Good quality PHP code is consistently formatted and contains minimal misuse of the language, violations of pre-set code standards, or bugs. Clean code is high-quality, meaning that it’s reusable, maintainable, easy to test, consistent, and reliable.

PHP code could be considered unreadable or unmaintained if it contains confusing errors such as poor formatting, inconsistent indentation, and one-letter variables. Using too many dependencies could also lead to poor-quality code, as it adds complexity and potentially exposes you to function and security issues. These formatting and dependency issues can lead to confusion when collaborating with other developers, and they can cause errors that are difficult to pinpoint and fix.

PHP code security focuses on ensuring that your own code has minimal vulnerabilities. Often enough, security and quality go hand-in-hand. This is because the less complex (and therefore, higher quality) your code is, the easier it will be to defend against potential attacks. But even though they can be improved in tandem, code security and quality are still two different things.

To reduce PHP code risks, it’s important to focus on securing HTTP session management, filesystem access, and SQL database queries. Proper PHP code security also means looking at the system from the user’s perspective. Ensure that any user-submitted data gets vetted for possible threats and keep error messages as vague and language-neutral as possible. This prevents malicious users from revealing the inner workings of your system or using submission fields to manipulate your data.

When it comes to using open source PHP code, specifically, your team should be vetting all components taken from open source communities. It’s unfortunate, but not everything available for public use is secure by default. So, it’s a good idea to use scanners like Snyk Open Source to ensure that the components and dependencies of components within your application have minimal risk.

Snyk PHP Code Checker is an AI-powered static application security testing (SAST) tool that analyzes PHP code for security issues and common bugs, offering actionable remediation directly in your IDE.