External deps

[alisman]

We very often want to use libraries like lodash in compute intensive routines that would be good to run in workers. Have you thought about how to solve this problem?

[developit]

Yup, that's what workerize-loader is for.

Alternatively, it would be pretty easy to add { type: 'module' } to the Worker instance here, which would enable ES Module imports in modern browsers.

[developit]

Using ES Modules is now supported in 0.1.5.

It works like this:

import workerize from 'workerize';

const worker = workerize(`
  import fetchJson from './fetcher'

  export function get(url) {
    return fetchJson(url)
  }
`, { type: 'module' });

worker.get('./some-url').then( data => {
  console.log('Response: ', data);
});

[arizonatribe]

I'm receiving an error when I attempt to implement this feature.

To troubleshoot, I rolled back to version 0.1.5 and attempted to directly mimic the example code:

// fetcher
function fetchJson(url, config = {}) {
    return fetch(url, {
        ...config,
        headers: {
            ...(config.headers || {}),
            'Content-Type': 'application/json'
        }
    }).then(response => response.json())
}

export default fetchJson

And implementing it in a worker:

const worker = workerize(`
    import fetchJson from './fetcher'

    export function get(url) {
        return fetchJson(url)
    }
`, {type: 'module'})

worker.get('https://jsonplaceholder.typicode.com/posts/1').then(data => {
    console.log('Response: ', data)
})

Yields the following error (also logging the worker to the console):

Any idea what I'm doing wrong?

[developit]

You need to use a browser that supports modules-in-Workers. I believe Chrome Canary would let you try that out.

[arizonatribe]

So standard Chrome doesn't support it?

[jpvalenciag]

@developit I'm trying to implement this but I'm getting an error in Chrome:

TypeError: Failed to construct 'Worker': Module scripts are not supported on DedicatedWorker yet.

So yeah, maybe standard Chrome doesn't support this yet. But on Firefox I'm getting a different error:

SyntaxError: import declarations may only appear at top level of a module

Do you know what could be causing it? Thanks!