Using Selected PHP Frameworks in Async Mode

There are a number of other PHP frameworks that implement the asynchronous programming model. We cover ReactPHP, the most popular of the PHP async frameworks, as well as Amp, another popular PHP async framework. In addition, we show how selected PHP frameworks can be used in async mode.

It’s important to note that many of the PHP frameworks able to operate in asynchronous mode have a dependency on the Swoole extension. The one that does not have this dependency is ReactPHP, covered next.

Working with ReactPHP

ReactPHP is an implementation of the Reactor software design pattern and was inspired by the non-blocking asynchronous Node.js framework among others.

Although ReactPHP does not give us the automatic performance increase seen with the Swoole extension, it has a big advantage in that it does not rely upon features of UNIX or Linux and can thus run on a Windows server. The other advantage of ReactPHP is that it has no specific dependency on PHP extensions other than those already included as standard extensions.

The core of any ReactPHP application is the React\EventLoop\Loop class. As the name implies, a Loop instance starts up effectively as an infinite loop. Most PHP infinite loops spell disaster for our application! In this case, however, the loop is used with a server instance that continuously listens to requests on a given port.

Another key component of ReactPHP is React\Socket\Server. This class opens a socket on the given port, enabling a ReactPHP application to listen for HTTP requests directly without having to involve a web server.

Other features of ReactPHP include the ability to listen for UDP requests, a nonblocking cache, and the implementation of async promises. ReactPHP also features a Stream component that allows us to defer filesystem reads and writes, greatly speeding up ...