Create worker from data URI

Question

I have a very simple need, I need to spawn a webworker with a small data uri script:

new Worker('data:,console.log("HI")');

In Firefox this is giving me instead an error. Error is:

 SecurityError: Failed to load worker script at "data:,console.log("HI")"

Is there anyway to get worker to work with data URI?

Answer 1

You could definitely try Freelancer which:

• Takes a function that it transforms to a string using Function.prototype.toString
• Creates an IIFE from the passed function and passes in any additional arguments
• Transforms the function into a Blob with application/javascript as the type
• Instantiates the new worker with the data URI created with URL.createObjectURL.

Answer 2

Freelancer is equivalent to these 5 lines of code (if you don't care about error messages when your browser doesn't support Web Workers).

class Worker extends globalThis.Worker {
    constructor(fn, ...params) {
        return super(URL.createObjectURL(new Blob([`(${fn.toString()})(${params.map(JSON.stringify)})`], {type: 'application/javascript'})))
    }
}