URL Shortener

A URL Shortener.

3rd Part Library Usage

• Web Engineering
  • Use gin for web framework.
  • Use cors for cross-domain requests. It will let you make requests from any domain.
• Config file
  • Use viper to parse the config file, to make the codes more flexible.
• Database
  • Use sqlite3 for database.
• Cache Storage
  • Use Redis as cache storage.
  • If the Short ID does not exist in the DB, it will add a miss to the Redis.
  • If the Short ID exists in the DB, it will add as hit to the Redis.
  • Limit IP Address.

For the full list, please check on go.mod.

Features

• Init
  • Check if the table or file exists. If not, create it.
  • Loading .env file.
• Add Short Link
  • HTTP POST with JSON body.
  • Check if the input (url, expireAt) is valid.
    • url: require a valid URL. Use url.ParseRequestURI to check.
    • expireAt: require a valid date. Use tools.ConvertTimetoUnix to check. (btw, It will be converted to unix timestamp.)
• Redirect
  • HTTP GET with URL query.
  • It will query the database to get the origin URL. (btw, It will also add a hit to the Redis.)

Function List

func AddURL(c *gin.Context)               // Request for a Short Link
func RedirectURL(c *gin.Context)          // Redirect to the origin link

func CreateTable()                        // Init Table (If a table or file is not found, it will create one.)
func AddData(ShortID string, Link string, ExpireAt int64) // Prepend to DB
func QueryData(ID string) (bool, string)  // Query the Origin Link
func ErrCheck(err error)                  // Check Error

func RandomString(length int) string      // Generate a 5 char string
func CheckLinkValid(Link string) bool     // Check if Link valid
func ConvertTimetoUnix(date string) (bool, int64) // Convert the time format from RFC 3339 UTC to Unix
func CheckIPAddress(ip string) bool       // Check if IP Address valid

Install

• Download the libraries
  go mod download

• Test the server
  go run main.go

• Build
  go build -o url_shortener

Usage

Download the release version from here.

Upload URL API:

1. "url" require a valid URL. (Eg: https://google.com/)
2. "expireAt" require RFC 3399 UTC format.

curl -X POST -H "Content-Type:application/json" http://localhost/api/v1/urls -d '{
    "url": "https://steveyi.net/",
    "expireAt": "2021-02-08T09:20:41Z"
}'

Response:

1. "id" will generate a 5 character random string.
2. "shortUrl" will generate a short URL

{
    "id": "<url_id>",
    "shortUrl": "http://localhost/<url_id>"
}

Redirect URL API:

curl -L -X GET http://localhost/<url_id> => REDIRECT to original URL # HTTP 301

Run with the docker?

• Download the docker image
  docker pull steveyiyo/url-shortener:latest

• Run the docker image
  sudo docker run -p 0.0.0.0:7600:7600 steveyiyo/url-shortener

docker-compose

• docker-compose up -d