The Registry Package 
The Registry package provides an indexed key-value data store and an API for importing/exporting this data to several formats.
Load config by Registry
use Joomla\Registry\Registry;
$registry = new Registry;
// Load by string
$registry->loadString('{"foo" : "bar"}');
$registry->loadString('<root></root>', 'xml');
// Load by object or array
$registry->loadObject($object);
$registry->loadArray($array);
// Load by file
$registry->loadFile($root . '/config/config.json', 'json');Accessing a Registry by getter & setter
Get value
$registry->get('foo');
// Get a non-exists value and return default
$registry->get('foo', 'default');
// OR
$registry->get('foo') ?: 'default';Set value
// Set value
$registry->set('bar', $value);
// Sets a default value if not already assigned.
$registry->def('bar', $default);Accessing children value by path
$json = '{
"parent" : {
"child" : "Foo"
}
}';
$registry = new Registry($json);
$registry->get('parent.child'); // return 'Foo'
$registry->set('parent.child', $value);Removing values from Registry
// Set value
$registry->set('bar', $value);
// Remove the key
$registry->remove('bar');
// Works for nested keys too
$registry->set('nested.bar', $value);
$registry->remove('nested.bar');Accessing a Registry as an Array
The Registry class implements ArrayAccess so the properties of the registry can be accessed as an array. Consider the following examples:
// Set a value in the registry.
$registry['foo'] = 'bar';
// Get a value from the registry;
$value = $registry['foo'];
// Check if a key in the registry is set.
if (isset($registry['foo']))
{
echo 'Say bar.';
}Merge Registry
Using load* methods to merge two config files.
$json1 = '{
"field" : {
"keyA" : "valueA",
"keyB" : "valueB"
}
}';
$json2 = '{
"field" : {
"keyB" : "a new valueB"
}
}';
$registry->loadString($json1);
$registry->loadString($json2);Output
Array(
field => Array(
keyA => valueA
keyB => a new valueB
)
)
Merge another Registry
$object1 = '{
"foo" : "foo value",
"bar" : {
"bar1" : "bar value 1",
"bar2" : "bar value 2"
}
}';
$object2 = '{
"foo" : "foo value",
"bar" : {
"bar2" : "new bar value 2"
}
}';
$registry1 = new Registry(json_decode($object1));
$registry2 = new Registry(json_decode($object2));
$registry1->merge($registry2);If you just want to merge first level, do not hope recursive:
$registry1->merge($registry2, false); // Set param 2 to false that Registry will only merge first levelDump to one dimension
$array = array(
'flower' => array(
'sunflower' => 'light',
'sakura' => 'samurai'
)
);
$registry = new Registry($array);
// Make data to one dimension
$flatted = $registry->flatten();
print_r($flatted);The result:
Array
(
[flower.sunflower] => light
[flower.sakura] => samurai
)
Installation via Composer
Add "joomla/registry": "~2.0" to the require block in your composer.json and then run composer install.
{
"require": {
"joomla/registry": "~2.0"
}
}Alternatively, you can simply run the following from the command line:
composer require joomla/registry "~2.0"