Servidor JSON Simples com PHP para testes

index.php

<?php
header('Content-type: application/json');
$method = $_SERVER['REQUEST_METHOD'];
$body = file_get_contents('php://input'); // request body

if (!file_exists('./db.json'))
	file_put_contents('db.json', '{}');

$contents = file_get_contents('db.json');
$json = json_decode($contents, true); // true: stdClass => array associativo

if (!array_key_exists('path', $_GET))
  die('{"error":"Path missing (?path=resource)"}');

$path = explode('/', $_GET['path']);

if (count($path) == 0 || $path[0] == '')
  die('{"error":"Path missing (series/genres)"}');

$param1 = count($path) > 1 ? $path[1] : '';

function findById($array, $id) {
	$posicao = -1;
	foreach ($array as $key => $value) {
		if ($value['id'] == $id) {
			$posicao = $key;
			break;
		}
	}
	return $posicao;
}

if ($method == 'GET') {
  if ($json[$path[0]]) {
  	if($param1 == '')
	    echo json_encode($json[$path[0]]);
  	else {
  		$posicao = findById($json[$path[0]], $param1);
  		if ($posicao < 0)
				die('{"error":"not found"}');
  		echo json_encode($json[$path[0]][$posicao]);
  	}

  } else {
    echo '[]';
  }
}

if ($method == 'POST') {
	if (!is_array(json_decode($body, true)))
		die('{"error":"body needs to be a valid json"}');
  $jsonBody = json_decode($body, true);
  $jsonBody['id'] = uniqid();

  if(!$json[$path[0]])
    $json[$path[0]] = [];
  
  $json[$path[0]][] = $jsonBody;
  echo json_encode($jsonBody);
  file_put_contents('db.json', json_encode($json));

}

if ($method == 'DELETE') {
  if ($json[$path[0]]) {
  	if($param1 == '')
	    die('{"error": "missing id"}');
  	else {
  		$posicao = findById($json[$path[0]], $param1);
  		if ($posicao < 0)
				die('{"error":"not found"}');
			unset($json[$path[0]][$posicao]);
			file_put_contents('db.json', json_encode($json));
  		echo '{"success":"deleted"}';
  	}

  } else {
    echo '[]';
  }
}

if ($method == 'PUT') {
  if ($json[$path[0]]) {
  	if($param1 == '')
	    die('{"error": "missing id"}');
  	else {
  		$posicao = findById($json[$path[0]], $param1);
  		if ($posicao < 0)
				die('{"error":"not found"}');
			if (!is_array(json_decode($body, true)))
				die('{"error":"body needs to be a valid json"}');
			$jsonBody = json_decode($body, true);
			$jsonBody['id'] = $param1;
			$json[$path[0]][$posicao] = $jsonBody;
			file_put_contents('db.json', json_encode($json));
  		echo json_encode($jsonBody);
  	}

  } else {
    echo '[]';
  }
}