Why Code Sniffers Are Essential for Optimizing Web Development

Editor’s note: This article is part of our Code Optimization series, where we explore how to optimize code for better efficiency, helping you become a more effective coder.

Code optimization is similar to the editing phase of writing. Initially, you may focus on getting your ideas into code, but optimizing that code with tools like code sniffers is crucial to delivering the best possible product.

Code sniffing refers to checking code for compliance with industry standards and best practices. These standards may dictate aspects such as indentation, the placement of curly braces, or variable naming conventions. While not mandatory for building a web application, adhering to these standards is important for internal consistency and ease of code maintenance.

This is why code sniffing is invaluable for all developers, whether working on the frontend or backend. In this article, we’ll explore the process of code sniffing and introduce some utilities that can help you analyze and enforce code standards.

Understanding Code Sniffing

Code sniffing is typically an automated process designed to save time and minimize errors. These tools check source code for compliance with standards established by internal development teams or regulatory bodies.

Code sniffing is similar to code linting but is more detailed. While linting primarily focuses on identifying bugs and syntax errors, sniffing examines how the code is written. For example, a PHP file may function correctly but fail a code sniffing test if variable names don’t adhere to standards (e.g., $myVariable vs $my_variable).

A related concept is code smell, which identifies design flaws in code that may lead to more significant issues. While it overlaps with code standards, it also involves higher-level design principles for writing consistent and maintainable code.

All of these concepts are relevant to code sniffing. However, it’s important to note that sniffing code won’t necessarily identify runtime bugs because its primary focus is on ensuring strict compliance with coding standards.

You might be wondering, do standards even matter? The answer is yes, particularly for optimization and project clean-up. Many developers agree that coding standards are essential in programming and web development, especially on large team projects.

Developer Paul Jones explains the importance of code standards:

“The point of a coding style standard is not to say one style is objectively better than another… Instead, the point is to set up known expectations on how code is going to look.”

If you’re developing a small web app for personal use, it might not seem necessary to follow standards like WCAG 2.0 or PSR-2. However, consider the hundreds of developers working on Adobe Photoshop’s source code. It would be chaotic if each person wrote code in their own style and then tried to merge it all together.

While teams heavily rely on standards, these rules can also benefit individual developers. Code standards exist for everything from CSS to WordPress, so there’s no reason not to try them out and see how they can improve your code quality.

The Importance of Code Standards

Adhering to code standards naturally keeps your code clean and organized. Developers can easily write, read, and follow each other’s work, making collaboration smoother.

Code standards also benefit open-source development by providing clear guidelines for others to follow. Files can be revisited by anyone months or even years later, and they will still be easy to understand.

Maintaining a strict coding style is advisable, even if you create your own. While it requires effort, this type of documentation becomes invaluable as projects grow in size and complexity.

Here are some coding standards to consider across various web languages:

• PEAR Coding Standards (PHP)
• Google Standards for HTML/CSS
• Google Standards for JavaScript
• Django Coding Style (Python)
• Rails Style Guide (Ruby)
• WCAG 2.0 (UX)

Top Resources for Code Sniffing

Today, you can find free code sniffers for almost everything, from HTML/CSS to backend languages like PHP and SQL. While you may not need to use these sniffers or follow standards for every language, it’s worth exploring the options to see what might enhance your code quality and performance.

Frontend Code Sniffers

Although HTML doesn’t require a code sniffer, that didn’t stop Squiz from developing one. It’s completely open-source and hosted on GitHub, allowing you to copy/paste code into the browser or save a bookmarklet to run on individual web pages.

This sniffer checks against WCAG’s three levels of A, AA, and AAA accessibility standards, along with the Section 508 guidelines, which primarily apply to government websites.

CSS developers might find this free CSS code sniffer useful, which is also open-source and hosted through the Node Package Manager.

jQuery users should explore JSCodeSniffer by Dmitry Sheiko. This is another free web app hosted on GitHub that complies with jQuery’s code style guide.

Alternatively, you might want to try linting your JS code with JavaScript Lint or JS Lint. These tools check for syntax errors rather than code standards, but they are also highly beneficial for frontend code optimization.

For reference, it’s also possible to check JS/CSS standards directly with PHP_CodeSniffer.

The PHP Code Sniffer

PHP_CodeSniffer is an essential tool if you’re aiming to comply with PHP coding standards. The package includes several PHP scripts that analyze PHP, JS, and CSS code for compliance with your chosen code style guidelines.

The creator of PHP_CodeSniffer, Greg Sherwood, shared a great backstory about how the idea came to life and the issues it addresses (a recommended read if you have the time).

In summary, Greg’s team was learning JavaScript integrated into a PHP app, aiming to structure the JS code to follow PHP standards for easier switching between languages. This led to the creation of PHP_CodeSniffer.

This is especially useful for PHP developers since the language is relatively lenient with mandatory style requirements. While frameworks like Laravel enforce stricter guidelines, developers should still establish their own coding standards rather than relying solely on third-party frameworks.

Popular standards like PSR-0, PSR-1, and PSR-2 are all widely used and are included with the PHP sniffing library.

However, you can find many other pre-configured code standards for PHP CMS platforms like WordPress, Magento, and Drupal. Drupal core developers even released an official code sniffer module called Coder.

PHP is undoubtedly one of the easiest languages to optimize with code sniffers. If you’re looking for a comprehensive list of PHP code standards, check out this GitHub repository.

Other Backend Code Sniffers

Backend developers work with various languages beyond PHP, and the number of these languages is growing each year. Along with these alternative languages come different code sniffing libraries, such as code-sniffer for Python.

You can find other scripts online or use tools like PyLint. However, integrating this methodology into your development flow requires patience.

Ruby developers also have a range of choices for code linting and analysis. The best options are often free and open-source, such as Ruby Lint, a static code analyzer for modern Ruby code.

While I haven’t found a dedicated Node.js code sniffer yet, I’m hopeful that a project will emerge in the future. There are JS code sniffers that support Node standards, but it’s still a relatively new backend language that needs time to mature.

Lastly, we have SQL syntax used in databases. This code can be trickier to standardize since it’s challenging to find well-supported syntax standards for SQL. However, I did find a SQL formatting web app that should prove immensely helpful when optimizing database queries.

Conclusion

The best way to start code sniffing is by focusing on one language and one standard. HTML/CSS is a great starting point for frontend developers, while PHP is a popular choice among backend developers, especially those working with WordPress.

If you want to learn more, check out these related posts on code sniffing, linting, and automated code analysis for optimization.

• Why You Need Coding Standards
• Code Smells by Jeff Atwood
• PHP Code Sniffer: Installation & Configuration
• Introduction to CodeSniffer (Part 1)
• GitHub Showcase: Clean Code Linters