[3.0] Refactored to use environment variables object

[GrahamCampbell]

Closes #208. Closes #214.

[GrahamCampbell]

Some examples.

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Example 1

The following example assumes $path is the full path of the directory containing your .env file.

This example will load the .env file, returning the variables, AND will have the side effect of mutating your environment.

<?php

use Dotenv\Dotenv;

$dotenv = Dotenv::create($path);

$variables = $dotenv->load();

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Example 2

The following example assumes $path is the full path of the directory containing your .env file.

Similar to the first example, only this time we avoid calling any non-thread-safe functions.

<?php

use Dotenv\Environment\Adapter\EnvConstAdapter;
use Dotenv\Environment\Adapter\ServerConstAdapter;
use Dotenv\Environment\DotenvFactory;
use Dotenv\Dotenv;

$factory = new DotenvFactory([new EnvConstAdapter(), new ServerConstAdapter()]);

Dotenv::create($path, null, $factory)->load();

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EXAMPLE 3

The following example assumes $path is the full path of the directory containing your .env file.

This example will load the .env file, returning the variables, BUT will not mutate your current environment. This is because, in example 1, the default factory was used, so the adapters that mess with your actual environment are used.

<?php

use Dotenv\Environment\Adapter\ArrayAdapter;
use Dotenv\Environment\DotenvFactory;
use Dotenv\Dotenv;

$dotenv = Dotenv::create($path, null, new DotenvFactory([new ArrayAdapter()]));

$variables = $dotenv->load();

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EXAMPLE 4

The following example assumes $content contains the actual content of your env file:

Once again, this example will not mutate your actual environment, allowing you to inspect the contents of an env file in isolation.

<?php

use Dotenv\Environment\Adapter\ArrayAdapter;
use Dotenv\Environment\DotenvFactory;
use Dotenv\Loader;

$loader = new Loader([], new DotenvFactory([new ArrayAdapter()]));

$variables = $loader->loadDirect($content));