Coding standards
The Drupal Coding Standards apply to code within Drupal and its contributed modules.
API documentation and comment standards
How to write documentation that can be parsed by the API module, Drupal project standards for API documentation and comments in PHP code
API Documentation Samples
This page is intended to be a collection of the complete API documentation examples
CSS
CSS coding standards and best practices.
JavaScript
JavaScript coding standards and best practices for Drupal.
Markdown coding standards
This is currently being discussed in [#2191525].
Namespaces
PHP 5.3 introduces namespaces to the language. This page documents how namespaces should be referenced within Drupal and it assumes that
Naming standards for Services and extending Symfony
Elements added to the Request attributes should have a _ prepended unless they come from the path
Object-oriented code
Drupal follows common PHP conventions for object-oriented code, and established industry best practices. As always, though, there are
PHP Exceptions
Basic conventions, exception subclasses, try-catch blocks, inheritance
PSR-4 namespaces and autoloading in Drupal 8
Summary of how Drupal 8 uses the PSR-4 standard for namespace autoloading
SQL coding conventions
Reserved Words, capitalisation and user-supplied data, naming, configuring DB server for standards compliance
Avoid "SELECT * FROM ..."
Using SELECT * FROM {node} queries in versions prior to Drupal 7 can introduce a potential security issue by causing Drupal's Node Access
List of SQL reserved words
The list below represents a combination of the following sources of SQL reserved words:
Temporary placeholders and delimiters
Temporary place-holders and delimiters
Twig coding standards
The majority of Twig coding standards can be found on the Twig website along with Twig documentation. Items on this page (below) are useful
Use Drupal Unicode functions for strings
If you are writing a module or theme, consider that it may be used on web sites around the world, some of which use languages whose
Write E_ALL compliant code
Adjusting the error reporting level
Drupal SimpleTest coding standards
You should follow these conventions when writing a test.
Drupal Markup Style Guide
The Drupal Markup Style Guide is a document in progress on how to:
Configuration file coding standards
Standards related to configuration files in Drupal 8
Composer package naming conventions
This is WIP documentation for [#2401519].
