Project URL: https://roadmap.sh/projects/url-shortening-service

A simple, clean RESTful API to create, retrieve, update, delete short URLs and fetch access statistics. Includes an optional redirect endpoint and a minimal frontend at /.

• Java 21, Spring Boot 3 (Web, Data JPA, Validation)
• MySQL (Homebrew)
• Lombok

• Java 21+
• MySQL running locally (Homebrew)
  • Check: brew services list | grep -i mysql

Default datasource values are set in src/main/resources/application.properties:

• spring.datasource.url=jdbc:mysql://localhost:3306/url_shortener?createDatabaseIfNotExist=true...
• spring.datasource.username=root
• spring.datasource.password= (empty)

Override via environment variables (recommended):

• DB_URL, DB_USERNAME, DB_PASSWORD

mvn -DskipTests package

java -jar target/url-shortening-service-1.0-SNAPSHOT.jar

The app listens on http://localhost:8080.

Open http://localhost:8080/ to create and fetch short URLs interactively.

• Create Short URL
  • POST /shorten
  • Body: {"url": "https://www.example.com/long" }
  • 201 Created, returns JSON with id, url, shortCode, createdAt, updatedAt
• Retrieve Original URL (increments access count)
  • GET /shorten/{shortCode}
  • 200 OK
• Update Short URL
  • PUT /shorten/{shortCode}
  • Body: {"url": "https://www.example.com/updated" }
  • 200 OK
• Delete Short URL
  • DELETE /shorten/{shortCode}
  • 204 No Content
• Get Statistics
  • GET /shorten/{shortCode}/stats
  • 200 OK, includes accessCount
• Optional Redirect
  • GET /r/{shortCode} → 302 Found to the original URL (increments access count)

# Create curl -s -X POST http://localhost:8080/shorten \ -H 'Content-Type: application/json' \ -d '{"url":"https://example.com/very/long/path"}'| jq .# Get curl -s http://localhost:8080/shorten/abc123 | jq .# Update curl -s -X PUT http://localhost:8080/shorten/abc123 \ -H 'Content-Type: application/json' \ -d '{"url":"https://example.com/updated"}'| jq .# Stats curl -s http://localhost:8080/shorten/abc123/stats | jq .# Delete curl -i -X DELETE http://localhost:8080/shorten/abc123 # Redirect curl -i http://localhost:8080/r/abc123

• Short codes are generated randomly, length 6+, collision-checked, and lengthened on repeated collisions.
• accessCount is incremented on GET /shorten/{shortCode} and /r/{shortCode}; not on stats retrieval.
• Schema is auto-managed (spring.jpa.hibernate.ddl-auto=update).