URL Shortener

An API for a URL shortener

Specifications

• Accepts a URL to be shortened.
• Generates a short URL for the original URL.
• Accepts a short URL and redirects the caller to the original URL.

Bonus points

• Comes with a CLI that can be used to call your service.

Installation

Clone this repository to your personal device.
Navigate to the containing folder in the command line and run:

go run shortener.go

You will see:

Please type a number then enter
1: Shorten URL
2: Get original URL
3: Exit program

Please follow the CLI instructions

Usage

Decode function

The Decode function accepts a Shortened URL as an argument:

• It validates that URL is currently present in the hash
  • If not it returns an error message
• If the URL is valid, it returns the original URL

Input	Output
"www.tech.test/output"	"www.test-url.com/techtest/this_is_a_very_long_url/it_needs_to_be_much_shorter"
shortURL	Error message ("Short URL does not exist")

Encode function

The Encode function accepts a URL string as an argument and performs several sub functions, which will be extracted in line with Single Responsibility

• It accepts a URL as an argument
• It verifies that it is a valid URL
  • Defined as including either .com or .org as the most commonly used TLDs, but with scope for increasing this library
• It randomly generates a shortened URL
• It needs to verify that the shortened URL does not exist
  • If the URL does exist, 3 needs to occur again
• It saves that shortened URL as a key with the value of the original URL
• It returns that shortened URL as a string

Input	Output
"www.test-url.com/techtest/this_is_a_very_long_url/it_needs_to_be_much_shorter"	"www.tech.test/output"
testshortenthislongurlplease	Error Message ("Not a valid URL")
""	Error Message ("Not a valid URL")

## Current limitations and possible solutions

• The same long URL will receive different short URLs if given twice
  • With the use of key-value map, it is not possible to search through all the existant values to verify if it has already been added
• The database does not persist between sessions
  • the database map is created whenever shortener.go is run, so saved URLs do not persist between sessions

A possible solution to both of the above would be to implement database/SQL package, along with a method for checking the long URL against the database and retrieving and returning the matching short URL, this would function similarly to the loop used in GetUniqueKey.

• The returned URL does not open the window as a webpage

This could be implemented through use of the net/http package