JsonDecoder for PHP

This package contains a JsonDecoder implementation that allows you to convert your JSON data into php class objects other than stdclass.

Installation

You can install the package via composer

composer require karriere/json-decoder

Usage

By default all public properties of the class will be inspected. For all properties that have a JSON key with the same name the according value will be set.

A simple example

Assume you have a class Person that looks like this:

class Person
{
    public $id;
    public $name;
}

The following code will transform the given JSON data into an instance of Person.

$jsonDecoder = new JsonDecoder();
$jsonData = '{"id": 1, "name": "John Doe"}';

$person = $jsonDecoder->decode($jsonData, Person::class);

Defining a Transformer

Let's extend the previous example with a property called address. This address field should contain an instance of Address.

class Person
{
    public $id;
    public $name;
    public $address;
}

To be able to transform the address data into an Address class object you need to define a transformer for Person:

The transformer interface defines two methods:

• register: here you register your field, array, alias and callback bindings
• transforms: gives you the full qualified class name e.g.: Your\Namespace\Class

class PersonTransformer implements Transformer
{
    public function register(ClassBindings $classBindings)
    {
        $classBindings->register(new FieldBinding('address', 'address', Address::class);
    }

    public function transforms()
    {
        return Person::class;
    }
}

After registering the transformer the JsonDecoder will use the defined transformer:

$jsonDecoder = new JsonDecoder();
$jsonDecoder->register(new PersonTransformer());

$jsonData = '{"id": 1, "name": "John Doe"}';

$person = $jsonDecoder->decode($jsonData, Person::class);

Handling private and protected properties

The JsonDecoder class accepts two boolean constructor parameters to enable the handling of private and protected properties.

To do so a so called PropertyAccessor will be installed and on property set the proxy will set the property to accessible, set the according value and then will set the property to not accessible again.

Transforming an array of elements

If your JSON contains an array of elements at the root level you can use the decodeMultiple method to transform the JSON data into an array of class type objects.

$jsonDecoder = new JsonDecoder();

$jsonData = '[{"id": 1, "name": "John Doe"}, {"id": 2, "name": "Jane Doe"}]';

$personArray = $jsonDecoder->decodeMultiple($jsonData, Person::class);

Documentation

Transformer Bindings

The following Binding implementations are available

• FieldBinding
• ArrayBinding
• AliasBinding
• CallbackBinding

FieldBinding

Defines a JSON field to property binding for the given type.

Signature:

new FieldBinding($property, $jsonField, $type);

This defines a field mapping for the property $property to a class instance of type $type with data in $jsonField.

ArrayBinding

Defines a array field binding for the given type.

Signature:

new ArrayBinding($property, $jsonField, $type);

This defines a field mapping for the property $property to an array of class instance of type $type with data in $jsonField.

AliasBinding

Defines a JSON field to property binding.

Signature:

new AliasBinding($property, $jsonField);

CallbackBinding

Defines a property binding that gets the callback result set as its value.

Signature:

new CallbackBinding($property, $callback);

License

Apache License 2.0 Please see LICENSE for more information.