{"id":4425,"date":"2019-12-09T04:53:41","date_gmt":"2019-12-09T04:53:41","guid":{"rendered":"https:\/\/www.hostinger.com\/tutorials\/?p=4425"},"modified":"2026-03-09T19:19:21","modified_gmt":"2026-03-09T19:19:21","slug":"codeigniter-tutorial","status":"publish","type":"post","link":"\/ng\/tutorials\/codeigniter-tutorial","title":{"rendered":"CodeIgniter tutorial: the complete guide"},"content":{"rendered":"

Website development can seem challenging, especially if tackled without any assistance. Luckily, there are development tools like CodeIgniter. It’s a PHP framework maintained by the British Columbia Institute of Technology with a simple yet effective toolkit for developing web applications.<\/p>

In this CodeIgniter tutorial, we’ll go through the process of installing and setting up the CodeIgniter framework on web hosting and a VPS and demonstrate how to create a simple web application.<\/p>

\"\"<\/a><\/figure>

\n\n\n\n\n<\/p>

Set Up CodeIgniter for Your Website<\/h2>

Before we start, keep in mind that CodeIgniter requires a Linux, Apache, MySQL, and PHP (LAMP) stack. Luckily, it comes pre-installed with Hostinger’s web hosting plans<\/a>.<\/p>

However, if you choose a VPS plan<\/a>, you will need to install the LAMP stack first. Here’s how to install LAMP on Ubuntu<\/a> or CentOS<\/a>. When done, proceed with the CodeIgniter setup.<\/p>

\"Hostinger<\/a><\/figure>

Step 1. Installing CodeIgniter<\/h3>

CodeIgniter can be installed automatically via Composer or manually by using File Manager.<\/p>

Important!<\/strong> For the Composer method, SSH access is required. Use PuTTY<\/a> \/ Powershell on Windows or the built-in terminal shell on Linux and macOS. <\/p><\/div>\n\n\n\n<\/p>

Install CodeIgniter 4 Using Composer<\/strong><\/p>

    \n
  1. Log in to your SSH account and navigate to the public_html <\/strong>root directory with this command:<\/li>\n<\/ol>
    cd domains\/yourdomain.com\/public_html<\/pre>
      \n
    1. Install CodeIgniter 4.<\/li>\n<\/ol>
      composer create-<\/strong>project codeigniter4\/<\/strong>appstarter project-<\/strong>root <\/pre>
      The command above will create a project-root<\/strong> directory for the CodeIgniter files. In this tutorial, we’re using the latest stable CodeIgniter version – 4.1.9<\/strong>. You can use the command below from your CodeIgniter directory to update it:<\/p>
      composer update<\/pre>
        \n
      1. For convenience, we recommend moving the contents of project-root<\/strong> to the public_html<\/strong> directory. First, determine the current directory with this command:<\/li>\n<\/ol>
        pwd <\/pre>
        It will look something like this: <\/p>
        \/home\/u123456789\/domains\/yourdomain.com\/public_html <\/pre>
        Now move the files: <\/p>
        mv project-root\/* \/home\/u123456789\/domains\/yourdomain.com\/public_html <\/pre>
          \n
        1. Once that’s done, enter this URL into the browser:<\/li>\n<\/ol>
          https:\/\/yourdomain.com\/public <\/a> <\/pre>
          Make sure to replace yourdomain.com<\/strong> with your domain.<\/p>
          CodeIgniter’s default screen will appear, letting you know it was installed successfully.<\/p>
          Install CodeIgniter 4 Manually<\/strong><\/p>
          If you want to skip the SSH part needed for Composer, go with the manual installation.<\/p>
          Remember that even though the manual method is simple, you will need to check for merge conflicts when updating your website. Follow these steps to perform the manual installation:<\/p>
            \n
          1. Download the latest version of CodeIgniter<\/a>.<\/li>\n\n\n\n
          2. Using File Manager, extract it in the root directory – yourdomain.com\/public_html<\/strong>.<\/li>\n\n\n\n
          3. The framework-4.1.9<\/strong> folder will appear. Open it and double-click the folder within. You should see a window like this one:<\/li>\n<\/ol>
            \"A<\/a><\/figure><\/div>
            Press CTRL + A<\/strong> to select all the files and use the Move<\/strong> button to transfer everything to public_html<\/strong>:<\/p>
            \"All<\/a><\/figure><\/div>
            The path will look like this:<\/p>
            \"The<\/a><\/figure><\/div>
              \n
            1. Open the browser and enter this URL:<\/li>\n<\/ol>
              https:\/\/yourdomain.com\/public<\/code><\/a><\/pre>
              Make sure to replace yourdomain.com<\/strong> with your domain name.<\/p>
              CodeIgniter’s default screen will appear, which means it was installed successfully.<\/p>
              Step 2. Configuring CodeIgniter<\/h3>
              After installing CodeIgniter, it’s crucial to configure it so it works correctly. We recommend starting by creating a .htaccess<\/strong><\/a> file and pasting this snippet into it:<\/p>
              RewriteEngine on\nRewriteCond %{REQUEST_URI} !^public\nRewriteRule ^(.*)$ public\/$1 [L]<\/pre>
              These .htaccess<\/strong> rules will make the CodeIgniter website URL look like this:<\/p>
              https:\/\/yourdomain.com <\/pre>
              Instead of:<\/p>
              https:\/\/yourdomain.com\/public<\/pre>
              After that, proceed with the advanced configuration.<\/p>
              Configuring CodeIgniter for Web Hosting Plans<\/strong><\/p>
              In this section, we’ll discuss the advanced settings for web hosting plans. Let’s start with a new MySQL database.<\/p>
                \n
              1. Find the Hosting<\/strong> → Manage<\/strong> → MySQL Databases<\/strong> section on Hostinger’s hPanel<\/a>:<\/li>\n<\/ol>
                \"The<\/a><\/figure><\/div>
                  \n
                1. Once there, specify the database name, username, and password and click Create<\/strong>:<\/li>\n<\/ol>
                  \"Databases<\/a><\/figure><\/div>
                    \n
                  1. Navigate to File Manager<\/strong> and open the Database.php<\/strong> file for editing. Here’s the full path:<\/li>\n<\/ol>
                    \/domains\/yourdomain.com\/public_html\/app\/Config\/Database.php<\/code><\/pre>
                      \n
                    1. Locate the following section of the file and replace the details with the information of your newly-created database – username<\/strong>, password<\/strong>, and database<\/strong>. The rest of the values should follow this example:<\/li>\n<\/ol>
                      public $default = [\n'DSN'      => '',\n'hostname' => 'localhost',\n'username' => 'u123456789_user',\n'password' => 'Y0ur$tr0ngPa$$w0rd',\n'database' => 'u123456789_name',\n'DBDriver' => 'MySQLi',\n'DBPrefix' => '',\n'pConnect' => false,\n'DBDebug'  => (ENVIRONMENT !== 'production'),\n'charset'  => 'utf8',\n'DBCollat' => 'utf8_general_ci',\n'swapPre'  => '',\n'encrypt'  => false,\n'compress' => false,\n'strictOn' => false,\n'failover' => [],\n'port'     => 3306,\n];<\/pre>
                        \n
                      1. Set up your domain name by modifying CodeIgniter’s App.php<\/strong> file found here:<\/li>\n<\/ol>
                        \/domains\/yourdomain.com\/public_html\/app\/Config\/App.php<\/code><\/pre>
                          \n
                        1. Locate the following line and change its value to your real domain name:<\/li>\n<\/ol>
                          public $baseURL = 'https:\/\/yourdomain.com\/'; <\/code><\/pre>
                          Save the file and exit.<\/p>
                          The database is now synced with CodeIgniter.<\/p>
                          Configuring Virtual Hosts on VPS<\/strong><\/p>
                          VPS users can run multiple CodeIgniter applications on a single domain name. To do so, they need to set up virtual hosts.<\/p>
                          Important!<\/strong> Make sure that your VPS is using Apache and not Nginx or any other web server<\/p><\/div>\n\n\n\n<\/p>
                            \n
                          1. Ensure that the document root is synced with the installation directory of CodeIgniter. To do so, open the virtual host file.<\/li>\n<\/ol>
                            sudo nano \/etc\/apache2\/sites-enabled\/000-default<\/code><\/pre>
                              \n
                            1. Look for the following block:<\/li>\n<\/ol>
                              <VirtualHost *:80>\nDocumentRoot \/path\/to\/codeigniter\n[.......]\n<VirtualHost *:80><br><\/pre>
                                \n
                              1. Change \/path\/to\/codeigniter<\/strong> with the actual path of the CodeIgniter installation directory. By doing this, all URLs will point to this folder. Save the changes by pressing CTRL + X<\/strong> and Y<\/strong>.<\/li>\n<\/ol>
                                For a more efficient development process, get rid of index.php<\/strong> from CodeIgniter’s URL format. Here’s how to do it:<\/p>
                                  \n
                                1. Open the config.php<\/strong> file.<\/li>\n<\/ol>
                                  nano \/public_html\/app\/Config\/App.php<\/pre>
                                  Locate the following line:<\/p>
                                  public $indexPage = 'index.php';<\/pre>
                                  Replace it with this:<\/p>
                                  public $indexPage = '';<\/pre>
                                    \n
                                  1. It’s necessary to re-route future requests by modifying the .htaccess<\/strong> file to ensure that no errors appear. Before doing so, check whether mod_rewrite<\/strong> is enabled.<\/li>\n<\/ol>
                                    apache2ctl -M<\/pre>
                                    The above command will output the capabilities of the server. If mod_rewrite<\/strong> is on the list, continue to the next step. Otherwise, execute this line: <\/p>
                                    a2enmod rewrite<\/pre>
                                    Then, restart Apache.<\/p>
                                    sudo service apache2 restart <\/code><\/pre>
                                      \n
                                    1. Create a .htaccess<\/strong> file in the root folder of CodeIgniter.<\/li>\n<\/ol>
                                      nano public_html\/.htaccess<\/pre>
                                        \n
                                      1. Paste the following lines to the file. If .htaccess<\/strong> was already created during the configuration part of the tutorial, add all the lines except for the first one. Save the changes and exit the file.<\/li>\n<\/ol>
                                        RewriteEngine on\nRewriteCond %{REQUEST_FILENAME} !-f\nRewriteCond %{REQUEST_FILENAME} !-d\nRewriteRule .* index.php?\/$0 [PT,L]<br><\/pre>
                                          \n
                                        1. Let Apache know that it should look for the newly-created .htaccess<\/strong> file. To achieve this, open the virtual host file again:<\/li>\n<\/ol>
                                          sudo nano \/etc\/apache2\/sites-enabled\/000-default<\/pre>
                                          Ensure that AllowOverride<\/strong> is set to All<\/strong>, as shown below:<\/p>
                                          <Directory>\nOptions Indexes FollowSymLinks MultiViews\nAllowOverride All\nOrder allow,deny\nallow from all\n<\/Directory><\/pre>
                                          After confirming it, save the file.<\/p>
                                          If done correctly, index.php<\/strong> won’t appear, making the URL look cleaner.<\/p>
                                          Understanding MVC<\/h2>
                                          Before continuing our CodeIgniter tutorial and learning how to build an application with the framework, we should cover the basics of the model-view-controller (MVC) pattern.<\/p>
                                          Simply put, MVC is a web development architecture paradigm. It states that the business logic<\/a> in any application should be separated from the presentation.<\/p>