Description

A very straightforward and simple Spring Boot REST application:

• shortens long URLs, persists them in a form of hashed IDs
• original URL is returned by requesting http://localhost:8080/ID
• pre-compiled as a native executable using GraalVM Native image
• written in Kotlin

App launch time comparison (Win 11, 6core CPU, 16GB RAM)

• ./target/urlshortener.exe - Started UrlShortenerApplicationKt in 0.251 seconds (process running for 0.256)
• mvn spring-boot:run - Started UrlShortenerApplicationKt in 2.323 seconds (process running for 2.626)

Room for enhancements

• As we are dealing more with Redis server integration with Spring Boot app inside a GraalVM Native image, we primarily focus on data layer testing (Spring data repository) than API one (Spring REST Controller). The API tests can be added later.
• Logging, custom exceptions

URL shortener showcase

Please make sure Docker is running, this is required for:

• TestContainers (tests inside a native image)
• or manual tests execution (starting a Redis server container).

Before proceeding further, build a GraalVM Native image:

mvn native:compile -Pnative -DskipTests

The compiled executable is available at target/urlshortener

Tests inside a native image:

Run them by executing:

mvn test -Pnative

Manual tests:

Start Redis server:

docker-compose -f docker-compose.yml up -d

Run the pre-compiled executable:

./target/urlshortener

Send a POST request to obtain a short URL id:

curl -X POST -H "Content-Type: application/json" -d "https://google.com/" localhost:8080/shorten

Example output:

curl -X POST -H "Content-Type: application/json" -d "https://google.com/" localhost:8080/shorten
...
< HTTP/1.1 200
...
http://localhost/bf8e423d
...

Get original URL by sending a GET request with shortened URL id:

curl -v http://localhost:8080/bf8e423d

Example output:

curl -v http://localhost:8080/bf8e423d
...
< Location: https://google.com/
...

Stop and remove the Redis server container:

 docker-compose -f docker-compose.yml down