Simple vCard JavaScript parser.

parse-vcf.js

/* Usage:
 * require() as module, use as parseVCF(contents, debug = false): JSON
 * node index.js json < input.vcf > output.json
 * node index.js < input.vcf > output.csv
 */

function parseVCF(contents, debug = false) {
	// Unfold
	contents = contents.replace(/([\n\r]{1,2}) /g, '')
	contents = contents.replace(/=([\n\r]{1,2})=/g, '=')
	contents = contents.replace(/=([\n\r]{1,2})([\n\r]{1,2})/g, '$1')

	// Match contacts
	let contacts = contents.match(/BEGIN:VCARD(.|\s)*?END:VCARD/g);
	debug && console.error("Found contacts: " + contacts.length);

	return contacts.map(str => str
		.replace(/\s*(BEGIN|END):VCARD\s*/g, '')
		.split(/\s*[\n\r]{1,2}\s*/)
		.map(prop => {
			let resp = prop.match(/^([^:]+):(.*)/);
			if(resp == null) {
				debug && console.error("Something went wrong...");
				return {};
			}

			// Extract meta
	        let meta = {};
			resp[1].split(";")
				.map(function (p, i) {
					let match = p.match(/([a-z]+)=(.*)/i);
					if (match) {
						return [match[1], match[2]];
					} else {
						return ["TYPE" + (i === 0 ? "" : i), p];
					}
				})
				.forEach(function (p) {
					meta[p[0]] = p[1];
				});

			let value = resp[2];

			// QUOTED-PRINTABLE decoding.
			if(meta.ENCODING == "QUOTED-PRINTABLE" && meta.CHARSET == "UTF-8"){
				delete meta.ENCODING;
				delete meta.CHARSET;

				value = value.replace(/([=a-fA-F0-9]+)/g, function(_, chain) {
					if(!/^(=[a-fA-F0-9]{2})+$/.test(chain)) {
						return _;
					}

					let chars = chain
						.split("=")
						.map(hex =>
							parseInt(hex,16))
						.filter(Number.isInteger);

					let buf = Buffer.alloc(chars.length);
					let x = 0;
					for(let i in chars) {
						buf.writeUInt8(chars[i], x++);
					}

					return buf.toString();
				})
			}

			value = value.split(";");
			return { meta, value }
		}));
}

if (require.main === module) {
	const fs = require('fs');
	let contents = fs.readFileSync(0, 'utf-8');
	let data = parseVCF(contents, true);

	if(process.argv[2] == "json") {
		console.log(JSON.stringify(data, null, 2));
	} else {
		let csv = contacts.map(contact => {
			let RES = {
				FN: [],	 // Full Name
				ORG: [], // Organisation
				N: [],	 // Names
				TEL: []	 // Tels
			};

			contact.forEach(({ meta, value }) => {
				if(meta.TYPE == "N"  || meta.TYPE == "FN" || meta.TYPE == "ORG") {
					RES[meta.TYPE] = value;
				}

				if(meta.TYPE == "TEL") {
					RES[meta.TYPE].push(value)
				}
			})

			return Object.values(RES).map(x => x.join("\t")).join("\t");

			// Full Name
			// Organisation

			// Family Name
			// Given Name
			// Additional Names
			// Honorific Prefixes
			// Honorific Suffixes

			// Tel1
			// Tel2
			// Tel3
			// ...
		}).join("\n");
		console.log(csv);
	}
} else {
	module.exports = parseVCF;
}