Shorten any URL in one click. See exactly where every click came from.

golinkgone.com  ·  Redirects served at tryglg.ink

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What is GoLinkGone?

GoLinkGone turns any long URL into a clean short link under tryglg.ink — with a built-in QR code and a full analytics dashboard. No setup required to shorten a link. Sign up to track every click by country, city, device, and visitor uniqueness.

→ Try it at golinkgone.com

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Features

For anyone

• One-click shortening — paste a URL, hit Generate, get a short link and a print-ready QR code instantly
• Downloadable QR codes — every link ships with a 200×200 PNG, ready for print or sharing offline
• Sub-second redirects — backed by an in-memory key store so every click lands instantly, no database round-trip

For signed-in users

• Per-link analytics dashboard with four views:
  • 24-hour hourly breakdown
  • 7-day and 30-day daily timelines
  • All-time monthly chart
• Three visitor metrics per time bucket — Total Clicks, New Visitors, and Unique Visitors (deduped by hashed IP + User-Agent)
• Top 50 countries and top 15 cities ranked by clicks
• Device breakdown — Phone, Tablet, Desktop, Unknown — shown as a donut chart with percentages
• Timezone-aware charts — all buckets align to the browser's local timezone, including half-hour offsets
• My Links — paginated table to manage, copy, and delete all your short links
• Full account deletion — removes your auth account and cascades through every link and analytics row

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How It Works

Browser  →  Cloudflare edge  →  Caddy (TLS)  →  Spring Boot JVM  →  Supabase Postgres

• Frontend — React + Vite, hosted on Cloudflare Pages at golinkgone.com
• Backend API — Spring Boot on a DigitalOcean droplet, reachable at api.golinkgone.com
• Redirects — same backend, separate Cloudflare zone at tryglg.ink
• Auth + Database — Supabase (Postgres + ES256 JWT)
• Geo-IP — MaxMind GeoLite2, memory-mapped, refreshed weekly

The JVM is never exposed to the public internet directly — only Caddy listens on 80/443, and the droplet firewall allows inbound traffic only from Cloudflare's IP ranges.

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Tech Stack

Layer	Technology
Language	Java 21
Framework	Spring Boot 4.0.3
Security	Spring Security · OAuth2 Resource Server (ES256 JWT)
Database	Supabase Postgres — Spring Data JPA + JdbcTemplate
Connection pool	HikariCP
Caching	Caffeine (URL cache · ownership cache · dashboard caches)
Rate limiting	Bucket4j — token bucket, per IP
Geo-IP	MaxMind GeoLite2-City (memory-mapped · weekly auto-update)
QR codes	ZXing
Primary keys	UUID v7 (time-ordered) via uuid-creator
Async / threads	Java 21 virtual threads
Frontend	React 18 · Vite · Tailwind CSS · Recharts
Frontend hosting	Cloudflare Pages
Backend hosting	DigitalOcean droplet · Docker · Caddy
CI/CD	GitHub Actions → GitHub Container Registry

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Architecture Highlights

Zero-latency redirects

All short keys are loaded into a ConcurrentHashMap at startup — collision checks and existence lookups are O(1) with no database access. Resolved URLs are cached in Caffeine for 24 hours. A typical redirect touches no database at all.

Async click ingestion

The redirect handler enqueues a ClickEventDTO into a bounded in-memory queue and returns the 302 immediately. A background consumer drains the queue in batches every 3 seconds and writes five upserts in a single transaction:

unique_visitors_global  →  lifetime deduplication per (link, visitor)
link_stats_global       →  lifetime totals
link_stats_monthly      →  monthly rollup
link_device_stats       →  device rollup
link_location_stats     →  country / city rollup
unique_visitors_log     →  35-day rolling raw log for time-window queries

New-visitor attribution uses INSERT ... ON CONFLICT DO NOTHING return codes — 1 = new, 0 = returning — without a separate SELECT.

Privacy-preserving visitor identity

Raw IPs are never stored. Visitor identity is murmur3_128(ip + "|" + userAgent) → UUID, used solely for deduplication counting.

Dashboard query model

getDashboard runs two independent queries in parallel: getLinkSummary (4 sequential reads — lifetime totals, top countries, top cities, device breakdown) and getTimeline (1 read). Both results are cached for 1 minute. Cold load: 2 simultaneous DB connections. Warm: 0.

Dual-domain isolation

A servlet filter enforces routing by Host header before Spring Security processes the request:

• tryglg.ink — only GET /{key} and HEAD /{key} reach the handler; all other paths return 404
• api.golinkgone.com — all API paths pass through; short-key paths return 404

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API Reference

Method	Path	Auth	Description
GET	/health	Public	Health check
GET	/actuator/health	Public	Detailed health (includes GeoIP status)
POST	/create	Public	Shorten a URL → { shortUrl, qrCode }
GET / HEAD	/{shortKey}	Public	Redirect + async analytics
GET	/my-links	JWT	Paginated list of user's links
GET	/{shortKey}/dashboard	JWT (owner)	Per-link analytics
DELETE	/{shortKey}	JWT (owner)	Delete link and all analytics
DELETE	/account	JWT	Delete account and cascade all data

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Local Development

Prerequisites

• Java 21, Maven
• A Supabase project (database + auth)
• A MaxMind GeoLite2 license key (free at maxmind.com)

Environment

Create a .env file at the project root:

DB_URL=jdbc:postgresql://<host>:5432/postgres
DB_USERNAME=postgres
DB_PASSWORD=...
ISSUER_URI=https://<project>.supabase.co/auth/v1
JWK_SET_URI=https://<project>.supabase.co/auth/v1/.well-known/jwks.json
PROJECT_URL=https://<project>.supabase.co
SUPABASE_SERVICE_ROLE_KEY=...
MAXMIND_LICENSE_KEY=...

Run

./mvnw spring-boot:run

Starts at http://localhost:8080. Point the frontend's VITE_API_BASE_URL here.

Test

./mvnw test

Integration tests use Testcontainers and require Docker.

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Deployment

Service	Platform
Backend	DigitalOcean droplet — Docker + Caddy (TLS via Cloudflare Origin Certs)
Frontend	Cloudflare Pages at golinkgone.com
Auth + DB	Supabase

On every push to main, GitHub Actions builds the fat JAR, publishes the Docker image to GHCR, and SSHs into the droplet to pull and restart the container.

Required GitHub secrets: GHCR_USER · GHCR_PAT · DROPLET_HOST · DROPLET_USER · DROPLET_SSH_KEY

Required env vars on the droplet (glg.env):

DB_URL                    # Supabase session pooler JDBC URL (IPv4)
DB_USERNAME / DB_PASSWORD
ISSUER_URI / JWK_SET_URI
PROJECT_URL
SUPABASE_SERVICE_ROLE_KEY
MAXMIND_LICENSE_KEY

Cloudflare SSL/TLS mode must be set to Full (strict). The droplet firewall should allow ports 80/443 only from Cloudflare's published IP ranges.

The GeoLite2 database (GeoLite2-City.mmdb) must be present at /opt/glg/GeoLite2-City.mmdb before first start. The app refreshes it automatically every Sunday at 03:00 UTC.

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License

MIT