Echoes from ZendCon Europe 2013

ZendCon is probably the biggest and most important conference in the PHP world. And for the first time it took place in Europe - Paris (18-20 November). Many brilliant and famous engineers, developers, speakers, entrepreneurs had their presentation there. Also some of the most important people  from Zend (“the PHP company”) were there to present new (and not so new) ideas, tools, best practices and to answer questions either from the stage in front of the audience or by the coffee stand
 in private.

My impression of the conference as a whole is that the API-centric and mobile-first principles will have growing importance in the future. That seems to be the main direction Zend is wishing to follow. At the same time automated continuous deployment is considered to be of great value in the software engineering process. And let’s not forget the “clouds”. They have been around for some time, but more and better integrated tools are being introduced either by the big players such as Google, Microsoft, IBM or by smaller but specialized vendors.

Cache patterns in PHP

No matter how skilled developer you are, sometimes you can't avoid having slow pieces of code - handling remote connections, database queries or just complicated calculations. One of the possible solutions is to implement caching. But the question is - how to do it right? In the following text I'll got through several possible ways how to implement caching in search of the best solution. I'll use the cache storage implementation from Zend Framework 2, but any other relevant implementation can be used instead.

Zend Framework 2 - the Logger factory

In Zend Framework 1 there was a nice factory method which allowed a logger object to be created with all its writers and filters just by passing an array or the corresponding Zend_Config value. In Zend Framework 2, there is no such method anymore. Probalby due to the effort to discourage the use of static factory methods. Anyway, it is still possible to do the same, although it is not so obvious.

OAuth2 / OpenID Connect Client Library for PHP/ZF2

I'm involved in federated identity management, delegated authorization and RESTful web services. So it was natural that I chose to adopt the OAuth2 framework and its more specific "brother" - OpenID Connect. There are already some client implementations of OpenID Connect and even more implementations of the OAuth2 specification. But I had my own reasons, why I wrote my own implementation:

• I use PHP, Zend Framework 2 and composer and I'm used to that :)
• instead of a monolitic client implementation I need a library/framework which provides tools and building blocks for creating clients for different use cases
• OpenID Connect is not ready yet, the specs are being changed and it is easier for me to modify and adapt my own implementation
• actually, I started writing a simple client to test my server implementation, but finally it grew up to a whole library :)

In the code I tried to respect the dependency injection paradigm together with the single responsibility principle and good testability. Dependencies may be injected or created implicitly in a "lazy" manner (when they are needed). As a result, the code is fragmented into numerous objects and it may need a bit more writing to tie them together (if you do not use the implicit values). That can be solved by writing a facade such as the InoOicClient\Flow\Basic object, which accepts a simple configuration array and does all the initialization inside.

I successfully tested the library against Google an Github, but probably more identity providers "work" out of the box. The source repository contains simple demos, but I'm planning to write more user-frienldy ones.

The library cannot be recommended for production use yet though. It hasn't been tested enough. There are some important features from the OpenID Connect specs missing - ID token validation, tools for discovery and registration etc. Anyway, I'm planning to add them in the future releases.

More information:

• GitHub repository - see the README for more technical info
• API docs

DokuWiki Shibboleth authentication plugin

The new DokuWiki version 2013-05-10 “Weatherwax” introduced new approach to modular authentication. While the older versions used authentication backends, the new version makes use of its flexible plugin system and introduces a new plugin type - the authentication plugin. Actually, it is very similar to the authentication backend, but as a plugin it provides all the benefits of the plugin system - it can be installed via DokuWiki administration, it can be configured with the configuration manager, etc.

That was an impulse for me to rewrite my Shibboleth authentication backend from scratch and implement it as a plugin. The old backend required a simple action plugin to intercept the login action and redirect the browser to the Shibboleth login handler. So it was necessary to install both the backend and the plugin. Now, when the authentication is done via plugins, only one plugin is required. The plugin system allows combination of different plugins in a single plugin bundle installed as one.

You can get the plugin from the new GitHub repository. See the README for instructions how to install it.

Links:

• GitHub repository
• Issues
• DokuWiki plugin page
• Old backend

Shiboleth authentication for Zend Framework 2

Some time ago I wrote a simple Shibboleth authentication adapter for ZF1. Now I finally  began using Zend Framework 2 for more complex projects, which require Shibboleth authentication. So I wrote a new version of the adapter to be used with ZF2. It can be used as a module or as a standalone library. The code is available through Composer. For more information see the GitHub repository.