Understanding Nginx Location Blocks: Differences, Use Cases, and Examples

In this post, we will discuss the differences between various types of location blocks, when to use them, and provide examples to illustrate their use.

Exact match:

The exact match location block is denoted by the “=” modifier. It is used to define an exact match between the requested URL and the location block. Nginx will only process this block if the URL matches the specified path exactly.

Example:

location = /login {
    proxy_pass http://backend/login;
}

In this example, Nginx will route requests for “/login” to the specified backend server. Requests for “/login/other” or “/login-example” will not be processed by this location block

Prefix match:

The prefix match location block is the most commonly used type and has no modifier. It matches the beginning of the requested URL and is ideal for routing requests based on URL structure.

Example:

location /api/ {
    proxy_pass http://backend-api/;
}

In this example, all requests with URLs starting with “/api/” will be routed to the specified backend server. This includes requests for “/api/users”, “/api/posts”, and so on.

Regular expression match:

Regular expression (regex) match location blocks use the “" or "*” modifiers for case-sensitive and case-insensitive matches, respectively. These blocks provide more flexibility when matching URLs, as they can match complex patterns.

Example:

location ~* \.(jpg|jpeg|png|gif)$ {
    root /var/www/images;
}

In this example, Nginx will serve image files with the specified extensions from the “/var/www/images” directory. The case-insensitive match ensures that both uppercase and lowercase extensions will be served.

Non-matching regular expression:

The non-matching regular expression location block uses the “!" or "!*” modifiers for case-sensitive and case-insensitive matches, respectively. This block is useful for excluding specific patterns from being processed by other location blocks.

Example:

location !~* \.(php|cgi)$ {
    deny all;
}

In this example, Nginx will deny requests for files with “.php” and “.cgi” extensions, regardless of case.

When to use what:

• Use exact match location blocks for specific paths that need unique handling.
• Use prefix match location blocks for routing requests based on URL structure or serving static files from specific directories.
• Use regular expression match location blocks for complex URL patterns or when you need case-sensitive or case-insensitive matching.
• Use non-matching regular expression location blocks to exclude specific URL patterns from being processed.

Conclusion:

Nginx location blocks provide powerful and flexible URL routing capabilities for your web server configuration. Understanding the differences between the various types of location blocks and their use cases is essential to ensure optimal performance and functionality. Utilize the appropriate location block based on your requirements to create an efficient and maintainable Nginx configuration.