mysql-endpoint-express/index.js

MySQL Connection on Express JS (Api Endpoint)

require('dotenv').config();
const express = require('express');
const mysql = require('mysql');
const app = express();
app.use(express.json());

const connection = mysql.createConnection({
  host: process.env.DB_HOST,
  user: process.env.DB_USER,
  password: process.env.DB_PASSWORD,
  database: process.env.DB_DATABASE
});
connection.connect();

app.use((req, res, next) => {
  const allowedOrigin = process.env.ALLOWED_ORIGIN;
  const allowedMethods = process.env.ALLOWED_METHODS;
  const allowedHeaders = process.env.ALLOWED_HEADERS;
  res.setHeader('Access-Control-Allow-Origin', allowedOrigin);
  res.setHeader('Access-Control-Allow-Methods', allowedMethods);
  res.setHeader('Access-Control-Allow-Headers', allowedHeaders);
  next();
});

const checkRole = (allowedRoles) => {
  return (req, res, next) => {
    const role = req.headers.role;
    if (allowedRoles.includes(role) || !role) {
      next();
    } else {
      res.status(403).send('Forbidden');
    }
  };
};

app.get('/api', checkRole([process.env.PREFIX_ROLE]), (req, res) => {
  connection.query('SHOW TABLES', (error, tables) => {
    if (error) throw error;
    const tableNames = tables.map(table => table[`Tables_in_${connection.config.database}`]);
    const data = {};
    tableNames.forEach(table => {
      connection.query(`SELECT * FROM ${table}`, (error, results) => {
        if (error) throw error;
        data[table] = results;
        if (Object.keys(data).length === tableNames.length) {
          res.json(data);
        }
      });
    });
  });
});

app.get('/api/:table', checkRole([process.env.PREFIX_ROLE]), (req, res) => {
  const { table } = req.params;
  connection.query(`SELECT * FROM ${table}`, (error, results) => {
    if (error) {
      res.status(500).send('Error retrieving data from database');
    } else {
      res.status(200).json(results);
    }
  });
});

app.post('/api/:table', checkRole([process.env.PREFIX_ROLE]), (req, res) => {
  const { table } = req.params;
  const data = req.body;

  connection.query(`INSERT INTO ${table} SET ?`, data, (error, results) => {
    if (error) {
      res.status(500).send('Error creating data in database');
    } else {
      res.status(201).send('Data created successfully');
    }
  });
});

app.put('/api/:table/:id', checkRole([process.env.PREFIX_ROLE]), (req, res) => {
  const { table, id } = req.params;
  const data = req.body;
  connection.query(`SHOW KEYS FROM ${table} WHERE Key_name = 'PRIMARY'`, (error, results) => {
    if (error) {
      console.log(error);
      res.status(500).send('Error retrieving primary key information');
    } else {
      if (results.length > 0) {
        const primaryKeyColumn = results[0].Column_name;
        connection.query(`UPDATE ${table} SET ? WHERE ${primaryKeyColumn} = ?`, [data, id], (error, results) => {
          if (error) {
            console.log(error);
            res.status(500).send('Error updating data in database');
          } else {
            res.status(200).send('Data updated successfully');
          }
        });
      } else {
        res.status(404).send('Primary key not found in table');
      }
    }
  });
});

app.delete('/api/:table/:id', checkRole([process.env.PREFIX_ROLE]), (req, res) => {
  const { table, id } = req.params;
  connection.query(`SHOW KEYS FROM ${table} WHERE Key_name = 'PRIMARY'`, (error, results) => {
    if (error) {
      console.log(error);
      res.status(500).send('Error retrieving primary key information');
    } else {
      if (results.length > 0) {
        const primaryKeyColumn = results[0].Column_name;
        connection.query(`DELETE FROM ${table} WHERE ${primaryKeyColumn} = ?`, [id], (error, deleteResult) => {
          if (error) {
            console.log(error);
            res.status(500).send('Error deleting data from database');
          } else {
            res.status(200).send('Data deleted successfully');
          }
        });
      } else {
        res.status(404).send('Primary key not found in table');
      }
    }
  });
});

app.get('/', (req, res) => {
  res.status(200).send('Server Running, Go ../api');
});

app.get('*', (req, res) => {
  res.status(404).send('Data not found');
});

app.listen(process.env.DB_PORT, () => {
  console.log('Server is running on port ' + process.env.DB_PORT);
});

module.exports = app;