Software quality

Basics

No globals

Do not use global variables like

$_POST
$_GET
$_SERVER
// etc.

In order to receive their represented values, use the methods provided by the shop framework.

No global functions

Avoid creating new global functions (e.g. in the modules/functions.php file).

No business logic in smarty functions

Use smarty only for design purposes. Business logic belongs to the PHP level.

PHP code

Object-oriented programming is highly preferred. Your code should be compatible with the PHP versions described in the system requirements.

OXID standards

Module Structure

The module’s directory structure should be as described in modules/structure.

Module constituents

All modifications introduced by a module must be part of the module directory. This applies for theme extensions, such as blocks, new templates, as well as language files and resources. A module must not come with manual modification instructions for templates or language files of the core product or 3rd party modules.

Class design

Base extensions

Your classes should, in general, be – directly or indirectly – derived from the Base (\OxidEsales\Eshop\Core\Base) class of the eShop framework. There are some exception where Base does not have to be used:

  • in classes where lazy loading is not needed (not directly working with database)
  • new classes intended for working with the file system

But you must inherit from Base,

  • when lazy loading is needed (for example like original shop file Article)
  • whenever you want to be able to access the shop’s configuration

Getters and setters

Accessing public variables of the class should be implemented using getter and setter methods.

Do not use $this->_aViewData

In the shop’s frontend templates, and unless you are not working with admin templates, do not use

$this->_aViewData['someVar'] = 'some Value';

Instead, use

$this->setViewData('someVar', 'some Value');

In general, keep in mind that setters and getters should be used whenever values are assigned to protected variables.

Exception handling

Create your own classes for exception handling and therefor use StandardException:

use \OxidEsales\Eshop\Core\Exception\StandardException

Maximum length of methods < 80 lines

The number of lines of a method should not be higher than 80. The best practice is to stich with values below 40. Modules with more than 120 lines of code in a method cannot be certified.

Complexity

Maximum NPath complexity < 200

The NPath complexity is the number of possible execution paths through a method. Each control structure, e.g.

if
elseif
for
while
case

is taken into account also the nested and multipart boolean expressions. The NPath complexity should be lower than 200. Modules with values above 500 cannot be certified.

Maximum Cyclomatic Complexity = 4

The Cyclomatic Complexity is measured by the number of statements of

if
while
do
for
?:
catch
switch
case

as well as operators like

&&
||
and
or
xor

in the body of a constructor, method, static initializer, or instance initializer. It is a measure of the minimum number of possible paths through the source and therefor the number of required tests. In general, 1-4 is considered good, 5-7 ok, 8-10 means “consider re-factoring”, and 11 and higher tells you “re-factor now!”. A hard limit for the module certification process is a Cyclomatic Complexity of 8.

Maximum C.R.A.P. index < 30

The Change Risk Analysis and Predictions (C.R.A.P.) index of a function or method uses Cyclomatic Complexity and Code Coverage from automated tests to help estimate the effort and risk associated with maintaining legacy code. Modules with a CRAP index above 30 will not be accepted in the certification process.

Extending views and frontend

Blocks

Use block definitions in the templates. This is not an obligation. The naming convention for new blocks is: [vendor]_[module]_[blockname]. In the templates, use blocks like that:

[{block name="thevendor_themodule_theblock"}][{/block}]

All blocks information should be stored into views/blocks directory:

For example, if a block is intended for a certain file of a theme, like Application/views/[theme name]/tpl/page/details/details.tpl, inside the module directory, the block file should be located in views/blocks/originalTemplateName_blockname.tpl.

When adding contents for blocks in the admin interface, blocks should be located in paths like views/blocks/admin/originalTemplateName_blockname.tpl.

Blocks sould be used whenever the shop’s functionality is extended to the frontend side and a requested function or method would not be available as long as the module is disabled. Using blocks allows you to move function calls into small snippet files for the frontend that are only included when the modules is set active. Therefore, using blocks can be considered a quality feature of a module.

Module templates

All new templates must be registered in metadata.php and should use naming convention:

[vendor]_[module]_[templateName]

All templates should be stored in the same structure like shop templates are.

For example:
views/ - all frontend templates views/admin/ - all admin templates

Using JavaScript and including .js files

JavaScript files should be stored into:

  • out/src/js/libs – if needs to define some additional JS libraries
  • out/src/js/widgets – all newly created widgets

Naming convention for new widgets: [vendor]_[module]_[widgetName].js

Important

All Javascript code must be in files in the widgets folder. Javascript code is not allowed directly in the template. In the template you are only allowed to do the assignment for widgets and do includes for the Javascript files you need.

In order to include Javascript files in frontend, use:

[{oxscript include=$oViewConf->getModuleUrl("[MODULE ID]", "out/src/js/[path where the needed file is] ") priority=10}]

And for output:

[{oxscript}]

Assignment of a DOM element for a widget:

[{oxscript add="$('dom element').neededWidget();" priority=10}]

In this way Javascript files will be included correctly within the template.

Using CSS and including .css files

CSS files should be stored in: out/src/css/<filename>

CSS file naming convention is: [vendor]_[module]_[css file name].css

To include new CSS file from module needs to use:

[{oxstyle include=$oViewConf->getModuleUrl("module id", "out/src/css/{FileName}.css")}]

And for output:

[{oxstyle}]

Important

All needed styles must be stored into CSS file and must not be assigned directly in template.

Language files and templates

Individual language files and templates must be inside the module directory.

Database access

Database access compatibility

Database access should be master-slave compatible. For details, see Database: Master/Slave.