,
+    fallbackBflModel: DEFAULT_BFL_REALTIME_MODEL,
     renderMode: "balanced" as "strict-structure" | "balanced" | "stylize",
     throttleInterval: 100,
     maxBuffering: 2,
@@ -1004,6 +1008,13 @@ export function AdminSettingsClient() {
         bflApiKey?: string;
         bflBaseUrl?: string;
         bflModel?: string;
+        fallbackEnabled?: boolean;
+        fallbackBflApiKey?: string;
+        fallbackBflBaseUrl?: string;
+        fallbackBflModel?: string;
+        fallbackRunwareApiKey?: string;
+        fallbackFalApiKey?: string;
+        fallbackRunwareModel?: string;
         runwareApiKey?: string;
         falApiKey?: string;
         runwareModel?: string;
@@ -1024,6 +1035,15 @@ export function AdminSettingsClient() {
         bflApiKey: config.bflApiKey || config.runwareApiKey || config.falApiKey || "",
         bflBaseUrl: config.bflBaseUrl || DEFAULT_BFL_BASE_URL,
         bflModel: config.bflModel || config.runwareModel || DEFAULT_BFL_REALTIME_MODEL,
+        fallbackEnabled: config.fallbackEnabled === true,
+        fallbackBflApiKey:
+          config.fallbackBflApiKey ||
+          config.fallbackRunwareApiKey ||
+          config.fallbackFalApiKey ||
+          "",
+        fallbackBflBaseUrl: config.fallbackBflBaseUrl || DEFAULT_BFL_BASE_URL,
+        fallbackBflModel:
+          config.fallbackBflModel || config.fallbackRunwareModel || DEFAULT_BFL_REALTIME_MODEL,
         renderMode:
           config.renderMode === "strict-structure" || config.renderMode === "stylize"
             ? config.renderMode
@@ -2060,12 +2080,23 @@ export function AdminSettingsClient() {
       const bflApiKey = realtimeCanvasConfig.bflApiKey.trim();
       const bflBaseUrl = realtimeCanvasConfig.bflBaseUrl.trim() || DEFAULT_BFL_BASE_URL;
       const bflModel = realtimeCanvasConfig.bflModel.trim() || DEFAULT_BFL_REALTIME_MODEL;
+      const fallbackEnabled = realtimeCanvasConfig.fallbackEnabled;
+      const fallbackBflApiKey = realtimeCanvasConfig.fallbackBflApiKey.trim();
+      const fallbackBflBaseUrl =
+        realtimeCanvasConfig.fallbackBflBaseUrl.trim() || DEFAULT_BFL_BASE_URL;
+      const fallbackBflModel =
+        realtimeCanvasConfig.fallbackBflModel.trim() || DEFAULT_BFL_REALTIME_MODEL;
 
       if (realtimeCanvasConfig.enabled && !bflApiKey) {
         toast.error("启用实时画布功能需要配置 BFL API Key");
         return;
       }
 
+      if (realtimeCanvasConfig.enabled && fallbackEnabled && !fallbackBflApiKey) {
+        toast.error("启用备用实时服务需要配置备用 BFL API Key");
+        return;
+      }
+
       if (realtimeCanvasConfig.enabled) {
         const probeResponse = await fetch("/api/admin/realtime/model-capability", {
           method: "POST",
@@ -2081,6 +2112,23 @@ export function AdminSettingsClient() {
           toast.error(probeData?.message || "模型能力探针失败，已阻止保存");
           return;
         }
+
+        if (fallbackEnabled) {
+          const fallbackProbeResponse = await fetch("/api/admin/realtime/model-capability", {
+            method: "POST",
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify({
+              apiKey: fallbackBflApiKey,
+              modelId: fallbackBflModel,
+              baseUrl: fallbackBflBaseUrl,
+            }),
+          });
+          const fallbackProbeData = await fallbackProbeResponse.json().catch(() => null);
+          if (!fallbackProbeResponse.ok || fallbackProbeData?.supported === false) {
+            toast.error(fallbackProbeData?.message || "备用实时服务探针失败，已阻止保存");
+            return;
+          }
+        }
       }
 
       const response = await fetch("/api/admin/settings", {
@@ -2093,6 +2141,10 @@ export function AdminSettingsClient() {
             bflApiKey,
             bflBaseUrl,
             bflModel,
+            fallbackEnabled,
+            fallbackBflApiKey,
+            fallbackBflBaseUrl,
+            fallbackBflModel,
             runwareApiKey: bflApiKey,
             falApiKey: bflApiKey,
             runwareModel: bflModel,
@@ -8595,6 +8647,73 @@ export function AdminSettingsClient() {
                 />
               </div>
 
+              <div className="rounded-lg border border-dashed p-4 space-y-4">
+                <div className="flex items-center justify-between">
+                  <div className="space-y-0.5">
+                    <Label className="text-base">备用实时服务</Label>
+                    <div className="text-sm text-muted-foreground">
+                      主实时服务失败时自动切换到备用 BFL 服务。
+                    </div>
+                  </div>
+                  <Switch
+                    checked={realtimeCanvasConfig.fallbackEnabled}
+                    onCheckedChange={(checked) =>
+                      setRealtimeCanvasConfig({ ...realtimeCanvasConfig, fallbackEnabled: checked })
+                    }
+                    disabled={!realtimeCanvasConfig.enabled}
+                  />
+                </div>
+
+                <div className="space-y-2">
+                  <Label htmlFor="realtimeFallbackBflApiKey">备用 BFL API Key</Label>
+                  <Input
+                    id="realtimeFallbackBflApiKey"
+                    type="password"
+                    value={realtimeCanvasConfig.fallbackBflApiKey}
+                    onChange={(e) =>
+                      setRealtimeCanvasConfig({
+                        ...realtimeCanvasConfig,
+                        fallbackBflApiKey: e.target.value,
+                      })
+                    }
+                    placeholder="bfl_xxxxxxxxxxxxx"
+                    disabled={!realtimeCanvasConfig.enabled || !realtimeCanvasConfig.fallbackEnabled}
+                  />
+                </div>
+
+                <div className="space-y-2">
+                  <Label htmlFor="realtimeFallbackBflBaseUrl">备用 BFL API Base URL</Label>
+                  <Input
+                    id="realtimeFallbackBflBaseUrl"
+                    value={realtimeCanvasConfig.fallbackBflBaseUrl}
+                    onChange={(e) =>
+                      setRealtimeCanvasConfig({
+                        ...realtimeCanvasConfig,
+                        fallbackBflBaseUrl: e.target.value,
+                      })
+                    }
+                    placeholder={DEFAULT_BFL_BASE_URL}
+                    disabled={!realtimeCanvasConfig.enabled || !realtimeCanvasConfig.fallbackEnabled}
+                  />
+                </div>
+
+                <div className="space-y-2">
+                  <Label htmlFor="realtimeFallbackBflModel">备用 FLUX.2 模型 ID</Label>
+                  <Input
+                    id="realtimeFallbackBflModel"
+                    value={realtimeCanvasConfig.fallbackBflModel}
+                    onChange={(e) =>
+                      setRealtimeCanvasConfig({
+                        ...realtimeCanvasConfig,
+                        fallbackBflModel: e.target.value,
+                      })
+                    }
+                    placeholder={DEFAULT_BFL_REALTIME_MODEL}
+                    disabled={!realtimeCanvasConfig.enabled || !realtimeCanvasConfig.fallbackEnabled}
+                  />
+                </div>
+              </div>
+
               <div className="grid grid-cols-1 gap-4">
                 <div className="space-y-2">
                   <Label>实时渲染模式</Label>

app/api/admin/settings/route.ts

@@ -7,15 +7,16 @@ import {
 } from "@/lib/db/queries";
 import { ChatSDKError } from "@/lib/errors";
 import { probeBflModelSupport } from "@/lib/realtime/bfl-capability";
+import {
+  normalizeRealtimeCanvasConfigForStorage,
+  resolveRealtimeProviders,
+} from "@/lib/realtime/config";
 
 const settingSchema = z.object({
   key: z.string(),
   value: z.any(),
 });
 
-const DEFAULT_BFL_MODEL = "flux-2-klein-4b";
-const DEFAULT_BFL_BASE_URL = "https://api.bfl.ai";
-
 function isObjectLike(value: unknown): value is Record<string, unknown> {
   return Boolean(value) && typeof value === "object" && !Array.isArray(value);
 }
@@ -62,49 +63,34 @@ export async function POST(request: Request) {
       }
 
       const enabled = value.enabled !== false;
-      const bflApiKey = String(
+      const normalizedValue = normalizeRealtimeCanvasConfigForStorage(value);
-        value.bflApiKey || value.runwareApiKey || value.falApiKey || value.apiKey || ""
+      const providers = resolveRealtimeProviders(normalizedValue);
-      ).trim();
-      const bflModel = String(value.bflModel || value.runwareModel || DEFAULT_BFL_MODEL).trim() || DEFAULT_BFL_MODEL;
-      const bflBaseUrl = String(value.bflBaseUrl || DEFAULT_BFL_BASE_URL).trim() || DEFAULT_BFL_BASE_URL;
-      const renderMode =
-        value.renderMode === "strict-structure" ||
-        value.renderMode === "stylize" ||
-        value.renderMode === "balanced"
-          ? value.renderMode
-          : "balanced";
 
       if (enabled) {
-        if (!bflApiKey) {
+        if (providers.length === 0) {
-          return new ChatSDKError("bad_request:api", "启用实时画布必须配置 BFL API Key").toResponse();
+          return new ChatSDKError("bad_request:api", "启用实时画布必须至少配置一个可用服务").toResponse();
         }
-        const probeResult = await probeBflModelSupport({
+
-          apiKey: bflApiKey,
+        for (const provider of providers) {
-          modelId: bflModel,
+          const probeResult = await probeBflModelSupport({
-          baseUrl: bflBaseUrl,
+            apiKey: provider.apiKey,
-        });
+            modelId: provider.model,
-        if (!probeResult.supported) {
+            baseUrl: provider.baseUrl,
-          return Response.json(
+          });
-            {
+
-              code: probeResult.code,
+          if (!probeResult.supported) {
-              message: probeResult.message,
+            return Response.json(
-            },
+              {
-            { status: mapProbeStatus(probeResult.code) }
+                code: probeResult.code,
-          );
+                message: `${provider.label}校验失败：${probeResult.message}`,
+              },
+              { status: mapProbeStatus(probeResult.code) }
+            );
+          }
         }
       }
 
-      nextValue = {
+      nextValue = normalizedValue;
-        ...value,
-        bflApiKey,
-        bflModel,
-        bflBaseUrl,
-        runwareApiKey: bflApiKey,
-        falApiKey: bflApiKey,
-        apiKey: bflApiKey,
-        runwareModel: bflModel,
-        renderMode,
-      };
     }
 
     const setting = await upsertSystemSetting({

app/api/realtime/config/route.ts

@@ -1,30 +1,10 @@
 import { auth } from "@/app/(auth)/auth";
 import { getSystemSetting } from "@/lib/db/queries";
-
+import {
-type RealtimeCanvasConfig = {
+  DEFAULT_BFL_BASE_URL,
-  enabled?: boolean;
+  RealtimeCanvasConfig,
-  bflApiKey?: string;
+  resolveRealtimeProviders,
-  bflModel?: string;
+} from "@/lib/realtime/config";
-  bflBaseUrl?: string;
-  runwareApiKey?: string;
-  runwareModel?: string;
-  renderMode?: "strict-structure" | "balanced" | "stylize";
-  falApiKey?: string;
-  apiKey?: string;
-  strictSketch?: boolean;
-  throttleInterval?: number;
-  maxBuffering?: number;
-  maxInputResolution?: number;
-  jpegQuality?: number;
-  defaults?: {
-    steps?: number;
-    cfgScale?: number;
-    strength?: number;
-    scheduleMu?: number;
-    feedback?: number;
-    imageSize?: "square" | "square_hd";
-  };
-};
 
 const defaultConfig = {
   session: {
@@ -78,21 +58,14 @@ export async function GET() {
     );
   }
 
-  const bflApiKey = String(
+  const providers = resolveRealtimeProviders(config);
-    config.bflApiKey ||
+  const activeProvider = providers[0];
-      config.runwareApiKey ||
-      config.falApiKey ||
-      config.apiKey ||
-      process.env.BFL_API_KEY ||
-      process.env.BFL_KEY ||
-      ""
-  ).trim();
 
-  if (!bflApiKey) {
+  if (!activeProvider) {
     return Response.json(
       {
         code: "BFL_KEY_MISSING",
-        message: "未配置 BFL API Key（请在服务器环境变量或设置中配置）",
+        message: "未配置可用的实时画布服务（请在服务器环境变量或设置中配置）",
       },
       { status: 500 }
     );
@@ -139,21 +112,24 @@ export async function GET() {
     defaultConfig.model.limits.strength.max
   );
   const imageSize = config.defaults?.imageSize === "square_hd" ? "square_hd" : "square";
-  const modelId = String(
+  const modelId = activeProvider.model;
-    config.bflModel ||
-      config.runwareModel ||
-      process.env.BFL_MODEL ||
-      process.env.RUNWARE_MODEL ||
-      defaultConfig.model.id
-  ).trim();
 
   return Response.json({
     ...defaultConfig,
     provider: {
       type: "bfl",
-      baseUrl:
+      baseUrl: activeProvider.baseUrl || DEFAULT_BFL_BASE_URL,
-        String(config.bflBaseUrl || process.env.BFL_BASE_URL || "https://api.bfl.ai").trim() ||
+    },
-        "https://api.bfl.ai",
+    failover: {
+      enabled: providers.length > 1,
+      fallbackProvider:
+        providers.length > 1
+          ? {
+              type: "bfl",
+              baseUrl: providers[1].baseUrl,
+              model: providers[1].model,
+            }
+          : null,
     },
     transport: {
       throttleInterval,

app/api/realtime/generate/route.ts

@@ -1,18 +1,11 @@
 import { auth } from "@/app/(auth)/auth";
 import { getSystemSetting } from "@/lib/db/queries";
-
+import {
-type RealtimeCanvasConfig = {
+  DEFAULT_BFL_MODEL,
-  enabled?: boolean;
+  RealtimeCanvasConfig,
-  bflApiKey?: string;
+  RealtimeProviderConfig,
-  bflModel?: string;
+  resolveRealtimeProviders,
-  bflBaseUrl?: string;
+} from "@/lib/realtime/config";
-  runwareApiKey?: string;
-  runwareModel?: string;
-  falApiKey?: string;
-  apiKey?: string;
-  negativePrompt?: string;
-  maxInputResolution?: number;
-};
 
 type GeneratePayload = {
   requestId?: string;
@@ -48,8 +41,6 @@ type BflSubmitResponse = {
 
 const FALLBACK_REALTIME_PROMPT =
   "严格按照输入草图生成：保持主体轮廓、位置、比例和数量一致，只做材质与光影细化；禁止改变构图，禁止新增无关背景纹理。";
-const DEFAULT_BFL_BASE_URL = "https://api.bfl.ai";
-const DEFAULT_BFL_MODEL = "flux-2-klein-4b";
 
 function clamp(value: number, min: number, max: number) {
   return Math.min(max, Math.max(min, value));
@@ -72,11 +63,6 @@ function resolveSeed(seed: unknown) {
   return normalized;
 }
 
-function normalizeBaseUrl(raw: string | undefined) {
-  const next = String(raw || DEFAULT_BFL_BASE_URL).trim();
-  return (next || DEFAULT_BFL_BASE_URL).replace(/\/+$/, "");
-}
-
 function encodeModelPath(modelId: string) {
   return modelId
     .split("/")
@@ -168,6 +154,22 @@ type SubmitTaskResult = {
   status: number;
 };
 
+type ProviderAttemptResult =
+  | {
+      ok: true;
+      imageUrl: string;
+      taskId: string;
+      imageField: "input_image" | "image_prompt";
+      fallbackWarning: string;
+      provider: RealtimeProviderConfig;
+    }
+  | {
+      ok: false;
+      message: string;
+      status: number;
+      provider: RealtimeProviderConfig;
+    };
+
 async function submitBflTask(params: {
   apiKey: string;
   baseUrl: string;
@@ -290,6 +292,97 @@ async function pollBflResult(params: {
   };
 }
 
+async function generateWithProvider(params: {
+  provider: RealtimeProviderConfig;
+  imagePrompt: string;
+  prompt: string;
+  size: number;
+  seed?: number;
+}): Promise<ProviderAttemptResult> {
+  const imageFieldCandidates = getBflImageFieldCandidates();
+
+  let selectedImageField: "input_image" | "image_prompt" = imageFieldCandidates[0];
+  let submitResult: SubmitTaskResult | null = null;
+  let fallbackWarning = "";
+
+  for (let index = 0; index < imageFieldCandidates.length; index += 1) {
+    selectedImageField = imageFieldCandidates[index];
+    const requestBody: Record<string, unknown> = {
+      prompt: params.prompt,
+      width: params.size,
+      height: params.size,
+      output_format: "jpeg",
+      safety_tolerance: 2,
+      [selectedImageField]: params.imagePrompt,
+      ...(typeof params.seed === "number" ? { seed: params.seed } : {}),
+    };
+
+    submitResult = await submitBflTask({
+      apiKey: params.provider.apiKey,
+      baseUrl: params.provider.baseUrl,
+      model: params.provider.model,
+      body: requestBody,
+    });
+
+    if (!submitResult.errorMessage) {
+      break;
+    }
+
+    if (
+      index < imageFieldCandidates.length - 1 &&
+      shouldRetryWithAlternateImageField(submitResult.errorMessage)
+    ) {
+      fallbackWarning = "模型参数兼容性已自动切换，继续生成。";
+      continue;
+    }
+
+    return {
+      ok: false,
+      message: submitResult.errorMessage || "实时生成提交失败",
+      status: submitResult.status || 502,
+      provider: params.provider,
+    };
+  }
+
+  if (!submitResult) {
+    return {
+      ok: false,
+      message: "实时生成提交失败",
+      status: 502,
+      provider: params.provider,
+    };
+  }
+
+  let finalImageUrl = submitResult.imageUrl;
+  if (!finalImageUrl) {
+    const pollResult = await pollBflResult({
+      apiKey: params.provider.apiKey,
+      baseUrl: params.provider.baseUrl,
+      pollingUrl: submitResult.pollingUrl,
+      taskId: submitResult.taskId,
+      timeoutMs: 110_000,
+    });
+    if (!pollResult.imageUrl) {
+      return {
+        ok: false,
+        message: pollResult.errorMessage || "实时生成未返回图像",
+        status: pollResult.status || 502,
+        provider: params.provider,
+      };
+    }
+    finalImageUrl = pollResult.imageUrl;
+  }
+
+  return {
+    ok: true,
+    imageUrl: finalImageUrl,
+    taskId: submitResult.taskId,
+    imageField: selectedImageField,
+    fallbackWarning,
+    provider: params.provider,
+  };
+}
+
 export async function POST(request: Request) {
   const session = await auth();
   if (!session?.user?.id) {
@@ -318,33 +411,17 @@ export async function POST(request: Request) {
     );
   }
 
-  const bflApiKey = String(
+  const providers = resolveRealtimeProviders(config);
-    config.bflApiKey ||
+  if (providers.length === 0) {
-      config.runwareApiKey ||
-      config.falApiKey ||
-      config.apiKey ||
-      process.env.BFL_API_KEY ||
-      process.env.BFL_KEY ||
-      ""
-  ).trim();
-  if (!bflApiKey) {
     return Response.json(
       {
         code: "BFL_KEY_MISSING",
-        message: "未配置 BFL API Key",
+        message: "未配置可用的实时画布服务",
       },
       { status: 500 }
     );
   }
 
-  const model = String(
-    config.bflModel ||
-      config.runwareModel ||
-      process.env.BFL_MODEL ||
-      process.env.RUNWARE_MODEL ||
-      DEFAULT_BFL_MODEL
-  ).trim() || DEFAULT_BFL_MODEL;
-  const baseUrl = normalizeBaseUrl(config.bflBaseUrl || process.env.BFL_BASE_URL);
   const maxInputResolution = clamp(Number(config.maxInputResolution || 1024), 512, 1536);
   const size = resolveSquareSize(body.imageSize, maxInputResolution);
   const seed = resolveSeed(body.seed);
@@ -373,100 +450,69 @@ export async function POST(request: Request) {
     );
   }
 
-  const imageFieldCandidates = getBflImageFieldCandidates();
+  const providerErrors: string[] = [];
 
-  let selectedImageField: "input_image" | "image_prompt" = imageFieldCandidates[0];
+  for (const provider of providers) {
-  let submitResult: SubmitTaskResult | null = null;
+    const result = await generateWithProvider({
-  let fallbackWarning = "";
+      provider,
-
+      imagePrompt,
-  for (let index = 0; index < imageFieldCandidates.length; index += 1) {
-    selectedImageField = imageFieldCandidates[index];
-    const requestBody: Record<string, unknown> = {
       prompt: positivePrompt,
-      width: size,
+      size,
-      height: size,
+      seed,
-      output_format: "jpeg",
-      safety_tolerance: 2,
-      [selectedImageField]: imagePrompt,
-      ...(typeof seed === "number" ? { seed } : {}),
-    };
-
-    submitResult = await submitBflTask({
-      apiKey: bflApiKey,
-      baseUrl,
-      model,
-      body: requestBody,
     });
 
-    if (!submitResult.errorMessage) {
+    if (!result.ok) {
-      break;
+      providerErrors.push(`${provider.label}（${provider.baseUrl}）: ${result.message}`);
-    }
-
-    if (index < imageFieldCandidates.length - 1 && shouldRetryWithAlternateImageField(submitResult.errorMessage)) {
-      fallbackWarning = "模型参数兼容性已自动切换，继续生成。";
       continue;
     }
 
-    break;
+    const warningParts = [result.fallbackWarning];
-  }
+    if (result.provider.source === "fallback") {
-
+      warningParts.push("主实时服务异常，已自动切换到备用服务。");
-  if (!submitResult || submitResult.errorMessage) {
-    return Response.json(
-      {
-        code: "BFL_REQUEST_FAILED",
-        message: submitResult?.errorMessage || "BFL 请求失败",
-      },
-      { status: 502 }
-    );
-  }
-
-  let finalImageUrl = submitResult.imageUrl;
-  if (!finalImageUrl) {
-    const pollResult = await pollBflResult({
-      apiKey: bflApiKey,
-      baseUrl,
-      pollingUrl: submitResult.pollingUrl,
-      taskId: submitResult.taskId,
-      timeoutMs: 110_000,
-    });
-    if (!pollResult.imageUrl) {
-      return Response.json(
-        {
-          code: "BFL_EMPTY_OUTPUT",
-          message: pollResult.errorMessage || "BFL 未返回图像",
-        },
-        { status: 502 }
-      );
     }
-    finalImageUrl = pollResult.imageUrl;
+    const warning = warningParts.filter(Boolean).join(" ");
+
+    console.log("[RealtimeBFL] frame success", {
+      userId: session.user.id,
+      requestId: body.requestId || null,
+      model: result.provider.model || DEFAULT_BFL_MODEL,
+      providerSource: result.provider.source,
+      providerBaseUrl: result.provider.baseUrl,
+      taskId: result.taskId || null,
+      hasPrompt: Boolean(rawPrompt && rawPrompt !== FALLBACK_REALTIME_PROMPT),
+      imageField: result.imageField,
+      qualityProfile: body.qualityProfile || "refine",
+      size,
+      roi: body.roi || null,
+      hasMask: Boolean(body.maskImageUrl),
+      warning: warning || null,
+    });
+
+    return Response.json({
+      ok: true,
+      provider: "bfl",
+      providerSource: result.provider.source,
+      model: result.provider.model,
+      transport: "http-poll",
+      taskUUID: result.taskId || undefined,
+      imageDataURI: result.imageUrl.startsWith("data:")
+        ? result.imageUrl
+        : !/^https?:\/\//i.test(result.imageUrl)
+          ? `data:image/jpeg;base64,${result.imageUrl}`
+          : undefined,
+      imageUrl: /^https?:\/\//i.test(result.imageUrl) ? result.imageUrl : undefined,
+      warning: warning || undefined,
+    });
   }
 
-  console.log("[RealtimeBFL] frame success", {
+  return Response.json(
-    userId: session.user.id,
+    {
-    requestId: body.requestId || null,
+      code: "BFL_REQUEST_FAILED",
-    model,
+      message:
-    taskId: submitResult.taskId || null,
+        providerErrors.length > 0
-    hasPrompt: Boolean(rawPrompt && rawPrompt !== FALLBACK_REALTIME_PROMPT),
+          ? `主备用实时服务均不可用：${providerErrors.join("；")}`
-    imageField: selectedImageField,
+          : "实时生成失败",
-    qualityProfile: body.qualityProfile || "refine",
+    },
-    size,
+    { status: 502 }
-    roi: body.roi || null,
+  );
-    hasMask: Boolean(body.maskImageUrl),
-    warning: fallbackWarning || null,
-  });
-
-  return Response.json({
-    ok: true,
-    provider: "bfl",
-    model,
-    transport: "http-poll",
-    taskUUID: submitResult.taskId || undefined,
-    imageDataURI: finalImageUrl.startsWith("data:")
-      ? finalImageUrl
-      : !/^https?:\/\//i.test(finalImageUrl)
-        ? `data:image/jpeg;base64,${finalImageUrl}`
-        : undefined,
-    imageUrl: /^https?:\/\//i.test(finalImageUrl) ? finalImageUrl : undefined,
-    warning: fallbackWarning || undefined,
-  });
 }

lib/realtime/config.ts

@@ -0,0 +1,186 @@
+export const DEFAULT_BFL_MODEL = "flux-2-klein-4b";
+export const DEFAULT_BFL_BASE_URL = "https://api.bfl.ai";
+
+export type RealtimeCanvasConfig = {
+  enabled?: boolean;
+  bflApiKey?: string;
+  bflModel?: string;
+  bflBaseUrl?: string;
+  runwareApiKey?: string;
+  runwareModel?: string;
+  falApiKey?: string;
+  apiKey?: string;
+  fallbackEnabled?: boolean;
+  fallbackBflApiKey?: string;
+  fallbackBflModel?: string;
+  fallbackBflBaseUrl?: string;
+  fallbackRunwareApiKey?: string;
+  fallbackRunwareModel?: string;
+  fallbackFalApiKey?: string;
+  fallbackApiKey?: string;
+  negativePrompt?: string;
+  renderMode?: "strict-structure" | "balanced" | "stylize";
+  strictSketch?: boolean;
+  throttleInterval?: number;
+  maxBuffering?: number;
+  maxInputResolution?: number;
+  jpegQuality?: number;
+  defaults?: {
+    steps?: number;
+    cfgScale?: number;
+    strength?: number;
+    scheduleMu?: number;
+    feedback?: number;
+    imageSize?: "square" | "square_hd";
+  };
+};
+
+export type RealtimeProviderConfig = {
+  apiKey: string;
+  baseUrl: string;
+  model: string;
+  source: "primary" | "fallback";
+  label: string;
+};
+
+function trimString(value: unknown) {
+  return String(value || "").trim();
+}
+
+export function normalizeBaseUrl(raw: string | undefined) {
+  const next = trimString(raw || DEFAULT_BFL_BASE_URL);
+  return (next || DEFAULT_BFL_BASE_URL).replace(/\/+$/, "");
+}
+
+function hasFallbackIntent(config: RealtimeCanvasConfig) {
+  if (config.fallbackEnabled === true) return true;
+  if (config.fallbackEnabled === false) return false;
+
+  return Boolean(
+    trimString(
+      config.fallbackBflApiKey ||
+        config.fallbackRunwareApiKey ||
+        config.fallbackFalApiKey ||
+        config.fallbackApiKey ||
+        config.fallbackBflBaseUrl ||
+        config.fallbackBflModel ||
+        config.fallbackRunwareModel
+    )
+  );
+}
+
+export function resolvePrimaryRealtimeProvider(
+  config: RealtimeCanvasConfig,
+  env: NodeJS.ProcessEnv = process.env
+): RealtimeProviderConfig | null {
+  const apiKey = trimString(
+    config.bflApiKey ||
+      config.runwareApiKey ||
+      config.falApiKey ||
+      config.apiKey ||
+      env.BFL_API_KEY ||
+      env.BFL_KEY
+  );
+  if (!apiKey) return null;
+
+  const model =
+    trimString(config.bflModel || config.runwareModel || env.BFL_MODEL || env.RUNWARE_MODEL) ||
+    DEFAULT_BFL_MODEL;
+  const baseUrl = normalizeBaseUrl(config.bflBaseUrl || env.BFL_BASE_URL);
+
+  return {
+    apiKey,
+    model,
+    baseUrl,
+    source: "primary",
+    label: "主实时服务",
+  };
+}
+
+export function resolveFallbackRealtimeProvider(
+  config: RealtimeCanvasConfig
+): RealtimeProviderConfig | null {
+  if (!hasFallbackIntent(config)) return null;
+
+  const apiKey = trimString(
+    config.fallbackBflApiKey ||
+      config.fallbackRunwareApiKey ||
+      config.fallbackFalApiKey ||
+      config.fallbackApiKey
+  );
+  if (!apiKey) return null;
+
+  const model =
+    trimString(config.fallbackBflModel || config.fallbackRunwareModel) || DEFAULT_BFL_MODEL;
+  const baseUrl = normalizeBaseUrl(config.fallbackBflBaseUrl || DEFAULT_BFL_BASE_URL);
+
+  return {
+    apiKey,
+    model,
+    baseUrl,
+    source: "fallback",
+    label: "备用实时服务",
+  };
+}
+
+export function resolveRealtimeProviders(
+  config: RealtimeCanvasConfig,
+  env: NodeJS.ProcessEnv = process.env
+) {
+  const providers: RealtimeProviderConfig[] = [];
+  const primary = resolvePrimaryRealtimeProvider(config, env);
+  const fallback = resolveFallbackRealtimeProvider(config);
+
+  if (primary) {
+    providers.push(primary);
+  }
+
+  if (
+    fallback &&
+    !providers.some(
+      (provider) =>
+        provider.apiKey === fallback.apiKey &&
+        provider.baseUrl === fallback.baseUrl &&
+        provider.model === fallback.model
+    )
+  ) {
+    providers.push(fallback);
+  }
+
+  return providers;
+}
+
+export function normalizeRealtimeCanvasConfigForStorage(
+  value: Record<string, unknown>,
+  env: NodeJS.ProcessEnv = process.env
+): RealtimeCanvasConfig {
+  const renderMode =
+    value.renderMode === "strict-structure" ||
+    value.renderMode === "stylize" ||
+    value.renderMode === "balanced"
+      ? value.renderMode
+      : "balanced";
+
+  const primary = resolvePrimaryRealtimeProvider(value as RealtimeCanvasConfig, env);
+  const fallback = resolveFallbackRealtimeProvider(value as RealtimeCanvasConfig);
+
+  return {
+    ...value,
+    bflApiKey: primary?.apiKey || "",
+    bflModel: primary?.model || DEFAULT_BFL_MODEL,
+    bflBaseUrl: primary?.baseUrl || normalizeBaseUrl(env.BFL_BASE_URL),
+    runwareApiKey: primary?.apiKey || "",
+    falApiKey: primary?.apiKey || "",
+    apiKey: primary?.apiKey || "",
+    runwareModel: primary?.model || DEFAULT_BFL_MODEL,
+    fallbackEnabled: Boolean(fallback),
+    fallbackBflApiKey: fallback?.apiKey || "",
+    fallbackBflModel: fallback?.model || DEFAULT_BFL_MODEL,
+    fallbackBflBaseUrl: fallback?.baseUrl || DEFAULT_BFL_BASE_URL,
+    fallbackRunwareApiKey: fallback?.apiKey || "",
+    fallbackFalApiKey: fallback?.apiKey || "",
+    fallbackApiKey: fallback?.apiKey || "",
+    fallbackRunwareModel: fallback?.model || DEFAULT_BFL_MODEL,
+    renderMode,
+  };
+}