Fetching CJS plugin on desktop - worker support?

[cmdcolin]

I noticed that our rpcWorker does not provide a 'fetchCJS' callback, and the fetchCJS callback in place uses window.require so just adding it with a copy of the current one may not work. But, if fetchCJS is helpful/needed in jbrowse-desktop on a webworker, we may want to remedy this?

[cmdcolin]

wanted to see what you thought of this one @garrettjstevens

[garrettjstevens]

The existing fetchCJS won't work in the webworker since there is no window, but with a small adjustment to replace window with globalThis, I think it will work.

One concern that I just learned about, though, is that native Node.js modules are not thread-safe, and electron strongly recommends not using them in web workers. We already use native node modules in the workers, though, e.g. when we use fs in LocalFile from generic-filehandle when doing openLocation on a worker thread. So this wouldn't be a new risk, but still could be something to consider.

[rbuels]

We already use native node modules in the workers, though, e.g. when we use fs in LocalFile from generic-filehandle when doing openLocation on a worker thread. So this wouldn't be a new risk, but still could be something to consider.

Above that, however, it does at least say that "All built-in modules of Node.js are supported in Web Workers", so I think our use of fs is probably ok.