XMLHttpRequest upload (upload.onprogress) event is not supported

[MeetinaXD]

Hi, I noticed that #292 mentioned that interceptor has added support for the upload event of XMLHttpRequest, but I tried to use XHR to upload files in the latest version of msw, and the progress event was not triggered.

By the way, #292 mentions adding support for the progress event, but this only works in response.

I'm wondering if it's possible to add support for the progress event in upload?

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Environment

• msw: 2.3.0
• nodejs: 2.3.0
• pnpm: 9.0.6

To Reproduce

const xhr = new XMLHttpRequest()

// codes...
xhr.upload.onprogress =({ loaded, total }) => {
    console.log(loaded, total) // not triggered
};

xhr.send(someFormData)

[pantoninho]

I am experiencing the same issue. I'm using axios within a node environment and onUploadProgress is not being called either.

[kettanaito]

Hi! Thanks for raising this.

I've opened a fix at #613, and the XMLHttpRequestInterceptor now correctly emits upload events for requests with body (tested on multipart/form-data file uploads).

[!IMPORTANT] This will not be supported in JSDOM. JSDOM does not implement the upload events at all, and I always get a single progress event where both loaded and total are always 0. That is a different behavior from the browser, where the loaded and total are calculated correctly. We are going to use browser as the source of truth from now on and disregard any discrepancies JSOM may introduce. If you encounter any, please raise them with the JSDOM maintainers to provide proper implementation.

[kettanaito]

Released: v0.34.2 🎉

This has been released in v0.34.2!

• 📄 Release notes
• 📦 npm package

Make sure to always update to the latest version (npm i @mswjs/interceptors@latest) to get the newest features and bug fixes.

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Predictable release automation by @ossjs/release.

[MeetinaXD]

thank you for explaining the behavior of jsom. it works now. that's amazing and very kind of you, many thanks @kettanaito