There are quite a few URL shorteners out there on the Internet; however, there’s always room for a little fun and sometimes people or companies require their own solutions rather than just using an external provider. The project in this tutorial covers just that—developing a URL shortener in CodeIgniter that can be used by anyone.
To make this app, we’ll need to do a few things: we’ll create two controllers, one to create a shortened URL and one to redirect a shortened URL to its actual location on the Web.
We’ll create language files to store text, creating a foundation for multiple language support should you wish to implement it.
We will also make amends to the
config/routes.php file—this is to ensure that the shortened URL is as short as it can be.
In this tutorial, we will cover the following topics:
- Design and wireframes
- Creating the database
- Adjusting the
- Creating the model
- Creating the views
- Creating the controllers
- Putting it all together
So without further ado, let’s get on with it.
Design and wireframes
Before we start building, we should always take a look at what we plan to build.
Firstly, a brief description of our intent: we plan to build an app that will display a simple form to the user. The user will be encouraged to enter a URL into the form and submit that form.
A unique code will be generated and associated with the URL entered by the user. This URL and unique code will be saved to a database.
A new URL will be shown to the user containing the unique code we just generated. That unique code will be appended to the URL of the app we’re building. Should the user (or anyone else) click on that link, the app will look up the unique code in the database. If the unique code exists, it will redirect the user to the original URL associated with that unique code.
So, let’s take a look at some wireframes to help us understand what this might look like on screen:
This is the first page that the user will see. The user is invited to enter a URL into the textbox and hit the Go button.
The page will be submitted and code will be generated. Both this code and the original URL will be saved to the database. The user will then see the new URL we’ve just created for them. They can copy that URL to their clipboard (for pasting into an e-mail and so on) or click on it there and then if they wish. This is shown in the following screenshot:
We’re going to create six files for this application, as follows:
/path/to/codeigniter/application/models/urls_model.php: This file provides access to the database and allows us to create the
url_code, save the record to the database, and also retrieve the original URL from the database.
/path/to/codeigniter/application/views/create/create.php: This file provides us with our interface, the user facing form, and any messages needed to inform the user of their actions or the system’s actions.
/path/to/codeigniter/application/views/nav/top_nav.php: This file provides a navigation bar at the top of the page.
/path/to/codeigniter/application/controllers/create.php: This file performs validation checks on the URL inputted by the user, calls any helpers, and so on.
/path/to/codeigniter/application/controllers/go.php: This file provides support for shortened URLs. It gets the unique code parameter from the URI (first segment), sends it to the
Urls_model,and redirects the user to the associated
url_addressif it exists.
/path/to/codeigniter/application/language/english/en_admin_lang.php: This file provides language support for the application.
The file structure of the preceding six files is as follows:
application/ ├── controllers/ │ ├── create.php │ ├── go.php ├── models/ │ ├── urls_model.php ├── views/create/ │ ├── create.php ├── views/nav/ │ ├── top_nav.php ├── language/english/ ├── en_admin_lang.php