The WhereBack Machine

The WhereBack Machine is a historical throw-back web application utlizing Wikipedia's "On this Day" API. On this date in history, or on the date of your choosing, learn about historical events and where those locations are in the modern world.

Code Snippet - Wikipedia Article Scrape for Geolocation

// Input link
// Output - 1) lat long in decimal (string), 2) country name (string), 3) null
function scrapeWikipedia(link) {
	return new Promise(async (res, _rej) => {
	try{
		const wikiPageBlock = await fetch(link);
		const wikiPageText = await wikiPageBlock.text();
		const parser = new DOMParser();
		const doc = parser.parseFromString(wikiPageText, "text/html");
		const infoBoxLabelList = doc.querySelectorAll(".infobox-label");
		let countryNode;
		// Checks to see if a country field exists to scrape coordinates
		infoBoxLabelList.forEach((element) => {
		if (element.textContent == "Country") {
			countryNode = element;
		}
		});
		// Option 1: Check Coordinates
		if (doc.querySelector(".geo")) {
			const coordString = doc.querySelector(".geo").textContent;
			const coordArr = coordString.split('; ')
			const lat = coordArr[0]
			const lng = coordArr[1]
			res({
				country: "",
				locationType: "coord",
				latlng: { lat, lng },
			});
		}
		// Option 2: Check Country
		else if (countryNode) {
		const countryParent = countryNode.parentNode;
		const countryParentLastChild = countryParent.lastChild;
		const country = countryParentLastChild.textContent;
		res({
			country,
			locationType: "country",
			latlng: { lat: "", lng: "" },
		});
		}
		// Option 3: Found Nothing
		else {
		res(null);
		}
	}catch (ex) {
		console.log(ex);
	}
	});
}

• github