Event Loop Interopability

The purpose of this proposal is to provide a common interface for event loop implementations. This will allow libraries and components from different vendors to operate in an event driven architecture, sharing a common event loop.

Why Bother?

Some programming languages, such as Javascript, have an event loop that is native to the execution environment. This allows package vendors to easily create asynchronous software that uses this native event loop. Although PHP is historically a synchronous programming environment, it is still possible to use asynchronous programming techniques. Using these techniques, package vendors have created PHP event loop implementations that have seen success.

However, as these event loop implementations are from package vendors, it is not yet possible to create event driven software components that are independent of the underlying event loop implementation. By creating a common interface for an event loop, interoperability of this nature will be possible.

Goals

The functionality exposed by this interface should include the ability to:

• Watch input streams for available data
• Watch output streams for the ability to perform non-blocking write operations
• Run single and periodic timers
• Listen for signals
• Defer the execution of callables

Contributors

• Aaron Piotrowski
• Andrew Carter
• Bob Weinand
• Cees-Jan Kiewiet
• Christopher Pitt
• Daniel Lowrey
• Niklas Keller
• Stephen M. Coakley