Sami: Yet another PHP API documentation generator

Fabien Potencier

May 15, 2012

Today is my "let open source some of my private Github repositories" day, and more specifically, I'm releasing a bunch of code related to documentation.

Earlier today, I've released the Sphinx extensions I'm using to generate the Symfony documentation.

And now, I'm releasing my API documentation generator. Yes, I know that PHP already has a bunch of such generators, but I started to work on this project several years ago, when the only viable option was the old phpdocumentor.

Nowadays, phpDocumentor version 2 is probably the best option out there as it has a good architecture, it works fine, it is extensible, and quite a few big PHP projects is already using it. And that's fine. I don't want to compete with it, I don't want to replace it, I'm just open sourcing some code used by Symfony, Twig, and Silex because I'm not comfortable with closed-source software. And to be totally honest and transparent, I have not released the code before because it was not "good enough".

With this disclaimer out of the way, let's see what makes Sami "different" (compared to phpdocumentor)?

  • It uses a PHP file for configuration to give a very flexible way of tweaking the API generation;

  • It uses Twig for templating;

  • It uses a dependency injection container (Pimple) to let you override any internal class;

  • It only works with PHP 5.3 (but it can generate documentation for PHP 5.2 projects);

  • It uses the excellent PHP Parser project for PHP code parsing;

  • It is able to manage versions of your code to generate documentation for all of them in a single tree (without the overhead of re-parsing everything for each version of course).

Curious about what Sami generates? Have a look at the Symfony API.


First, get Sami from Github (or integrate it as a dependency in your project Composer file -- you are using Composer, right?):

You can also download an archive from Github.

As Sami uses Composer to manage its dependencies, installing it is a matter of running composer:

$ composer.phar install

Check that everything worked as expected by executing the sami.php file without any arguments:

$ php sami.php


Before generating documentation, you must create a configuration file. Here is the simplest possible one:

return new Sami\Sami('/path/to/symfony/src');

The configuration file must return an instance of Sami\Sami and the first argument of the constructor is the path to the code you want to generate documentation for.

Actually, instead of a directory, you can use any valid PHP iterator (and for that matter any instance of the Symfony Finder class):

use Sami\Sami;
use Symfony\Component\Finder\Finder;
$iterator = Finder::create()
return new Sami($iterator);

The Sami constructor optionally takes an array of options as a second argument:

return new Sami($iterator, array(
    'theme'                => 'symfony',
    'title'                => 'Symfony2 API',
    'build_dir'            => __DIR__.'/build',
    'cache_dir'            => __DIR__.'/cache',
    'default_opened_level' => 2,

And here is how you can configure different versions:

use Sami\Sami;
use Sami\Version\GitVersionCollection;
use Symfony\Component\Finder\Finder;
$iterator = Finder::create()
    ->in($dir = '/path/to/symfony/src')
// generate documentation for all v2.0.* tags, the 2.0 branch, and the master one
$versions = GitVersionCollection::create($dir)
    ->add('2.0', '2.0 branch')
    ->add('master', 'master branch')
return new Sami($iterator, array(
    'theme'                => 'symfony',
    'versions'             => $versions,
    'title'                => 'Symfony2 API',
    'build_dir'            => __DIR__.'/../build/sf2/%version%',
    'cache_dir'            => __DIR__.'/../cache/sf2/%version%',
    'default_opened_level' => 2,

To generate documentation for a PHP 5.2 project, simply set the simulate_namespaces option to true.


Now that we have a configuration file, let's generate the API documentation:

$ php sami.php update /path/to/config.php

The generated documentation can be found under the configured build/ directory (note that the client side search engine does not work on Chrome due to JavaScript execution restriction -- it works fine in Firefox).

By default, Sami is configured to run in "incremental" mode. It means that when running the update command, Sami only re-generates the files that need to be updated based on what has changed in your code since the last execution.

Sami also detects problems in your phpdoc and can tell you what you need to fix if you add the -v option:

$ php sami.php update /path/to/config.php -v

Creating a Theme

If the default themes do not suit your needs, you can very easily create a new one, or just override an existing one.

A theme is just a directory with a manifest.yml file that describes the theme (this is a YAML file):

name:   symfony
parent: enhanced

The above configuration creates a new symfony theme based on the enhanced built-in theme. To override a template, just create a file with the same name as the original one. For instance, here is how you can extend the default class template to prefix the class name with "Class " in the class page title:

{# pages/class.twig #}
{% extends 'default/pages/class.twig' %}
{% block title %}Class {{ parent() }}{% endblock %}

If you are familiar with Twig, you will be able to very easily tweak every aspect of the templates as everything has been well isolated in named Twig blocks.

A theme can also add more templates and static files. Here is the manifest for the default theme:

name: default
    'stylesheet.css':        'stylesheet.css'
    'index.twig':            'index.html'
    'namespaces.twig':       'namespaces-frame.html'
    'classes.twig':          'classes-frame.html'
    'pages/opensearch.twig': 'opensearch.xml'
    'pages/index.twig':      'doc-index.html'
    'pages/namespaces.twig': 'namespaces.html'
    'pages/interfaces.twig': 'interfaces.html'
    'pages/classes.twig':    'classes.html'
    'namespace.twig':        '%s/namespace-frame.html'
    'pages/namespace.twig':  '%s.html'
    'pages/class.twig':      '%s.html'

Files are contained into sections, depending on how Sami needs to treat them:

  • static: Files are copied as is (for assets like images, stylesheets, or JavaScript files);

  • global: Templates that do not depend on the current class context;

  • namespace: Templates that should be generated for every namespace;

  • class: Templates that should be generated for every class.

That's all there is to it for now. More documentation and a website is coming soon.


gravatar Luis Cordova  — May 15, 2012 14:20   #1
" and quite a few big PHP projects is already using it. " should be " and quite a few big PHP projects are already using it. "

nice outsource, definitely however why the repo misses all history and have just 1 commit? thought i could take a look and learn from the evolving

thanks looks good
gravatar Marc Morera  — May 15, 2012 14:52   #2
Is there any way to link any page?
I see all content is loaded by using AJAX, so if I want to share any page... Is there any url related to a simple page?

Nice work, as always ;)
gravatar Matthias Althaus  — May 15, 2012 15:12   #3
Nice works... could become handy for a current project of mine. :D
gravatar Benoit  — May 15, 2012 16:41   #4
Hello Fabien,

This is great news and seems to be a great project !

As a phpdocumentor2 I don't understand why you implied it is closed-source software ? IIRC its released under GPL license

gravatar Mike van Riel  — May 15, 2012 17:24   #5
I think that Fabien meant that he didn't like it that the tools that he made and uses were closed-source.

Also: phpDocumentor 2 is licensed under the MIT license.
gravatar Fabien Potencier  — May 15, 2012 17:45   #6
I agree that this is not clear enough but Mike is right, I meant that I don't like writing closed-source software, and everything I write is always Open-Sourced at some point.
gravatar Gunnar Lium  — May 15, 2012 20:35   #7
What's the story behind the name?
gravatar Andrew Embler  — May 15, 2012 20:43   #8
This looks great. Really easy to install and get started with.

Off the top of your head...any idea how easy it would be to make simulate_namespaces work with phpDocumentor style "package" or "subpackage" tags in the documentation block rather than a using the actual prefix of the class? I'd love to be able to group our classes in the left navigation, but we don't use namespaces and our classes don't conform to that standard.

This looks great!
gravatar Marijn Huizendveld  — May 15, 2012 23:14   #9
This was really easy to set up :-) Finally lovely documentation, I'm really, really happy with this!

I was wondering what way we could support array inner types. E.g. JMSSerializerBundle uses @Type array<key, value>. Have you settled for a standard or could we implement something like in JMSSerializerBundle?

Thanks again!
gravatar Fabien Potencier  — May 16, 2012 08:11   #10
@Marijn: It should be possible to implement that as an extension. I can help you find the best way to do that if you want.
gravatar Beau Simensen  — May 16, 2012 17:36   #11
Excellent! I've been looking forward to seeing this code for quite some time. Thanks Fabien!
gravatar Jan Marek  — May 17, 2012 07:32   #12
Hi Fabien, have you tried Apigen used by Doctrine?
gravatar Daniele Cesarini  — May 17, 2012 08:29   #13
Great as ever. I'm also interested in sphinx extension, does it contain also a way to include sphinx output in a symfony2 website? (like symfony documentation)
gravatar Wil Moore  — June 04, 2012 19:56   #14
Nicely done.