Lower-level patch API

Hi,

As some may know I am experimenting with running Cycle in WebWorkers. It works pretty well, but the main bottleneck is the postMessage API. Right now I am transmitting something i call vDOMSON, representing the entire component vTree, this is then mapped recursively to snabbdom/h which in turn is passed to the patch function.

To reduce I/O I thought it could be neat to have patch in two parts, so instead of transmitting the entire vDOMSON, I can just transmit a list of mutations. The pre-patch could be run in the sub-thread, while the resulting mutations could be transferred to and applied in the main thread.

I know it sounds kind of insane.

[mightyiam]

@aronallen title change OK with you?

[staltz]

@aronallen check out snabbdom’s DOMAPI. It’s essentially a wrapper for anything that actually touches the real DOM. Perhaps you can send serializations that refer to calls of those methods.

interface DOMAPI {
  createElement: (tagName: any) => HTMLElement;
  createElementNS: (namespaceURI: string, qualifiedName: string) => Element;
  createTextNode: (text: string) => Text;
  insertBefore: (parentNode: Node, newNode: Node, referenceNode: Node | null) => void;
  removeChild: (node: Node, child: Node) => void;
  appendChild: (node: Node, child: Node) => void;
  parentNode: (node: Node) => Node;
  nextSibling: (node: Node) => Node;
  tagName: (elm: Element) => string;
  setTextContent: (node: Node, text: string | null) => void;
}

The cool thing about snabbdom is that you can pass an instance of domAPI to init().

I know some of these methods take Element as argument, but this is actually vnode.elm, so it could be that vnode.elm on the web worker side is just some kind of virtual pointer (a string, if nothing else) to an element on the DOM.

Just an idea…