Coding Standards

CakePHP developers will use the PSR-2 coding style guide in addition to the following rules as coding standards.

It is recommended that others developing CakeIngredients follow the same standards.

You can use the CakePHP Code Sniffer to check that your code follows required standards.

Adding New Features

No new features should be added, without having their own tests – which should be passed before committing them to the repository.

IDE Setup

Please make sure your IDE is set up to “trim right” on whitespaces. There should be no trailing spaces per line.

Most modern IDEs also support an .editorconfig file. The CakePHP app skeleton ships with it by default. It already contains best practise defaults.


Four spaces will be used for indentation.

So, indentation should look like this:

// base level
    // level 1
        // level 2
    // level 1
// base level


$booleanVariable = true;
$stringVariable = 'moose';
if ($booleanVariable) {
    echo 'Boolean value is true';
    if ($stringVariable === 'moose') {
        echo 'We have encountered a moose';

In cases where you’re using a multi-line function call use the following guidelines:

  • Opening parenthesis of a multi-line function call must be the last content on the line.
  • Only one argument is allowed per line in a multi-line function call.
  • Closing parenthesis of a multi-line function call must be on a line by itself.

As an example, instead of using the following formatting:

$matches = array_intersect_key($this->_listeners,
                    array_keys($this->_listeners), 0)));

Use this instead:

$matches = array_intersect_key(
        preg_grep($matchPattern, array_keys($this->_listeners), 0)

Line Length

It is recommended to keep lines at approximately 100 characters long for better code readability. Lines must not be longer than 120 characters.

In short:

  • 100 characters is the soft limit.
  • 120 characters is the hard limit.

Control Structures

Control structures are for example “if”, “for”, “foreach”, “while”, “switch” etc. Below, an example with “if”:

if ((expr_1) || (expr_2)) {
    // action_1;
} elseif (!(expr_3) && (expr_4)) {
    // action_2;
} else {
    // default_action;
  • In the control structures there should be 1 (one) space before the first parenthesis and 1 (one) space between the last parenthesis and the opening bracket.
  • Always use curly brackets in control structures, even if they are not needed. They increase the readability of the code, and they give you fewer logical errors.
  • Opening curly brackets should be placed on the same line as the control structure. Closing curly brackets should be placed on new lines, and they should have same indentation level as the control structure. The statement included in curly brackets should begin on a new line, and code contained within it should gain a new level of indentation.
  • Inline assignments should not be used inside of the control structures.
// wrong = no brackets, badly placed statement
if (expr) statement;

// wrong = no brackets
if (expr)

// good
if (expr) {

// wrong = inline assignment
if ($variable = Class::function()) {

// good
$variable = Class::function();
if ($variable) {

Ternary Operator

Ternary operators are permissible when the entire ternary operation fits on one line. Longer ternaries should be split into if else statements. Ternary operators should not ever be nested. Optionally parentheses can be used around the condition check of the ternary for clarity:

// Good, simple and readable
$variable = isset($options['variable']) ? $options['variable'] : true;

// Nested ternaries are bad
$variable = isset($options['variable']) ? isset($options['othervar']) ? true : false : false;

Template Files

In template files (.ctp files) developers should use keyword control structures. Keyword control structures are easier to read in complex template files. Control structures can either be contained in a larger PHP block, or in separate PHP tags:

if ($isAdmin):
    echo '<p>You are the admin user.</p>';
<p>The following is also acceptable:</p>
<?php if ($isAdmin): ?>
    <p>You are the admin user.</p>
<?php endif; ?>


Always try to be as strict as possible. If a non-strict test is deliberate it might be wise to comment it as such to avoid confusing it for a mistake.

For testing if a variable is null, it is recommended to use a strict check:

if ($value === null) {
    // ...

The value to check against should be placed on the right side:

// not recommended
if (null === $this->foo()) {
    // ...

// recommended
if ($this->foo() === null) {
    // ...

Function Calls

Functions should be called without space between function’s name and starting parenthesis. There should be one space between every parameter of a function call:

$var = foo($bar, $bar2, $bar3);

As you can see above there should be one space on both sides of equals sign (=).

Method Definition

Example of a method definition:

public function someFunction($arg1, $arg2 = '')
    if (expr) {
    return $var;

Parameters with a default value, should be placed last in function definition. Try to make your functions return something, at least true or false, so it can be determined whether the function call was successful:

public function connection($dns, $persistent = false)
    if (is_array($dns)) {
        $dnsInfo = $dns;
    } else {
        $dnsInfo = BD::parseDNS($dns);

    if (!($dnsInfo) || !($dnsInfo['phpType'])) {
        return $this->addError();
    return true;

There are spaces on both side of the equals sign.


Arguments that expect objects, arrays or callbacks (callable) can be typehinted. We only typehint public methods, though, as typehinting is not cost-free:

 * Some method description.
 * @param \Cake\ORM\Table $table The table class to use.
 * @param array $array Some array value.
 * @param callable $callback Some callback.
 * @param boolean $boolean Some boolean value.
public function foo(Table $table, array $array, callable $callback, $boolean)

Here $table must be an instance of \Cake\ORM\Table, $array must be an array and $callback must be of type callable (a valid callback).

Note that if you want to allow $array to be also an instance of \ArrayObject you should not typehint as array accepts only the primitive type:

 * Some method description.
 * @param array|\ArrayObject $array Some array value.
public function foo($array)

Anonymous Functions (Closures)

Defining anonymous functions follows the PSR-2 coding style guide, where they are declared with a space after the function keyword, and a space before and after the use keyword:

$closure = function ($arg1, $arg2) use ($var1, $var2) {
    // code

Method Chaining

Method chaining should have multiple methods spread across separate lines, and indented with four spaces:

    ->subject('A great message')

Commenting Code

All comments should be written in English, and should in a clear way describe the commented block of code.

Comments can include the following phpDocumentor tags:

PhpDoc tags are very much like JavaDoc tags in Java. Tags are only processed if they are the first thing in a DocBlock line, for example:

 * Tag example.
 * @author this tag is parsed, but this @version is ignored
 * @version 1.0 this tag is also parsed
 * Example of inline phpDoc tags.
 * This function works hard with foo() to rule the world.
 * @return void
function bar()

 * Foo function.
 * @return void
function foo()

Comment blocks, with the exception of the first block in a file, should always be preceded by a newline.

Variable Types

Variable types for use in DocBlocks:

A variable with undefined (or multiple) type.
Integer type variable (whole number).
Float type (point number).
Logical type (true or false).
String type (any value in ” ” or ‘ ‘).
Null type. Usually used in conjunction with another type.
Array type.
Object type. A specific class name should be used if possible.
Resource type (returned by for example mysql_connect()). Remember that when you specify the type as mixed, you should indicate whether it is unknown, or what the possible types are.
Callable function.

You can also combine types using the pipe char:


For more than two types it is usually best to just use mixed.

When returning the object itself, e.g. for chaining, one should use $this instead:

 * Foo function.
 * @return $this
public function foo()
    return $this;

Including Files

include, require, include_once and require_once do not have parentheses:

// wrong = parentheses
require_once ($class);

// good = no parentheses
require_once 'ClassFileName.php';
require_once $class;

When including files with classes or libraries, use only and always the require_once function.

PHP Tags

Always use long tags (<?php ?>) instead of short tags (<? ?>). The short echo should be used in template files (.ctp) where appropriate.

Short Echo

The short echo should be used in template files in place of <?php echo. It should be immediately followed by a single space, the variable or function value to echo, a single space, and the php closing tag:

// wrong = semicolon, no spaces

// good = spaces, no semicolon
<td><?= $name ?></td>

As of PHP 5.4 the short echo tag (<?=) is no longer to be consider a ‘short tag’ is always available regardless of the short_open_tag ini directive.

Naming Convention


Write all functions in camelBack:

function longFunctionName()


Class names should be written in CamelCase, for example:

class ExampleClass


Variable names should be as descriptive as possible, but also as short as possible. All variables should start with a lowercase letter, and should be written in camelBack in case of multiple words. Variables referencing objects should in some way associate to the class the variable is an object of. Example:

$user = 'John';
$users = ['John', 'Hans', 'Arne'];

$dispatcher = new Dispatcher();

Member Visibility

Use PHP5’s private and protected keywords for methods and variables. Additionally, non-public method or variable names start with a single underscore (_). Example:

class A
    protected $_iAmAProtectedVariable;

    protected function _iAmAProtectedMethod()
       /* ... */

    private $_iAmAPrivateVariable;

    private function _iAmAPrivateMethod()
        /* ... */

Example Addresses

For all example URL and mail addresses use “”, “” and “”, for example:

The “” domain name has been reserved for this (see RFC 2606) and is recommended for use in documentation or as examples.


File names which do not contain classes should be lowercased and underscored, for example:



For casting we use:

Cast to boolean.
Cast to integer.
Cast to float.
Cast to string.
Cast to array.
Cast to object.

Please use (int)$var instead of intval($var) and (float)$var instead of floatval($var) when applicable.


Constants should be defined in capital letters:

define('CONSTANT', 1);

If a constant name consists of multiple words, they should be separated by an underscore character, for example:


Careful when using empty()/isset()

While empty() is an easy to use function, it can mask errors and cause unintended effects when '0' and 0 are given. When variables or properties are already defined, the usage of empty() is not recommended. When working with variables, it is better to rely on type-coercion to boolean instead of empty():

function manipulate($var)
    // Not recommended, $var is already defined in the scope
    if (empty($var)) {
        // ...

    // Use boolean type coercion
    if (!$var) {
        // ...
    if ($var) {
        // ...

When dealing with defined properties you should favour null checks over empty()/isset() checks:

class Thing
    private $property; // Defined

    public function readProperty()
        // Not recommended as the property is defined in the class
        if (!isset($this->property)) {
            // ...
        // Recommended
        if ($this->property === null) {


When working with arrays, it is better to merge in defaults over using empty() checks. By merging in defaults, you can ensure that required keys are defined:

function doWork(array $array)
    // Merge defaults to remove need for empty checks.
    $array += [
        'key' => null,

    // Not recommended, the key is already set
    if (isset($array['key'])) {
        // ...

    // Recommended
    if ($array['key'] !== null) {
        // ...