Polling page should watch out for errors and display them

[simonw]

If an error occurs it should display that error and stop polling.

Table is being introduced here: 050612c

[simonw]

Relevant code:

datasette-extract/datasette_extract/templates/extract_progress.html

Lines 80 to 95 in f49f583

	async function pollData() {
	const response = await fetch(pollUrl);
	const data = await response.json();
	if (data && data.items && data.items.length) {
	outputElement.textContent = JSON.stringify(data.items, null, 2);
	}
	if (data.done) {
	clearInterval(pollInterval);
	const loadingSpinner = document.getElementById("loadingSpinner");
	loadingSpinner.parentNode.removeChild(loadingSpinner);
	const doneMessage = document.createElement("p");
	doneMessage.style.fontWeight = "bold";
	doneMessage.textContent = "Extraction complete!";
	outputElement.parentNode.appendChild(doneMessage);
	}
	}

[simonw]

It's actually polling an in-memory structure already which should make errors available, so no need to check the table.

[simonw]

Errors now display like this: