Re: DataChannel: how to know the max size of the sending buffer?

> JS definitely needs a unified, composable way to deal with operations
> that may queue and block; WebSockets, Datachannels, File reader/write,
etc.

That's the purpose of Stream API, based on Node.js streams and similar to
Python file-like objects and currently in specification development, bit
you can see some initial support on MediaStream API.