Create initial MySql helper class

Currently only creates and closes connections.

app.js

@@ -2,8 +2,12 @@
  * NodeJS application to connect to MySQL and make database queries.
  */
 
+// System Imports.
+// const mysql = require('mysql2');
+
 // User Imports.
-import config from './src/config.js';
+const config = require('./src/config.js');
+const MySql = require('./src/mysql.js');
 
 
 /**
@@ -13,7 +17,12 @@ function main() {
     console.log('Starting program.');
     console.log('');
 
-    console.log(config['mysql']);
+    var debug = true;
+
+    // Create MySql helper class.
+    const mysql = new MySql(config['mysql'], debug);
+    mysql.open_conn();
+    mysql.close_conn();
 
     console.log('');
     console.log('Terminating program.');

package.json

@@ -6,5 +6,7 @@
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1"
   },
-  "type": "module"
+  "dependencies": {
+    "mysql2": "^2.1.0"
+  }
 }

src/config.js

@@ -5,12 +5,13 @@
 
 var config = {
     mysql: {
-        user: 'root',
-        password: 'root',
-        database: 'js_test',
         host: '127.0.0.1',
-        port: '3306'
+        port: '3306',
+        database: 'mysql_bot_example',
+        user: 'root',
+        password: 'root'
     }
 }
 
-export default config;
+
+module.exports = config;

src/mysql.js

+/**
+ * Helper class to handle MySql logic.
+ */
+
+// System Imports.
+const mysql = require('mysql2');
+
+
+class MySql {
+
+    /**
+     * Class constructor.
+     */
+    constructor(config, debug) {
+        if (debug) {
+            console.log('Starting MySql helper class.');
+        }
+
+        // Save class variables.
+        this.config = config;
+        this.debug = debug;
+        this.connection = null;
+    }
+
+    /**
+     * Creates and returns a MySql connection object, using provided config values.
+     */
+    open_conn() {
+        if (this.debug) {
+            console.log('Creating MySql connection...');
+        }
+
+        // Check if connection is currently open.
+        if (this.connection != null) {
+            // Connection currently exists. Close so we can start a new one.
+            console.log('Connection already exist. Closing old connection first.');
+            this.close_conn();
+        }
+
+        // Open MySQL connection.
+        const connection = mysql.createConnection({
+            host: this.config['host'],
+            port: this.config['port'],
+            database: this.config['database'],
+            user: this.config['user'],
+            password: this.config['password']
+        });
+        console.log('Connection has been created.');
+
+        // Save connection to class.
+        this.connection =connection;
+
+        return connection;
+    }
+
+    /**
+     * Closes current MySql connection.
+     */
+    close_conn() {
+        if (this.debug) {
+            console.log('Closing MySql connection...');
+        }
+
+        // Check if connection is currently open.
+        if (this.connection != null) {
+            // Connection currently exists. Safe to close.
+            this.connection.end();
+            console.log('Connection has been terminated.');
+        } else {
+            // Connection does not yet exist. Cannot close.
+            console.log('There is no connection to close.');
+        }
+    }
+}
+
+
+module.exports = MySql;