This is a Sample URL Shortener made for learning purposes, it uses GoLang, Gin Gonic web framework and requires a redis server.

I used a docker redis container for development, which is one of many possibilities. It has the advantage to be quick to setup:

docker run --name url_short_db -d -p 6379:6379 redis redis-server --appendonly yes

If you are not comfortable with docker I invite you to check redis website for more information on how to set up one.

Each URL is given a unique id (base 10) when created which is in turn converted to another base depending on the character set available. It contains [a-zA-Z0-9] by default so the ids are converted to base 62.

When a url is requested (baseUrl/shortUrlCode) the shortUrlCode is translated back to the URL id and the full URL is retrieved.

The response is then made a redirect to that URL.

[GIN-debug] GET    /:code                    --> github.com/thomas-barthelemy/go-url-shortener/modules/urlShortener.getUrlEndpoint (1 handlers)
[GIN-debug] POST   /api/urls                 --> github.com/thomas-barthelemy/go-url-shortener/modules/urlShortener.postUrlEndpoint (1 handlers)

The POST /api/urls requires a form encoded parameter url.

Things that could be added are legion, here are a few improvements:

• Improving how the id is generated/stored in redis, there is a risk of overriding an existing URL
• Using redis key expiration for the URLs
• Adding the CHAR MAP as a config instead of being hardcoded
• More error handling, mostly ignored so far

In that sense, feel free to PR!