Composer Autoloading

Question

I'm currently trying to use PSR-0 autoloading with Composer, but I'm getting the following error:

Fatal error: Class 'Twitter\Twitter' not found

My directory structure looks like this

- Project
    - src
        - Twitter
            Twitter.php
    - vendor
    - Test
    index.php

My index.php file looks like this:

<?php

    use Twitter;
    $twitter = new Twitter();

My Twitter.php file looks like this

<?php 

namespace Twitter;

class Twitter
{
    public function __construct()
    {
        // Code Here
    }
}

And finally my composer.json looks like this:

{
"require": {
    "phpunit/phpunit": "3.8.*@dev",
    "guzzle/guzzle": "3.7.*@dev"
},
"minimum-stability": "dev",
"autoload": {
    "psr-0": {
        "Twitter" : "src/Twitter"
    }
}
}

I am getting a little confused. I come from a C# background and this way of working is kinda confusing me. What's the correct way to use PSR-0 autoloading?

Answer 1

In your composer.json use:

"autoload": {
    "psr-0": {
        "": "src/"
    }
}

or

"autoload": {
    "psr-0": {
        "Twitter\\": "src/"
    }
}

and then run php composer.phar dump-autoload

Answer 2

Use

"psr-0": {
     "Twitter" : "src/"
 }

This instructs composer to create autoloader, that will look in src for everything from Twitter namespace. And since it is PSR-0, namespace is treated as a folder and added to declared path, so you should not include it in path part in composer.json