PHP Coding Standards

Dark Brotherhood Coding Standards
Coding Standards and Practices
ASP Coding Standards	CSS Coding Standards	Database Standards
HTML Coding Standards	JavaScript Coding Standards	PHP Coding Standards

General

• All associative arrays should use single quotes around element names.
• All global variables should be referred to using the $GLOBALS['VAR_NAME'] syntax.
• Super global variables should be used as opposed to relying on register_globals being on
• A given include should not be done repeatedly in the same script.

• A closing PHP tag (?>) at the end of the file is extraneous and should be removed to prevent unexpected whitespace output. See: Zend File Formatting Standards
• Hard coded paths should be avoided whenever possible.
• Function and method names should be all lowercase, with underscores separating words: my_function() rather than myFunction().
• Any operation that is being done repeatedly in the application should be functionalized. Functions or Object-Oriented PHP should be used whenever possible.

• Passwords that appear in PHP code must be base64 encoded, then decoded when utilized.
• API classes should be written in preference to functions in the global scope.
• When possible, write code in distinct, testable chunks. (See Unit Testing below.)

Global Variables

• Global variables should be all uppercase and use $GLOBALS where appropriate. Ex. $GLOBALS['MY_GLOBAL_VAR']

• Local variables should NEVER be in all uppercase.

The following global variables should be defined for every script:

Variable	Purpose	Example
$GLOBALS['BASE_DIR']	This is the base directory for the application and should not be hard coded if possible. Used by PSUSmarty and PSUTemplate to create a unique template cache directory.	/var/htdocs/myapp/subdir dirname(__FILE__)
$GLOBALS['BASE_URL']	This is the base URL for the application and should be a full relative path.	/webapp/subdir/
$GLOBALS['TEMPLATES']	Full path to your application's templates directory. Required if using DJBTemplate.	$GLOBALS['BASE_DIR'] . '/templates';
$GLOBALS['TITLE']	Application title, as displayed in templates by DJBTemplate. Required if using DJBTemplate.	"APE"

Templating

• All files that include XHTML and conditional PHP must be separated into a .html and a .tpl file using Smarty. Conditional PHP and HTML code should never exist in the same file.
  • Exception: high traffic content may follow other rendering guidelines due to performance.

Database Abstraction

• Database abstraction with ADOdb should be used when connecting to databases.
• Database connections should be opened using the registry, i.e. tools::db('djb').
• Registry database shortcuts should be defined centrally in the tools class.