Json Serializer for PHP
This is a library to serialize PHP variables in JSON format. It is similar of the serialize()
function in PHP, but the output is a string JSON encoded. You can also unserialize the JSON generated by this tool and have you PHP content back.
Supported features:
- Encode/Decode of scalar, null, array
- Encode/Decode of objects
- Encode/Decode of binary data
- Support nested serialization
- Support not declared properties on the original class definition (ie, properties in
stdClass
) - Support object recursion
- Closures (via 3rd party library. See details below)
Unsupported serialization content:
- Resource (ie,
fopen()
response) - NAN, INF constants
Limitations:
- Binary data containing null bytes (\u0000) as array keys cannot be properly decoded because of a json extension bug:
This project should not be confused with JsonSerializable
interface added on PHP 5.4. This interface is used on json_encode
to encode the objects. There is no unserialization with this interface, differently from this project.
Json Serializer requires PHP >= 7.0 and tested until PHP 7.4
Example
class MyCustomClass {
public $isItAwesome = true;
protected $nice = 'very!';
}
$instance = new MyCustomClass();
$serializer = new Zumba\JsonSerializer\JsonSerializer();
$json = $serializer->serialize($instance);
// $json will contain the content {"@type":"MyCustomClass","isItAwesome":true,"nice":"very!"}
$restoredInstance = $serializer->unserialize($json);
// $restoredInstance will be an instance of MyCustomClass
How to Install
If you are using composer, install the package zumba/json-serializer
.
$ composer require zumba/json-serializer
Or add the zumba/json-serializer
directly in your composer.json
file.
If you are not using composer, you can just copy the files from src
folder in your project.
Serializing Binary Strings
Binary strings introduce two special identifiers in the final json: @utf8encoded
and @scalar
. @utf8encoded
is an array of keys from the original data which have their value (or the keys themselves) encoded from 8bit to UTF-8. This is how the serializer knows what to encode back from UTF-8 to 8bit when deserializing. Example:
$data = ['key' => '
'
, 'anotherkey' => 'nonbinaryvalue'];
$serializer = new Zumba\JsonSerializer\JsonSerializer();
$json = $serializer->serialize($data);
// $json will contain the content {"key":"
","anotherkey":"nonbinaryvalue","@utf8encoded":{"key":1}}
@scalar
is used only when the value to be encoded is not an array or an object but a binary string. Example:
$data = '
'
;
$serializer = new Zumba\JsonSerializer\JsonSerializer();
$json = $serializer->serialize($data);
// $json will contain the content {"@scalar":"
","@utf8encoded":1}
Serializing Closures
For serializing PHP closures you have to pass an object implementing SuperClosure\SerializerInterface
. This interface is provided by the project SuperClosure. This project also provides a closure serializer that implements this interface.
Closure serialization has some limitations. Please check the SuperClosure project to check if it fits your needs.
To use the SuperClosure with JsonSerializer, just pass the SuperClosure object as the first parameter on JsonSerializer constructor. Example:
$toBeSerialized = array(
'data' => array(1, 2, 3),
'worker' => function ($data) {
$double = array();
foreach ($data as $i => $number) {
$double[$i] = $number * 2;
}
return $double;
}
);
$superClosure = new SuperClosure\Serializer();
$jsonSerializer = new Zumba\JsonSerializer\JsonSerializer($superClosure);
$serialized = $jsonSerializer->serialize($toBeSerialized);
PS: JsonSerializer does not have a hard dependency of SuperClosure. If you want to use both projects make sure you add both on your composer requirements.
Custom Serializers
Some classes may not be suited to be serialized and unserialized using the default reflection methods.
Custom serializers provide the ability to define serialize
and unserialize
methods for specific classes.
class MyType {
public $field1;
public $field2;
}
class MyTypeSerializer {
public function serialize(MyType $obj) {
return array('fields' => $obj->field1 . ' ' . $obj->field2);
}
public function unserialize($values) {
list($field1, $field2) = explode(' ', $values['fields']);
$obj = new MyType();
$obj->field1 = $field1;
$obj->field2 = $field2;
return $obj;
}
}
// map of "class name" => Custom serializer
$customObjectSerializers['MyType'] = new MyTypeSerializer();
$jsonSerializer = new Zumba\JsonSerializer\JsonSerializer(null, $customObjectSerializers);
$toBeSerialized = new MyType();
$toBeSerialized->field1 = 'x';
$toBeSerialized->field2 = 'y';
$json = $jsonSerializer->serialize($toBeSerialized);
// $json == {"@type":"Zumba\\\\JsonSerializer\\\\Test\\\\SupportClasses\\\\MyType","fields":"x y"}
$myType = $jsonSerializer->unserialize($json);
// $myType == $toBeSerialized