Support streaming images via AsyncGenerator in `createStableDiffusionImages`

[skirsten]

It would be great if the interface would support streaming images using AsyncGenerator.

E.g.

createStableDiffusionImages: async function* (options) {
  const image = await fetch(`${window.location.origin}/DummyImage.png`);
  const blob = await image.blob();
  const createdAt = new Date();

  for (let i = 0; i < (options?.count || 4); i++) {
    yield {
      id: `${Math.random() * 10000000}`,
      createdAt,
      blob,
    };

    set(({ imagesGeneratedSoFar }) => ({
      imagesGeneratedSoFar: imagesGeneratedSoFar + 1,
    }));

    await new Promise((resolve) => setTimeout(resolve, 1000));
  }
},

The type could look something like:

createStableDiffusionImages?: (options?: {
  /** The `StableDiffusionInput` you've been asked to generate, if empty, you could still return a random image */
  input?: StableDiffusionInput;
  /** Determines how many images will be created using the given `StableDiffusionInput` */
  count?: number;
}) =>
  | MaybePromise<StableDiffusionImages | undefined>
  | AsyncGenerator<StableDiffusionImage>;

to support both flows.

What do you think?

[cruhl]

I definitely want to support streaming images.

The contract for plugins is really sticky and important to get right, so I'm a bit leery about adding anything without a working implementation.

Maybe we can get this implemented with the Stability plugin or the open PR for the webui plugin?