In this episode, I’m looking at PSR-7, the second of two core components which Zend Expressive is built on. Zend Framework team lead, Matthew Weier O'Phinney describes it as:

a set of standard HTTP message interfaces so that we can create an ecosystem in which PHP developers can create re-usable middleware that they can share.

The PSR site describes it as:

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.

To find out more information on it, check out these key links:

• https://mwop.net/blog/2015-01-08-on-http-middleware-and-psr-7.html
• http://www.php-fig.org/psr/psr-7/
• http://www.masterzendframework.com/zend-expressive-introduction/
• https://github.com/zendframework/zend-expressive

Questions/Comments/Suggestions

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