Absensi Online menggunakan NodeMCU dan modul RFID RC522

• NodeMCU
• RC522 - RFID module
• I2C OLED 128x64
• Buzzer
• Kabel-kabel Jumper

• Arduino IDE
• Notepad ++ (text editor)
• XAMPP (Saya pakai versi 7.4)
• Postman (web API testing)

Membuat Web API

CREATE DATABASE IF NOT EXISTS absensi;
USE absensi;

/*Table structure for table `data_absen` */
CREATE TABLE data_absen (
  id int(100) NOT NULL AUTO_INCREMENT,
  tanggal date NOT NULL DEFAULT current_timestamp(),
  waktu time NOT NULL DEFAULT current_timestamp(),
  uid varchar(20) NOT NULL,
  status varchar(20) NOT NULL,
  PRIMARY KEY (id)
);

/*Table structure for table `data_invalid` */
CREATE TABLE data_invalid (
  id int(100) NOT NULL AUTO_INCREMENT,
  tanggal date NOT NULL DEFAULT current_timestamp(),
  waktu time NOT NULL DEFAULT current_timestamp(),
  uid varchar(10) NOT NULL,
  status varchar(10) NOT NULL,
  PRIMARY KEY (id)
);

/*Table structure for table `data_karyawan` */
CREATE TABLE data_karyawan (
  id int(50) NOT NULL AUTO_INCREMENT,
  created date NOT NULL DEFAULT current_timestamp(),
  uid varchar(20) NOT NULL,
  nama varchar(50) NOT NULL,
  division varchar(50) NOT NULL,
  mail varchar(50) NOT NULL,
  alamat text NOT NULL,
  picture varchar(100) NOT NULL,
  PRIMARY KEY (id)
);

<?php 
    class Database {
        private $host = "localhost";
        private $database_name = "absensi";
        private $username = "root";
        private $password = "";

        public $conn;

        public function getConnection(){
            $this->conn = null;
            try{
                $this->conn = new PDO("mysql:host=" . $this->host . ";dbname=" . $this->database_name, $this->username, $this->password);
                $this->conn->exec("set names utf8");
            }catch(PDOException $exception){
                echo "Database could not be connected: " . $exception->getMessage();
            }
            return $this->conn;
        }
    }  
?>

<?php
date_default_timezone_set('Asia/Jakarta');
class Absensi{
	// Connection
	private $conn;

	// Table
	private $db_table = "data_absen";
	private $db_table1 = "data_karyawan";
	private $db_table2 = "data_invalid";

	// Columns
	public $id;
	public $tanggal;
	public $waktu;
	public $uid;
	public $status;
	public $last_status;
	public $nama;

	// Db connection
	public function __construct($db){
		$this->conn = $db;
	}

	// CREATE
	public function createData(){
	//1. Cek user
		$sqlQuery = "SELECT * FROM ". $this->db_table1 ." WHERE uid = :uid LIMIT 0,1";
		$stmt = $this->conn->prepare($sqlQuery);
		$stmt->bindParam(":uid", $this->uid);
		$stmt->execute();
		if($stmt->errorCode() == 0) {
			while(($dataRow = $stmt->fetch(PDO::FETCH_ASSOC)) != false) {
				$this->nama = $dataRow['nama'];
			}
		} else {
			$errors = $stmt->errorInfo();
			echo($errors[2]);
		}
		$itemCount = $stmt->rowCount();
		
		if($itemCount > 0){
			//UID terdaftar -> cek status terakhir
			$sqlQuery = "SELECT data_absen.id, data_absen.uid, data_absen.status, data_karyawan.nama 
						FROM ". $this->db_table .", ". $this->db_table1 ."
						WHERE data_absen.id = (SELECT MAX(data_absen.id) 
						FROM ". $this->db_table ." WHERE data_absen.uid = :uid) 
						AND data_karyawan.uid= :uid";
			$stmt = $this->conn->prepare($sqlQuery);
			$stmt->bindParam(":uid", $this->uid);
			$stmt->execute();
			$itemCount = $stmt->rowCount();
			if($itemCount > 0){
				//error handling
				if($stmt->errorCode() == 0) {
					while(($dataRow = $stmt->fetch(PDO::FETCH_ASSOC)) != false) {
						$this->last_status = $dataRow['status'];
						$this->nama = $dataRow['nama'];
						//echo($this->last_status);
					}
				} else {
					$errors = $stmt->errorInfo();
					echo($errors[2]);
				}
			}else{
				$this->last_status ="OUT";
			}
			
			//set status
			if ($this->last_status == "IN"){
				$this->status = "OUT";
			}else{
				$this->status= "IN";
			}
			//Insert Data to data_absen	
			$sqlQuery = "INSERT INTO ". $this->db_table ."
					SET	waktu = :waktu, uid = :uid, status = :now_status";
						
			$this->waktu = date("H:i:s");
			
			$stmt = $this->conn->prepare($sqlQuery);
		
			// sanitize
			$this->uid=htmlspecialchars(strip_tags($this->uid));
		
			// bind data
			$stmt->bindParam(":uid", $this->uid);
			$stmt->bindParam(":now_status", $this->status);
			$stmt->bindParam(":waktu", $this->waktu);
		
			if($stmt->execute()){
			   return true;
			}
			return false;
		}
		else{
			//UID tidak terdaftar
			$this->status= "INVALID";
			$this->nama ="Invalid";
			
			//Insert Data to data_invalid	
			$sqlQuery = "INSERT INTO
						". $this->db_table2 ."
					SET
						waktu = :waktu,
						uid = :uid, 
						status = :now_status";
			$this->waktu = date("H:i:s");
			
			$stmt = $this->conn->prepare($sqlQuery);
		
			// sanitize
			$this->uid=htmlspecialchars(strip_tags($this->uid));
		
			// bind data
			$stmt->bindParam(":uid", $this->uid);
			$stmt->bindParam(":now_status", $this->status);
			$stmt->bindParam(":waktu", $this->waktu);
		
			if($stmt->execute()){
			   return true;
			}
			return false;
			
		}
		
	}
}
?>

{
    "waktu": "15:55:02",
    "nama": "Nama User",
    "uid": "B6B3C614",
    "status": "IN"
}

<?php
header("Access-Control-Allow-Origin: *");
header("Content-Type: application/json; charset=UTF-8");

include_once '../config/database.php';
include_once '../class/absensi.php';

$database = new Database();
$db = $database->getConnection();

$item = new Absensi($db);
$item->uid = isset($_GET['uid']) ? $_GET['uid'] : die('wrong structure!');
	
if($item->createData()){
	// create array
	$data_arr = array(
		"waktu" => $item->waktu,
		"nama" => $item->nama,
		"uid" => $item->uid,
		"status" =>  $item->status
	);
	http_response_code(200);
	echo json_encode($data_arr);
} else{
	http_response_code(404);
	echo json_encode("Failed!");
}
?>

http://localhost/absensi/webapi/api/create.php?uid=YOUR_UID_TAG

http://siab.arducoding-projects.online/webapi/api/create.php?uid=CARD_UID    //[GET]Proses Absensi
http://siab.arducoding-projects.online/webapi/api/get_last.php?uid=CARD_UID  //[GET] Cek Tap kartu terakhir