Node.js

const express = require('express');
const bodyParser = require('body-parser');
const path = require('path');
const Promise = require('bluebird');
require('date-format-lite');

const port = 1337;
const app = express();
const mysql = require('promise-mysql');

app.use(express.static(path.join(__dirname, 'public')));
app.use(bodyParser.urlencoded({ extended: true }));

app.listen(port, () => {
  console.log('Server is running on port ' + port + '...');
});
async function serverConfig() {
  const db = await mysql.createPool({
    host: 'localhost',
    user: 'root',
    password: '',
    database: 'gantt-howto-node',
  });
  app.get('/data', (req, res) => {
    Promise.all([db.query('SELECT * FROM gantt_tasks'), db.query('SELECT * FROM gantt_links')])
      .then((results) => {
        let tasks = results[0],
          links = results[1];

        for (let i = 0; i < tasks.length; i++) {
          tasks[i].start_date = tasks[i].start_date.format('YYYY-MM-DD hh:mm:ss');
        }

        res.send({
          data: tasks,
          collections: { links },
        });
      })
      .catch((error) => {
        sendResponse(res, 'error', null, error);
      });
  });

  // add new task
  app.post('/data/task', (req, res) => {
    // adds new task to database
    let task = getTask(req.body);
    const { text, start_date, duration, progress, parent } = task;

    db.query('SELECT MAX(sortorder) AS maxOrder FROM gantt_tasks')
      .then((result) => {
        /*!*/ // assign max sort order to new task
        let orderIndex = (result[0].maxOrder || 0) + 1;
        return db.query(
          'INSERT INTO gantt_tasks(text, start_date, duration, progress, parent, sortorder) VALUES (?,?,?,?,?,?)',
          [text, start_date, duration, progress, parent, orderIndex]
        );
      })
      .then((result) => {
        sendResponse(res, 'inserted', result.insertId);
      })
      .catch((error) => {
        sendResponse(res, 'error', null, error);
      });
  });

  // update task
  app.put('/data/task/:id', (req, res) => {
    let sid = req.params.id,
      target = req.body.target,
      task = getTask(req.body);
    const { text, start_date, duration, progress, parent } = task;

    Promise.all([
      db.query('UPDATE gantt_tasks SET text = ?, start_date = ?, duration = ?, progress = ?, parent = ? WHERE id = ?', [
        text,
        start_date,
        duration,
        progress,
        parent,
        sid,
      ]),
      updateOrder(sid, target),
    ])
      .then((result) => {
        sendResponse(res, 'updated');
      })
      .catch((error) => {
        sendResponse(res, 'error', null, error);
      });
  });

  function updateOrder(taskId, target) {
    let nextTask = false;
    let targetOrder;

    target = target || '';

    if (target.startsWith('next:')) {
      target = target.substr('next:'.length);
      nextTask = true;
    }

    return db.query('SELECT * FROM gantt_tasks WHERE id = ?', [target]).then((result) => {
      if (!result[0]) return Promise.resolve();

      targetOrder = result[0].sortorder;
      if (nextTask) targetOrder++;

      return db
        .query('UPDATE gantt_tasks SET sortorder = sortorder + 1 WHERE sortorder >= ?', [targetOrder])
        .then((result) => {
          return db.query('UPDATE gantt_tasks SET sortorder = ? WHERE id = ?', [targetOrder, taskId]);
        });
    });
  }

  // delete task
  app.delete('/data/task/:id', (req, res) => {
    let sid = req.params.id;
    db.query('DELETE FROM gantt_tasks WHERE id = ?', [sid])
      .then((result) => {
        sendResponse(res, 'deleted');
      })
      .catch((error) => {
        sendResponse(res, 'error', null, error);
      });
  });

  // add link
  app.post('/data/link', (req, res) => {
    let link = getLink(req.body);
    const { source, target, type } = link;

    db.query('INSERT INTO gantt_links(source, target, type) VALUES (?,?,?)', [source, target, type])
      .then((result) => {
        sendResponse(res, 'inserted', result.insertId);
      })
      .catch((error) => {
        sendResponse(res, 'error', null, error);
      });
  });

  // update link
  app.put('/data/link/:id', (req, res) => {
    let sid = req.params.id,
      link = getLink(req.body);
    const { source, target, type } = link;

    db.query('UPDATE gantt_links SET source = ?, target = ?, type = ? WHERE id = ?', [source, target, type, sid])
      .then((result) => {
        sendResponse(res, 'updated');
      })
      .catch((error) => {
        sendResponse(res, 'error', null, error);
      });
  });

  // delete link
  app.delete('/data/link/:id', (req, res) => {
    let sid = req.params.id;
    db.query('DELETE FROM gantt_links WHERE id = ?', [sid])
      .then((result) => {
        sendResponse(res, 'deleted');
      })
      .catch((error) => {
        sendResponse(res, 'error', null, error);
      });
  });

  function getTask(data) {
    return {
      text: data.text,
      start_date: data.start_date.date('YYYY-MM-DD'),
      duration: data.duration,
      progress: data.progress || 0,
      parent: data.parent,
    };
  }

  function getLink(data) {
    return {
      source: data.source,
      target: data.target,
      type: data.type,
    };
  }

  function sendResponse(res, action, tid, error) {
    if (action == 'error') console.log(error);

    let result = {
      action: action,
    };
    if (tid !== undefined && tid !== null) result.tid = tid;

    res.send(result);
  }
}
serverConfig();