Fetch API Stream Upload

fetch-api-stream-upload.js

let bytesUploaded = 0;

const transformStream = new TransformStream({
	transform(chunk, controller) {
		console.log('progress:', bytesUploaded / blob.size);

		bytesUploaded += chunk.byteLength;
		controller.enqueue(chunk);
	},
	flush() {
		console.log('completed');
	}
});

const response = await fetch('/upload', {
	method: 'POST',
	body: blob.stream().pipeThrough(transformStream),
	duplex: 'half',
	headers: {'Content-Type': 'application/octet-stream'}
});