Data: .ICS to .CSV converter, vibe-coded

Calendar (.ics) File Structure

BEGIN:VCALENDAR

…

BEGIN:VEVENT

CREATED:20151219T021727Z

DTEND;TZID=America/Toronto:20170515T110000

DTSTAMP:20151219T021727Z

DTSTART;TZID=America/Toronto:20170515T100000

LAST-MODIFIED:20151219T021727Z

RRULE:FREQ=DAILY;UNTIL=20170519T035959Z

SEQUENCE:0

SUMMARY:Meeting

TRANSP:OPAQUE

UID:21B97459-D97B-4B23-AF2A-E2759745C299

END:VEVENT

END:VCALENDAR




Web App

ICS to CSV Converter

📁 Click to select or drag & drop an .ics file

Python

#!/usr/bin/env python3

import re, csv, sys

from pathlib import Path

if len(sys.argv) != 2:

sys.exit("Usage: python3 ics_to_csv.py <filepath.ics>")

input_path = Path(sys.argv[1])

output_path = input_path.with_suffix('.csv')

events = re.findall(r'BEGIN:VEVENT(.*?)END:VEVENT', input_path.read_text(), re.DOTALL)

with open(output_path, 'w', newline='') as f:

writer = csv.DictWriter(f, fieldnames=['Date', 'Summary'])

writer.writeheader()

for event in events:

if (date := re.search(r'DTSTART;VALUE=DATE:(\d{8})', event)) and (summary := re.search(r'SUMMARY:(.*)', event)):

writer.writerow({'Date': f"{date[1][:4]}-{date[1][4:6]}-{date[1][6:]}", 'Summary': summary[1].strip()})

print(f"Converted {len(events)} events\nOutput: {output_path}")

JavaScript

#!/usr/bin/env node

const fs = require('fs');

const path = require('path');

if (process.argv.length !== 3) {

console.error("Usage: node ics_to_csv.js <filepath.ics>");

process.exit(1);

}

const inputPath = process.argv[2];

const outputPath = inputPath.replace(/\.ics$/i, '.csv');

const content = fs.readFileSync(inputPath, 'utf8');

const events = content.match(/BEGIN:VEVENT([\s\S]*?)END:VEVENT/g) || [];

const rows = events.map(event => {

const date = event.match(/DTSTART;VALUE=DATE:(\d{8})/)?.[1];

const summary = event.match(/SUMMARY:(.*)/)?.[1]?.trim();

return date && summary ? `${date.slice(0,4)}-${date.slice(4,6)}-${date.slice(6)},"${summary.replace(/"/g, '""')}"` : null;

}).filter(Boolean);

fs.writeFileSync(outputPath, `Date,Summary\n${rows.join('\n')}`);

console.log(`Converted ${events.length} events\nOutput: ${outputPath}`);

C#

using System.Text.RegularExpressions;

if (args.Length != 1) { Console.Error.WriteLine("Usage: ics_to_csv <filepath.ics>"); return 1; }

var input = args[0];

var output = Path.ChangeExtension(input, ".csv");

var content = File.ReadAllText(input);

var events = Regex.Matches(content, @"BEGIN:VEVENT([\s\S]*?)END:VEVENT");

var rows = events.Select(e => {

var date = Regex.Match(e.Value, @"DTSTART;VALUE=DATE:(\d{8})").Groups[1].Value;

var summary = Regex.Match(e.Value, @"SUMMARY:(.*)").Groups[1].Value.Trim();

return date.Length == 8 && summary.Length > 0 ? $"{date[..4]}-{date[4..6]}-{date[6..]},\"{summary.Replace("\"", "\"\"")}\"" : null;

}).Where(r => r != null);

File.WriteAllText(output, $"Date,Summary\n{string.Join("\n", rows)}");

Console.WriteLine($"Converted {events.Count} events\nOutput: {output}");

return 0;

Go

package main

import (

"fmt"

"os"

"regexp"

"strings"

)

func main() {

if len(os.Args) != 2 {

fmt.Fprintln(os.Stderr, "Usage: go run ics_to_csv.go <filepath.ics>")

os.Exit(1)

}

input := os.Args[1]

output := strings.TrimSuffix(input, ".ics") + ".csv"

content, _ := os.ReadFile(input)

eventRe := regexp.MustCompile(`BEGIN:VEVENT([\s\S]*?)END:VEVENT`)

dateRe := regexp.MustCompile(`DTSTART;VALUE=DATE:(\d{8})`)

summaryRe := regexp.MustCompile(`SUMMARY:(.*)`)

events := eventRe.FindAllString(string(content), -1)

var rows []string

for _, event := range events {

if dateMatch := dateRe.FindStringSubmatch(event); dateMatch != nil {

if summaryMatch := summaryRe.FindStringSubmatch(event); summaryMatch != nil {

date := dateMatch[1]

summary := strings.TrimSpace(summaryMatch[1])

rows = append(rows, fmt.Sprintf("%s-%s-%s,\"%s\"", date[:4], date[4:6], date[6:], strings.ReplaceAll(summary, `"`, `""`)))

}

}

}

os.WriteFile(output, []byte("Date,Summary\n"+strings.Join(rows, "\n")), 0644)

fmt.Printf("Converted %d events\nOutput: %s\n", len(events), output)

}