PHP JSON & API
Complete Guide in Hindi

// JSON — key-value pairs, arrays, nested objects
{
  "id": 1,
  "naam": "Rahul Kumar",
  "umar": 25,
  "active": true,
  "address": {
    "city": "Delhi",
    "pincode": "110001"
  },
  "skills": ["PHP", "MySQL", "Laravel"],
  "deleted_at": null
}

<?php
$user = [
  "id" => 1,
  "naam" => "राहुल",
  "email" => "rahul@gmail.com",
  "skills" => ["PHP", "MySQL"],
  "active" => true,
];

// Basic encode
echo json_encode($user);
// {"id":1,"naam":"\u0930\u093e\u0939\u0941\u0932",...}

// JSON_UNESCAPED_UNICODE — Hindi/Unicode as-is
echo json_encode($user, JSON_UNESCAPED_UNICODE);
// {"id":1,"naam":"राहुल",...}

// JSON_PRETTY_PRINT — readable format
echo json_encode($user, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE);
// {
// "id": 1,
// "naam": "राहुल",
// }

// JSON_UNESCAPED_SLASHES — URL में backslash नहीं
$url = ["link" => "https://example.com/path"];
echo json_encode($url); // "https:\/\/example.com\/path"
echo json_encode($url, JSON_UNESCAPED_SLASHES); // "https://example.com/path" ✅

// API response helper
function jsonResponse(mixed $data, int $code = 200): never {
  http_response_code($code);
  header("Content-Type: application/json; charset=UTF-8");
  echo json_encode($data, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
  exit;
}
?>

<?php
$json = '{"id":1,"naam":"Rahul","skills":["PHP","MySQL"],"active":true}';

// Default — stdClass object
$obj = json_decode($json);
echo $obj->naam; // Rahul
echo $obj->skills[0]; // PHP
echo $obj->active; // 1 (true)

// true — Associative array (recommended)
$arr = json_decode($json, true);
echo $arr["naam"]; // Rahul
echo $arr["skills"][1]; // MySQL

// Nested JSON decode
$nested = '{"user":{"naam":"Priya","address":{"city":"Mumbai"}}}';
$data = json_decode($nested, true);
echo $data["user"]["address"]["city"]; // Mumbai
?>

<?php
// Safe decode — error handle करो
function safeJsonDecode(string $json): array {
  $data = json_decode($json, true);
  if (json_last_error() !== JSON_ERROR_NONE) {
    throw new InvalidArgumentException(
      "JSON Error: " . json_last_error_msg()
    );
  }
  return $data ?? [];
}

// PHP 8.3+ — json_validate()
if (json_validate($jsonString)) {
  $data = json_decode($jsonString, true);
}

// json_last_error() codes
// JSON_ERROR_NONE — no error
// JSON_ERROR_DEPTH — max stack depth exceeded
// JSON_ERROR_SYNTAX — syntax error
// JSON_ERROR_UTF8 — malformed UTF-8
// JSON_ERROR_CTRL_CHAR — control char error
?>

<?php
// Basic GET request
function httpGet(string $url, array $headers = []): array {
  $ch = curl_init();
  curl_setopt_array($ch, [
    CURLOPT_URL => $url,
    CURLOPT_RETURNTRANSFER => true, // String return करो
    CURLOPT_TIMEOUT => 30, // 30 seconds max
    CURLOPT_HTTPHEADER => $headers,
    CURLOPT_SSL_VERIFYPEER => true, // SSL verify करो
    CURLOPT_USERAGENT => "HindiNotesPoint/1.0",
  ]);

  $response = curl_exec($ch);
  $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
  $error = curl_error($ch);
  curl_close($ch);

  if ($error) {
    throw new RuntimeException("cURL Error: $error");
  }
  return ["code" => $httpCode, "body" => $response];
}

// Usage
$result = httpGet("https://jsonplaceholder.typicode.com/users/1");
$user = json_decode($result["body"], true);
echo $user["name"];
?>

<?php
class HttpClient {
  private array $defaultHeaders = ["Accept: application/json"];
  private int $timeout = 30;

  public function withToken(string $token): static {
    $this->defaultHeaders[] = "Authorization: Bearer $token";
    return $this;
  }

  public function get(string $url, array $params = []): array {
    if ($params) $url .= "?" . http_build_query($params);
    return $this->request("GET", $url);
  }

  public function post(string $url, array $data = []): array {
    return $this->request("POST", $url, $data);
  }

  public function put(string $url, array $data = []): array {
    return $this->request("PUT", $url, $data);
  }

  public function delete(string $url): array {
    return $this->request("DELETE", $url);
  }

  private function request(string $method, string $url, array $data = []): array {
    $ch = curl_init();
    $headers = $this->defaultHeaders;
    $options = [
      CURLOPT_URL => $url,
      CURLOPT_RETURNTRANSFER => true,
      CURLOPT_TIMEOUT => $this->timeout,
      CURLOPT_CUSTOMREQUEST => $method,
      CURLOPT_SSL_VERIFYPEER => true,
    ];
    if ($data) {
      $body = json_encode($data);
      $headers[] = "Content-Type: application/json";
      $headers[] = "Content-Length: " . strlen($body);
      $options[CURLOPT_POSTFIELDS] = $body;
    }
    $options[CURLOPT_HTTPHEADER] = $headers;
    curl_setopt_array($ch, $options);
    $response = curl_exec($ch);
    $statusCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    $error = curl_error($ch);
    curl_close($ch);
    if ($error) throw new RuntimeException("cURL: $error");
    return [
      "status" => $statusCode,
      "data" => json_decode($response, true) ?? $response,
    ];
  }
}

// Usage — Method chaining
$client = (new HttpClient())->withToken("your-api-token");

// GET
$users = $client->get("https://api.example.com/users", ["page" => 1]);
// POST
$newUser= $client->post("https://api.example.com/users", ["naam" => "Rahul"]);
// DELETE
$del = $client->delete("https://api.example.com/users/42");
?>

<?php
header("Content-Type: application/json");
header("Access-Control-Allow-Origin: *"); // CORS

$method = $_SERVER["REQUEST_METHOD"];
$uri = parse_url($_SERVER["REQUEST_URI"], PHP_URL_PATH);
$parts = explode("/", trim($uri, "/"));
// /api/users/42 → ["api", "users", "42"]
$resource = $parts[1] ?? ""; // "users"
$id = isset($parts[2]) ? (int)$parts[2] : null;

// Request body (POST/PUT)
$body = json_decode(file_get_contents("php://input"), true) ?? [];
$pdo = getDB();

// Route — Users resource
if ($resource !== "users") {
  http_response_code(404);
  echo json_encode(["error" => "Resource not found"]);
  exit;
}

match($method) {
  "GET" => function() use ($pdo, $id) {
    if ($id) {
      $stmt = $pdo->prepare("SELECT id, naam, email FROM users WHERE id=?");
      $stmt->execute([$id]);
      $user = $stmt->fetch();
      if (!$user) { http_response_code(404); echo json_encode(["error" => "Not found"]); exit; }
      echo json_encode(["success" => true, "data" => $user]);
    } else {
      $users = $pdo->query("SELECT id, naam, email FROM users LIMIT 50")->fetchAll();
      echo json_encode(["success" => true, "data" => $users, "count" => count($users)]);
    }
  }(),

  "POST" => function() use ($pdo, $body) {
    $stmt = $pdo->prepare("INSERT INTO users (naam, email) VALUES (:naam, :email)");
    $stmt->execute([":naam" => $body["naam"] ?? "", ":email" => $body["email"] ?? ""]);
    http_response_code(201);
    echo json_encode(["success" => true, "id" => $pdo->lastInsertId()]);
  }(),

  "DELETE" => function() use ($pdo, $id) {
    $pdo->prepare("DELETE FROM users WHERE id=?")->execute([$id]);
    http_response_code(204);
  }(),

  default => function() {
    http_response_code(405);
    echo json_encode(["error" => "Method not allowed"]);
  }()
};
?>

<?php
// Token generate करो (Login endpoint)
function generateApiToken(int $userId): string {
  $token = bin2hex(random_bytes(32)); // Secure random
  $hash = hash("sha256", $token);
  $expires = date("Y-m-d H:i:s", strtotime("+30 days"));

  getDB()->prepare("INSERT INTO api_tokens (user_id, token_hash, expires_at) VALUES (?,?,?)")
         ->execute([$userId, $hash, $expires]);
  return $token; // Plain token return, hash नहीं
}

// Middleware — हर API request पर verify करो
function authenticate(): array {
  $auth = $_SERVER["HTTP_AUTHORIZATION"] ?? "";
  $token = str_replace("Bearer ", "", $auth);
  if (empty($token)) {
    http_response_code(401);
    die(json_encode(["error" => "Unauthorized — Token missing"]));
  }
  $hash = hash("sha256", $token);
  $stmt = getDB()->prepare("SELECT u.* FROM users u JOIN api_tokens t ON t.user_id=u.id WHERE t.token_hash=? AND t.expires_at > NOW()");
  $stmt->execute([$hash]);
  $user = $stmt->fetch();
  if (!$user) {
    http_response_code(401);
    die(json_encode(["error" => "Unauthorized — Invalid token"]));
  }
  return $user;
}

// Protected endpoint में use
$currentUser = authenticate(); // 401 if no valid token
echo json_encode(["profile" => $currentUser]);
?>

<?php
// 1. OpenWeatherMap API
function getWeather(string $city, string $apiKey): array {
  $url = sprintf(
    "https://api.openweathermap.org/data/2.5/weather?q=%s&appid=%s&units=metric",
    urlencode($city), $apiKey
  );
  $result = (new HttpClient())->get($url);
  return [
    "city" => $result["data"]["name"],
    "temperature" => $result["data"]["main"]["temp"],
    "description" => $result["data"]["weather"][0]["description"],
  ];
}
$weather = getWeather("Delhi", "your_api_key");
echo "Delhi: {$weather['temperature']}°C — {$weather['description']}";

// 2. SMS API (Twilio-style)
function sendSMS(string $to, string $message, string $apiKey): bool {
  $result = (new HttpClient())
    ->withToken($apiKey)
    ->post("https://api.smsprovider.com/send", [
      "to" => $to,
      "message" => $message,
    ]);
  return $result["status"] === 200;
}

// 3. Webhook receive करना
// POST /webhook/payment — Payment gateway callback
$payload = file_get_contents("php://input");
$signature = $_SERVER["HTTP_X_SIGNATURE"] ?? "";
$expected = hash_hmac("sha256", $payload, "webhook_secret");
if (!hash_equals($expected, $signature)) {
  http_response_code(401);
  die("Invalid webhook signature");
}
$event = json_decode($payload, true);
// Process payment event...
?>

<?php
// Consistent response format — always same structure
class ApiResponse {
  public static function success(mixed $data, string $message = "OK", int $code = 200): never {
    http_response_code($code);
    header("Content-Type: application/json");
    echo json_encode([
      "success" => true,
      "message" => $message,
      "data" => $data,
      "timestamp" => time(),
    ], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
    exit;
  }

  public static function error(string $message, int $code = 400, mixed $errors = null): never {
    http_response_code($code);
    header("Content-Type: application/json");
    echo json_encode([
      "success" => false,
      "message" => $message,
      "errors" => $errors,
      "timestamp" => time(),
    ]);
    exit;
  }
}

// Usage in endpoints
ApiResponse::success($users, "Users fetched");
ApiResponse::success($newUser, "User created", 201);
ApiResponse::error("Validation failed", 422, $errors);
ApiResponse::error("Not found", 404);
ApiResponse::error("Server error", 500);
?>