# PHP Standard Recommendation

The PHP Standard Recommendation (PSR) is a PHP specification published by the PHP Framework Interop Group. Similar to Java Specification Request for Java, it serves the standardization of programming concepts in PHP. The aim is to enable interoperability of components and to provide a common technical basis for implementation of proven concepts for optimal programming and testing practices. The PHP-FIG is formed by several PHP frameworks founders.
Each PSR is suggested by members and voted according to an established protocol to act consistently and in line with their agreed upon processes.
| Number | Name | Description | Editor | Coordinator | Sponsor | Status |
| PSR-0 | Autoloading Standard | It describes the mandatory requirements that must be adhered to for autoloader interoperability. | N/A | N/A | N/A | Deprecated and substituted by PSR-4 |
| PSR-1 | Basic Coding Standard | It comprises what should be considered the standard coding elements that are required to ensure a high level of technical interoperability between shared PHP code. | N/A | N/A | N/A | Accepted |
| PSR-2 | Coding Style Guide | It considers PSR-1 and it is intended to reduce cognitive friction when scanning code from different authors. It does so by enumerating a shared set of rules and expectations about how to format PHP code. | N/A | N/A | N/A | Deprecated |
| PSR-3 | Logger Interface | It describes a common interface for logging libraries. | Jordi Boggiano | N/A | N/A | Accepted |
| PSR-4 | Autoloading Standard | It describes a specification for autoloading classes from file paths. It is fully interoperable, and can be used in addition to any other autoloading specification, including PSR-0. This PSR also describes where to place files that will be auto loaded according to the specification. | Paul M. Jones | Phil Sturgeon | Larry Garfield | Accepted |
| PSR-5 | PHPDoc Standard | The main purpose of this PSR is to provide a complete and formal definition of the PHPDoc standard. This PSR deviates from its predecessor, the de facto PHPDoc Standard associated with phpDocumentor 1.x, to provide support for newer features in the PHP language and to address some of the shortcomings of its predecessor. | Mike van Riel | Phil Sturgeon | Donald Gilbert | Draft |
| PSR-6 | Caching Interface | The goal of this PSR is to allow developers to create cache-aware libraries that can be integrated into existing frameworks and systems without the need for custom development. | Larry Garfield | Paul Dragoonis | Robert Hafner | Accepted |
| PSR-7 | HTTP Message Interface | It describes common interfaces for representing HTTP messages as described in RFC 7230 and RFC 7231, and URIs for use with HTTP messages as described in RFC 3986. | Matthew Weier O'Phinney | Beau Simensen | Paul M. Jones | Accepted |
| PSR-8 | Huggable Interface | It establishes a common way for objects to express mutual appreciation and support by hugging. This allows objects to support each other in a constructive fashion, furthering cooperation between different PHP projects. | Larry Garfield | Cal Evans | Paul M. Jones | Abandoned |
| PSR-9 | Security Disclosure | It gives project leads a clearly defined approach to enabling end users to discover security disclosures using a clearly defined structured format for these disclosures. | Lukas Kahwe Smith | Korvin Szanto | Larry Garfield | Abandoned |
| PSR-10 | Security Advisories | It gives researchers, project leads, upstream project leads and end users a defined and structured process for disclosing security vulnerabilities. | Lukas Kahwe Smith | Larry Garfield | Korvin Szanto | Abandoned |
| PSR-11 | Container Interface | It describes a common interface for dependency injection containers. The goal is to standardize how frameworks and libraries make use of a container to obtain objects and parameters (called entries in the rest of this document). | Matthieu Napoli, David Négrier | Paul M. Jones | Jeremy Lindblom | Accepted |
| PSR-12 | Extended Coding Style Guide | It extends, expands and replaces PSR-2, the coding style guide and requires adherence to PSR-1, the basic coding standard. | Michael Cullum | Korvin Szanto | Alexander Makarov | Accepted |
| PSR-13 | Hypermedia Links | It describes common interfaces for representing a hypermedia link. | Larry Garfield | Matthew Weier O’Phinney | Marc Alexander | Accepted |
| PSR-14 | Event Manager | It describes common interfaces for dispatching and handling events. | Larry Garfield | | | Accepted |
| PSR-15 | HTTP Server Request Handlers | It describes common interfaces for HTTP server request handlers and HTTP server middleware components that use HTTP messages. | Woody Gilk | | Matthew Weier O’Phinney | Accepted |
| PSR-16 | Simple Cache | It describes a simple yet extensible interface for a cache item and a cache driver. | Paul Dragoonis | Jordi Boggiano | Fabien Potencier | Accepted |
| PSR-17 | HTTP Factories | It describes a common standard for factories that create PSR-7 compliant HTTP objects. | Woody Gilk | | Matthew Weier O’Phinney | Accepted |
| PSR-18 | HTTP Client | It describes a common interface for sending HTTP requests and receiving HTTP responses. | Tobias Nyholm | | Sara Golemon | Accepted |
| PSR-19 | PHPDoc tags | It provides a complete catalog of tags in the PHPDoc standard. | Chuck Burgess | | | Draft |
| PSR-20 | Clock | It provides a standard way of accessing the clock - allowing interopability during testing, when testing behavior that has timing based side effects. | Chris Seufert | | Chuck Burgess | Accepted |
| PSR-21 | Internationalization | TBD. | Navarr Barnier | | | Draft |
| PSR-22 | Application Tracing | TBD. | Adam Allport | | | Draft |
The PHP-FIG official website has the PSR documentation that follows the RFC 2119 written by Scott Bradner in March 1997 at Harvard University.