PHP Development Best Practices

PHP is a powerful programming language and many developers have varying skillsets. It is important to follow coding standards when developing with PHP so that other developers can read and understand your code.

Uninitialized variables can cause unexpected results in your program, so it is recommended to initialize them whenever possible. Additionally, unwanted variable declarations cost memory and should be removed when not needed.

1. Compiled Templates

Using a compiled template engine is an important PHP development best practice. It makes the code more readable, supports output escaping and enforces separation of concerns. It is especially helpful when internationalizing a web application. Popular compiled template engines include Twig (used by Symfony) and Zend Framework.

Alternatively, you can use plain PHP templates. This option provides the most flexibility but is slower than using a compiled template engine because it requires more coding.

Another disadvantage is that you must use a debugger to see how the template code works. Additionally, a class template needs to be defined in a header file and included in every source file that uses it. This can lead to bloated source files.

2. Dependency Injection

Dependency injection is a way of loosening coupling between classes by passing objects (dependencies) into a class rather than having it construct them itself. It allows classes to be substituted with other implementations of the same interface, making them more flexible and testable.

Without dependency injection, a class would need to construct its own GroupMembershipService object. But this makes the class dependent on the GroupMembershipService, a tight dependency.

Injection allows classes to be injected with their own dependencies, freeing them up from having to handle the creation of these objects themselves. This is accomplished by using a container that will assemble the required dependencies, either through property or method injection. The containers will also manage the lifetime of the dependency objects, reducing memory use.

3. Database Interaction

When writing a PHP application, the database interaction is an important aspect of the application. It involves transferring data between the front-end software application and the database server. This allows the frontend to deliver relevant information to the end-user in a fast and efficient manner.

When working with databases, it is important to use proper SQL coding practices. This includes ensuring that all strings sent to and from the database are UTF-8 encoded.

Additionally, developers should utilize SQL query optimization tools to improve application performance. Finally, they should use database connection pooling to manage resources efficiently. Lastly, developers should also adhere to the Object Oriented Programming (OOP) paradigm to promote code modularity and maintainability. This can be accomplished by utilizing PHP frameworks like Laravel and Symfony, or by using libraries that facilitate OOP development.

4. Namespaces

Namespaces are a way to provide context (scope) to identifiers in computer programs. They enable modularity and code reusability by grouping logically related functions, variables and classes together into their own namespaces.

For example, if you are writing a library or framework in PHP it is essential to use namespaces so that other developers can easily import your code and that there are no naming conflicts. Similarly, if you are writing an application that will be used by multiple users, it is also important to use namespaces so that other developers do not conflict with your code.

The namespaces that you create can be nested to allow for a hierarchical structure in your codebase. You can also create aliases to make it easier for you to reference the namespaces.

5. Automated Testing

Automated software testing is an important part of continuous integration and continuous delivery development practices. It can speed up the process of testing and help reduce the amount of manual work involved.

Choose an automated testing tool that supports the platform on which your application is running. Ensure that it supports the languages and libraries used in the software you’re testing. Prioritize tools that allow team members to write test scripts at their current technical levels, or provide a way for them to upskill.

Set realistic goals for automated testing and combine it with manual tests. For example, use automated tests for regression and performance testing, while manually executing cross-browser or API tests. Create tests that are user interface (UI) agnostic or resistant to changes, or at the very least avoid creating tests that are dependent on a specific UI.

6. Object Oriented Design

One of the most popular programming paradigms, object oriented design is an important part of PHP development. It promotes code reusability, modularity, and flexibility.

A major feature of OOP is inheritance, which allows classes to inherit properties and methods from other classes. This helps to reduce redundant code and improve coding efficiency.

Inheritance also allows for polymorphism, which allows a class to implement the same method in multiple ways. For example, a shape superclass might have a calculateArea() method. Child classes like Circle and Rectangle can then override the method with their own implementations, enabling customization and simplifying code maintenance.

Another useful OOP technique is function overloading, which occurs when two functions have the same name but serve different purposes. This is an important concept to understand as it can help developers avoid issues like method overriding.

7. Clean Code

Clean code refers to certain guiding principles that developers take into consideration when programming. Its objective is to ensure that the underlying code is easy to read and understand and able to respond to performance demands.

Modularization is a key aspect of clean code. It allows developers to break down complex code into smaller modules, making it easier to manage and test. It also promotes re-usability and encapsulation.

This involves breaking down a function that performs multiple tasks into separate functions with well-defined interfaces. This also helps reduce the likelihood of error-prone cross-dependencies. Another example is using ternary operators instead of an if/else statement, which is faster and more readable. Finally, avoiding unnecessary variable declaration can help minimize memory load. This can be done by using cache or content delivery networks.