Configuring Apache to Recognize PHP Code in HTML Files

Typically, Apache web server only executes PHP code in files with the .php extension. However, there are times when you need to execute PHP code in .html files as well. Today, we’ll learn how to configure Apache to recognize PHP code in HTML files.

🎯 When Do You Need This Configuration?

When you need to add PHP functionality to existing HTML files
When you want to hide the .php extension from URLs
When legacy systems require dynamic functionality in HTML files
When you need to maintain URL structure for SEO purposes

📁 Configuration File Location

Apache’s MIME type configuration is managed in the following file:

/etc/apache2/mods-enabled/mime.conf

🔧 Checking Current Configuration

First, let’s check the current configuration file contents:

sudo nano /etc/apache2/mods-enabled/mime.conf

Default configuration content:

#AddHandler cgi-script .cgi

        #
        # For files that include their own HTTP headers:
        #
        #AddHandler send-as-is asis

        #
        # For server-parsed imagemap files:
        #
        #AddHandler imap-file map

        #
        # For type maps (negotiated resources):
        # (This is enabled by default to allow the Apache "It Worked" page
        #  to be distributed in multiple languages.)
        #
        AddHandler type-map var

        #
        # Filters allow you to process content before it is sent to the client.
        #
        # To parse .shtml files for server-side includes (SSI):
        # (You will also need to add "Includes" to the "Options" directive.)
        #
        AddType text/html .shtml
<IfModule mod_include.c>
        AddOutputFilter INCLUDES .shtml
</IfModule>

</IfModule>

✏️ Modifying the Configuration

To make HTML files recognize PHP code, you need to add the following line:

📝 Code to Add

AddType application/x-httpd-php .html

📋 Complete Modified Configuration

#AddHandler cgi-script .cgi

        #
        # For files that include their own HTTP headers:
        #
        #AddHandler send-as-is asis

        #
        # For server-parsed imagemap files:
        #
        #AddHandler imap-file map

        #
        # For type maps (negotiated resources):
        # (This is enabled by default to allow the Apache "It Worked" page
        #  to be distributed in multiple languages.)
        #
        AddHandler type-map var

        #
        # Filters allow you to process content before it is sent to the client.
        #
        # To parse .shtml files for server-side includes (SSI):
        # (You will also need to add "Includes" to the "Options" directive.)
        #
        AddType text/html .shtml
        AddType application/x-httpd-php .html
<IfModule mod_include.c>
        AddOutputFilter INCLUDES .shtml
</IfModule>

</IfModule>

🔄 Restarting the Server

After changing the configuration, you need to reload the Apache server:

sudo service apache2 reload

sudo systemctl reload apache2

🧪 Testing the Configuration

Let’s test if the configuration has been applied correctly:

1. Create a Test File

sudo nano /var/www/html/test.html

2. Write Test Code

<!DOCTYPE html>
<html>
<head>
    <title>PHP in HTML Test</title>
</head>
<body>
    <h1>PHP Code Test</h1>
    <p>Current time: <?php echo date('Y-m-d H:i:s'); ?></p>
    <p>Server info: <?php echo $_SERVER['SERVER_SOFTWARE']; ?></p>
</body>
</html>

3. Check in Browser

Access http://your-domain/test.html in your browser to verify that the PHP code is being executed.

⚠️ Important Considerations

1. Security Considerations

Executing PHP in HTML files can increase security risks
Validation of user-uploaded HTML files is necessary
Proper file permission settings are crucial

2. Performance Impact

All HTML files will go through the PHP parser, which can affect performance
Static HTML files will be processed dynamically, reducing caching efficiency

3. Alternative Methods

If you want to apply this only to specific directories or virtual hosts:

<Directory "/var/www/html/dynamic">
    AddType application/x-httpd-php .html
</Directory>

🔍 Troubleshooting

When PHP Code Doesn’t Execute

Check PHP Module:

sudo a2enmod php8.1  # Adjust according to your PHP version

Check Configuration Syntax:
```
sudo apache2ctl configtest
```

Check Error Logs:

sudo tail -f /var/log/apache2/error.log

🎯 Additional Usage Methods

1. Supporting Multiple Extensions

AddType application/x-httpd-php .html .htm .shtml

2. Conditional Application

<FilesMatch "\.html$">
    SetHandler application/x-httpd-php
</FilesMatch>

📚 Conclusion

Configuring HTML files to execute PHP code is simple, but you must fully consider the impact on security and performance.

Especially in production environments:

Apply only to necessary directories
Implement appropriate security measures
Perform regular security audits

Keep these considerations in mind when configuring your server.

💡 Tip: It’s recommended to thoroughly test in a development environment before applying to production!