fix(runtime): stream Python image results in chunks

Author: georgi

packages/runtime/src/providers/python-provider.ts

@@ -270,22 +270,26 @@ export class PythonProvider extends BaseProvider {
   // ── Media generation ──────────────────────────────────────────────
 
   async textToImage(params: TextToImageParams): Promise<Uint8Array> {
+    const { signal, ...wireParams } = params;
     return this._bridge.providerTextToImage(
       this._pythonProviderId,
-      { ...params },
-      this._secrets
+      { ...wireParams, model: params.model.id },
+      this._secrets,
+      signal
     );
   }
 
   async imageToImage(
     images: Uint8Array[],
     params: ImageToImageParams
   ): Promise<Uint8Array> {
+    const { signal, ...wireParams } = params;
     return this._bridge.providerImageToImage(
       this._pythonProviderId,
       images[0] ?? new Uint8Array(),
-      { ...params },
-      this._secrets
+      { ...wireParams, model: params.model.id },
+      this._secrets,
+      signal
     );
   }
 

packages/runtime/src/python-bridge-base.ts

@@ -1087,29 +1087,39 @@ export abstract class PythonBridgeBase
   async providerTextToImage(
     providerId: string,
     params: Record<string, unknown>,
-    secrets?: Record<string, string>
+    secrets?: Record<string, string>,
+    signal?: AbortSignal
   ): Promise<Uint8Array> {
-    const result = await this._providerCall("provider.text_to_image", {
-      provider: providerId,
-      params,
-      secrets: secrets ?? {}
-    });
-    return (result as { blobs: Record<string, Uint8Array> }).blobs.image;
+    const result = await this._providerBlobCall(
+      "provider.text_to_image",
+      {
+        provider: providerId,
+        params,
+        secrets: secrets ?? {}
+      },
+      signal
+    );
+    return result.blobs.image;
   }
 
   async providerImageToImage(
     providerId: string,
     image: Uint8Array,
     params: Record<string, unknown>,
-    secrets?: Record<string, string>
+    secrets?: Record<string, string>,
+    signal?: AbortSignal
   ): Promise<Uint8Array> {
-    const result = await this._providerCall("provider.image_to_image", {
-      provider: providerId,
-      image,
-      params,
-      secrets: secrets ?? {}
-    });
-    return (result as { blobs: Record<string, Uint8Array> }).blobs.image;
+    const result = await this._providerBlobCall(
+      "provider.image_to_image",
+      {
+        provider: providerId,
+        image,
+        params,
+        secrets: secrets ?? {}
+      },
+      signal
+    );
+    return result.blobs.image;
   }
 
   async providerTextToVideo(

packages/runtime/src/python-bridge-types.ts

@@ -567,13 +567,15 @@ export interface PythonBridge extends EventEmitter {
   providerTextToImage(
     providerId: string,
     params: Record<string, unknown>,
-    secrets?: Record<string, string>
+    secrets?: Record<string, string>,
+    signal?: AbortSignal
   ): Promise<Uint8Array>;
   providerImageToImage(
     providerId: string,
     image: Uint8Array,
     params: Record<string, unknown>,
-    secrets?: Record<string, string>
+    secrets?: Record<string, string>,
+    signal?: AbortSignal
   ): Promise<Uint8Array>;
   providerTextToVideo(
     providerId: string,

packages/runtime/src/swappable-python-bridge.ts

@@ -226,22 +226,25 @@ export class SwappableBridge extends EventEmitter implements PythonBridge {
   providerTextToImage(
     providerId: string,
     params: Record<string, unknown>,
-    secrets?: Record<string, string>
+    secrets?: Record<string, string>,
+    signal?: AbortSignal
   ): Promise<Uint8Array> {
-    return this._target.providerTextToImage(providerId, params, secrets);
+    return this._target.providerTextToImage(providerId, params, secrets, signal);
   }
 
   providerImageToImage(
     providerId: string,
     image: Uint8Array,
     params: Record<string, unknown>,
-    secrets?: Record<string, string>
+    secrets?: Record<string, string>,
+    signal?: AbortSignal
   ): Promise<Uint8Array> {
     return this._target.providerImageToImage(
       providerId,
       image,
       params,
-      secrets
+      secrets,
+      signal
     );
   }
 

packages/runtime/tests/python-bridge-base-coverage.test.ts

@@ -658,6 +658,10 @@ describe("PythonBridgeBase — provider RPCs", () => {
   it("providerTextToImage returns the image blob", async () => {
     const bytes = new Uint8Array([1, 2, 3]);
     const p = bridge.providerTextToImage("fal", { prompt: "x" });
+    const frame = bridge.sent.find((f) => f.type === "provider.text_to_image")!;
+    expect((frame.data as Record<string, unknown>).blob_transfer).toBe(
+      "chunked-v1"
+    );
     reply("provider.text_to_image", { blobs: { image: bytes } });
     await expect(p).resolves.toBe(bytes);
   });
@@ -670,6 +674,9 @@ describe("PythonBridgeBase — provider RPCs", () => {
       (f) => f.type === "provider.image_to_image"
     )!;
     expect((frame.data as Record<string, unknown>).image).toBe(input);
+    expect((frame.data as Record<string, unknown>).blob_transfer).toBe(
+      "chunked-v1"
+    );
     reply("provider.image_to_image", { blobs: { image: output } });
     await expect(p).resolves.toBe(output);
   });