script.js

// Practising with RDW Open Data

const endpointOne = 'https://opendata.rdw.nl/resource/b3us-f26s.json'; // API endpoint - Charging Points (dataset 1)
const selectedColumn = 'areaid';
// NPR dataset has also Charging POints data - Discuss if I'm going to use that dataset. It contains all my needed variables.
//          - accesspointlocation (long,lat) + PlaatsNaam is in it, but not at each place.
//          - capacity && chargingPointCapacity, but not at each place.

// Fetching data - API
fetchingData(endpointOne).then((dataRDW) => {
	const getAreaIdArray = newStringDataArray(dataRDW, selectedColumn);
	const getCapacityArray = newDataArray(dataRDW, 'capacity');
	// console.log('AreaId is:', getAreaIdArray);
	// console.log('Charging Capacity is:', getCapacityArray);
});

// Receiving data using fetch()
async function fetchingData(url) {
	try {
		const response = await fetch(url); // Waits till the data is fetched
		const data = await response.json(); // Waits till the data is formatted to JSON
		return data; // Returns the JSON data
	} catch {
		console.log(err); // Catches and shows an error when it's occurring
	}
}

// Filter and transform data - Make a new Array based on an unique key and checks if value is correct
function newDataArray(dataArray, key) {
	return dataArray.map((item) => {
		item[key] = Number(item[key]); // Makes all items from unique key a NUMBER type.

		if (item[key] <= 0) {
			// When item is lower than or equal to 0, return null
			// console.log('Negative or zero value');
			return null;
		} else {
			return item[key];
		}
	});
}

// NOT DONE YET Filter string data - Make a new Array based on an unique key and checks if value is correct
function newStringDataArray(dataArray, key) {
	return dataArray.map((item) => {
		item[key] = item[key];
		// console.log(item[key])

		if (item[key] === '') {
			console.log('Empty string');
			console.log(item);
			return null;
		} else {
			return item[key];
		}
	});
}

// Clean & Transform data
//    - transform random/incorrect data in NULL

// Combine datasets
//    - Filter out which columns I do not use