json_encode PHP objects with their protected properties - php

Question

Is there any way I can set up PHP objects so that when I try to convert them to JSON, all of their protected properties will be shown?
I have read other answers suggesting I add a toJson() function to the object, but that may not really help me a great lot. In most cases, I have an array of objects and I perform the encode on the array itself.
$array = [
$object1, $object2, $object3, 5, 'string', $object4
];
return json_encode($array);
Yes, I can loop through this array and call toJson() on every element that has such method, but that just doesn't seem right. Is there a way I can use magic methods to achieve this?

Answer 1

You can implement the JsonSerializable interface in your classes so you have full control over how it is going to be serialized. You could also create a Trait to prevent copy pasting the serializing method:
<?php
trait JsonSerializer {
public function jsonSerialize()
{
return get_object_vars($this);
}
}
class Foo implements \JsonSerializable
{
protected $foo = 'bar';
use JsonSerializer;
}
class Bar implements \JsonSerializable
{
protected $bar = 'baz';
use JsonSerializer;
}
$foo = new Foo;
$bar = new Bar;
var_dump(json_encode([$foo, $bar]));
Alternatively you could use reflection to do what you want:
<?php
class Foo
{
protected $foo = 'bar';
}
class Bar
{
protected $bar = 'baz';
}
$foo = new Foo;
$bar = new Bar;
class Seriailzer
{
public function serialize($toJson)
{
$data = [];
foreach ($toJson as $item) {
$data[] = $this->serializeItem($item);
}
return json_encode($data);
}
private function serializeItem($item)
{
if (!is_object($item)) {
return $item;
}
return $this->getProperties($item);
}
private function getProperties($obj)
{
$rc = new ReflectionClass($obj);
return $rc->getProperties();
}
}
$serializer = new Seriailzer();
var_dump($serializer->serialize([$foo, $bar]));