PHP Developers: start here #

This section of the help is for PHP developers who write PHP code on or for Exponential: kernel fixes, extensions, modules and views, datatypes, persistent objects, fetch functions, template operators, workflow event types, cronjob parts, commands, JSON and REST endpoints, and the tests that go with them. It explains the code base's conventions, the rules the project checks on every change, and how code behaves under each runtime, with real class names, files and commands of the repository.

Every statement on these pages was checked against the code, the settings or the existing documentation of the 6.0.15 line. Where these pages overlap with the pages for application creators and the extension developer book, they link to them instead of repeating them.

Contents #

1. Exponential in one paragraph, for PHP developers
2. Your first hour
3. Seven rules for every PHP change
4. Map of the PHP developer pages
5. Pages from other audiences you will use
6. Finding these pages again

Exponential in one paragraph, for PHP developers #

Exponential is a free and open source PHP content management system and application framework, licensed under the GNU GPL, version 2 or later. Its code base has been developed since 1999, first under the name eZ Publish, a product its creator discontinued after almost 18 years; 7x kept it alive, and it is led by 7x together with the Exponential Foundation (Who is 7x?, Who is the Exponential Foundation?). For a PHP developer it is a large, mature code base with its own conventions: PHP 8.0 to 8.5 (PHP 7.4 usable without support), generated class maps instead of PSR-4, layered INI settings read through eZINI, eZPersistentObject for tables, a compiled template language, six supported databases (SQLite 3 by default, PostgreSQL, MongoDB, MariaDB, Oracle, MySQL), and Velocity, an application server with persistent workers, as part of the product (Exponential for PHP developers).

Your first hour #

1. Orient yourself (10 minutes): Exponential for PHP developers and A tour of the source tree.
2. Follow one request (10 minutes): How a request runs in PHP.
3. Set up a checkout (20 minutes): Setting up a PHP development checkout, with make devtools and make hooks.
4. Learn the rules (10 minutes): Writing code that runs on PHP 8.0 and The coding standard.
5. Build something (10 minutes to start): Write your first module view.

The whole section in order is The PHP developer's reading path.

Seven rules for every PHP change #

1. Runs on PHP 8.0 to 8.5 (PHP 7.4 usable without support). No syntax or unguarded function newer than 8.0 (Writing code that runs on PHP 8.0).
2. Follows the house style. array(), spaces inside parentheses, no type declarations; make phpcs and make phpstan add nothing (The coding standard).
3. Is named with a prefix. exp for project code, your own for yours; kernel eZ* identifiers never change (Class naming and the exp prefix).
4. Trusts no input and escapes all output. Casts, allow lists, escapeString(), |wash, the form token, permission checks in every entry point (Security in PHP code).
5. Keeps no state between requests. Correct under Velocity's persistent workers (Static state traps).
6. Works on every supported database. Portable SQL or persistent objects (Code for every supported database).
7. Comes with a test. DB-less where possible (PHPUnit without a database).

Map of the PHP developer pages #

Orientation #

PHP versions and code rules #

Building blocks #

Data and APIs #

Security #

Debugging and performance #

Runtimes #

Tests, quality and contributing #

Reference #

Pages from other audiences you will use #

Finding these pages again #

• In the help, filter by the audience PHP Developers, or open All pages and the folder php-developers.
• Each page has Edit on GitHub. If a statement here no longer matches the code, tell us there or on the community issue tracker.

Related pages #

• Exponential for PHP developers
• The PHP developer's reading path
• Application creators: start here
• Writing migrations in PHP, Migrations
• Free documentation: this page is free to copy, translate and improve under the GNU FDL 1.3.