Simple HMVC Restful API — Node Js, Express Js, MySQL

Langsung saja ya 😄

Saya ingin berbagi tentang tutorial membuat modular HMVC (Hierarchical Model View Controller). Tutorial ini sebenarnya berdasarkan pada project brizkoder yang kemudian saya modifikasi sendiri. Struktur project yang saya modifikasi menggunakan konsep HMVC yaitu membagi setiap modul project yang di dalamnya terdapat Model, View dan Controller. Seperti berikut ini:

Struktur HMVC

Mungkin saya hanya menjelaskan garis besarnya saja karena saya rasa sudah banyak yang membahas tentang NodeJs & ExpressJS.

server.js untuk mengatur Express Webserver

const express = require("express");
const bodyParser = require("body-parser");const app = express();// parse requests of content-type - application/json
app.use(bodyParser.json());// parse requests of content-type - application/x-www-form-urlencoded
app.use(bodyParser.urlencoded({ extended: true }));require("./app/config/config.router.js")(app);// set port, listen for requests
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log(`Server is running on port ${PORT}.`);
});

Pada folder config terdapat 2 file yaitu config.db.js dan config.router.js.

config.db.js untuk configurasi DB silahkan sesuaikan sendiri

module.exports = {
    HOST: "localhost",
    USER: "root",
    PASSWORD: "root",
    DB: "node-project"
  };

config.router.js untuk menangani semua CRUD dari setiap modul

module.exports = app => {
    
    app.get("/", (req, res) => {
        res.json({ message: "Welcome to application." });
      });require("../modules/customers/routers/customer.routes.js")(app);
};

Di folder core terdapat 2 file yaitu core.connection.js dan core.model.js.

core.connection.js untuk menghubungkan project dengan DB

const mysql = require("mysql");
const dbConfig = require("../config/config.db.js");const connection = mysql.createConnection({
  host: dbConfig.HOST,
  user: dbConfig.USER,
  password: dbConfig.PASSWORD,
  database: dbConfig.DB
});connection.connect(error => {
  if (error) throw error;
  console.log("Successfully connected to the database.");
});module.exports = connection;

core.model.js untuk beroperasi dengan DB. Disini saya memodifikasi beberapa baris kode yang nantinya bisa digunakan pada beberapa modul.

//modified by Puguh Jayadiconst connection = require("../core/core.connection.js");
const express = require('express');
const app = express();
const PORT = process.env.PORT || 3000;module.exports = function(table) {return {paginate : function(object, result) {
      const host      = object.protocol+"://"+object.hostname+":"+PORT;
      const per_page  = (object.query.per_page) ? parseInt(object.query.per_page) : 10;
      const page      = (object.query.page) ? parseInt(object.query.page) : 1;
      const search    = (object.query.search) ? object.query.search : '';
      const offset    = (page - 1) * per_page;
      const whereLike = this.whereLike(object.column, search);
      const queryBase = "SELECT * FROM "+table;
      const queryLimit = queryBase+" WHERE "+ whereLike.columns +" limit "+per_page+" OFFSET "+offset;
      
      if(search != ''){
        querySearch= queryBase+" WHERE "+whereLike.columns;
      } else {
        querySearch= queryBase;
      }connection.query(querySearch, whereLike.search, (err, rows) => {
        let tot = parseInt(rows.length);
        let first_page = 1;
        let previous_page = page > 0 ? page - 1 : "null";
        let next_page = page < Math.ceil(tot / per_page) ? page + 1 : "null";
        let last_page = Math.ceil(tot / per_page);connection.query(queryLimit, whereLike.search, (err, res) => {
          if (err) {
            console.log("error: ", err);
            result(err, null);
            return;
          }response = {
            search : search,
            total : tot,
            per_page : per_page,
            previous_page : previous_page,
            current_page : page,
            last_page : last_page,
            first_page_url: host+object.path + "?search="+search+"&page="+first_page+"&per_page="+per_page,
            last_page_url: host+object.path + "?search="+search+"&page="+last_page+"&per_page="+per_page,
            previous_page_url: (previous_page != 0) ? host+object.path + "?search="+search+"&page="+previous_page+"&per_page="+per_page : "null",
            next_page_url: (next_page != "null") ? host+object.path + "?search="+search+"&page="+next_page+"&per_page="+per_page : "null",
            path : host + object.path,
            from : offset + 1,
            to : offset + res.length,
            data : res
          }result(null, response);
        });
      });
    },all : function(result) {
      connection.query("SELECT * FROM "+table, (err, res) => {
        if (err) {
          console.log("error: ", err);
          result(err, null);
          return;
        }
        result(null, res);
      });
    },nums : function(result) {
      connection.query("SELECT COUNT(*) AS nums FROM "+table, (err, res) => {
        if (err) {
          console.log("error: ", err);
          result(err, null);
          return;
        }
        result(null, res);
      });
    },store : function (object, result) {
      connection.query("INSERT INTO "+table+" SET ?", object, (err, res) => {
        if (err) {
          console.log("error: ", err);
          result(err, null);
          return;
        }console.log("created object: ", { id: res.insertId, ...object });
        result(null, { id: res.insertId, ...object });
      });
    },show : function(id, result) {
      connection.query("SELECT * FROM "+table+" WHERE id = ?", [id], (err, res) => {
        if (err) {
          console.log("error: ", err);
          result(err, null);
          return;
        }
        if (res.length) {
          console.log("found object: ", res[0]);
          result(null, res[0]);
          return;
        }result(null, { message: "not found" });});
    },update : function (id, object, result) {
      connection.query( "UPDATE "+table+" SET ? WHERE id = ?", [object, id], (err, res) => {
        if (err) {
          console.log("error: ", err);
          result(null, err);
          return;
        }if (res.affectedRows == 0) {
          result(null, { message: "not found" });
          return;
        }console.log("updated object: ", { id: id, ...object });
        result(null, { id: id, ...object });
      }
      );
    },destroy : function(id, result) {
      connection.query("DELETE FROM "+table+" WHERE id = ?", id, (err, res) => {
        if (err) {
          console.log("error: ", err);
          result(null, err);
          return;
        }if (res.affectedRows == 0) {
          result(null, { message: "not found" });
          return;
        }console.log("deleted object with id: ", id);
        result(null, res);
      });
    },whereLike : function(columns, search) {
      return {
        columns : columns.join(" LIKE ? OR ")+" LIKE ?",
        search : Array(columns.length).fill('%'+search+'%')
      }
    },}
};

Folder customers kita anggap sebagai modul yang didalamnya terdapat folder beberapa folder MVC.

customer.model.js untuk merepresentasikan data customers di DB

const Customer = function(customer) {
  this.email = customer.email;
  this.name = customer.name;
  this.active = customer.active;
};Customer.table = "customers";module.exports = Customer;

customer.controller.js untuk melakukan logika dan mengontrol modul

const Customer = require("../models/customer.model.js");
const coreModel = require("../../../core/core.model.js")(Customer.table);// http://localhost:3000/customers?search=ayu&page=3&per_page=3
exports.getAll = (req, res) => {
  
  req.column = ["name", "email", "active"];coreModel.paginate(req, (err, data) => {
    if (err)
      res.status(500).send({
        message:
          err.message || "Some error occurred while retrieving customers."
      });
    else res.send(data);
  });
};exports.store = (req, res) => {
  if (!req.body) {
    res.status(400).send({
      message: "Content can not be empty!"
    });
  }
  // can custom object
  const customer = new Customer({
    email: req.body.email,
    name: req.body.name,
    active: req.body.active
  });coreModel.store(customer, (err, data) => {
    if (err)
      res.status(500).send({
        message:
          err.message || "Some error occurred while creating the Customer."
      });
    else res.send(data);
  });
};exports.show = (req, res) => {
  coreModel.show(req.params.customerId, (err, data) => {
    if (err) {
      if (err.kind === "not_found") {
        res.status(404).send({
          message: `Not found Customer with id ${req.params.customerId}.`
        });
      } else {
        res.status(500).send({
          message: "Error retrieving Customer with id " + req.params.customerId
        });
      }
    } else res.send(data);
  });
};exports.update = (req, res) => {
  if (!req.body) {
    res.status(400).send({
      message: "Content can not be empty!"
    });
  }coreModel.update(
    req.params.customerId,
    new Customer(req.body),
    (err, data) => {
      if (err) {
        if (err.kind === "not_found") {
          res.status(404).send({
            message: `Not found Customer with id ${req.params.customerId}.`
          });
        } else {
          res.status(500).send({
            message: "Error updating Customer with id " + req.params.customerId
          });
        }
      } else res.send(data);
    }
  );
};exports.destroy = (req, res) => {
  coreModel.destroy(req.params.customerId, (err, data) => {
    if (err) {
      if (err.kind === "not_found") {
        res.status(404).send({
          message: `Not found Customer with id ${req.params.customerId}.`
        });
      } else {
        res.status(500).send({
          message: "Could not delete Customer with id " + req.params.customerId
        });
      }
    } else res.send({ message: `Customer was deleted successfully!` });
  });
};

customer.router.js untuk mengontrol proses CRUD modul customers

const customers = require("../controllers/customer.controller.js");module.exports = app => {
    app.get("/customers", customers.getAll);
    app.post("/customers", customers.store);
    app.get("/customers/:customerId", customers.show);
    app.put("/customers/:customerId", customers.update);
    app.delete("/customers/:customerId", customers.destroy);
};

Silahkan coba dengan aplikasi postman dengan mengetik

node server

kemudian akses URL

http://localhost:3000/customers?search=ayu&page=1&per_page=2

hasilnya kurang lebih seperti ini

Hasil dari paginasi getAll Customer

Sekian, semoga bermanfaat 😄