Kf4GDhqH

1import mysql from 'mysql';
2import user  from './user';
3import post  from './post';
4
5class db {
6    constructor() {
7	// init db
8	this.init();
9
10	// init connect pool
11    	this.pool  = mysql.createPool({
12    	    connectionLimit : 10,
13    	    host            : 'localhost',
14    	    user            : 'root',
15    	    password        : 'password',
16    	    database        : 'rss'
17    	});
18
19	// init tables
20	this.initTables();
21    }
22
23    init () {
24	// create db if not exist
25	const connection = mysql.createConnection({
26    	    host            : 'localhost',
27    	    user            : 'root',
28    	    password        : 'password',
29	});
30
31	connection.connect((err) => {
32	    connection.query('CREATE DATABASE IF NOT EXISTS rss',);
33	    connection.end();
34	});
35    }
36
37    initTables () {
38	// user table
39	this.query(user.schema());
40	this.query(user.subscriberMapping());
41	this.query(user.postsMapping());
42
43	// post table
44	this.query(post.schema());
45    }
46
47    query(sql, cb) {
48	this.pool.getConnection((err, connection) => {
49	    console.log(sql);
50
51	    if (err) return console.log('error: ' + err.message);
52
53	    connection.query(sql, (error, results, fields) => {
54		if (null != cb) cb(results);
55		connection.release();
56
57		if (error) return console.log('error: ' + error.message);
58	    });
59	});
60    }
61
62    shutdown() {
63	this.pool.end((err) => {
64	    console.log('Error occured when shutting down db: ' + err);
65	});
66    }
67
68    static instance() {
69	if (null == db._instance) {
70	    db._instance = new db();
71	}
72	return db._instance;
73    }
74}
75db._instance = null;
76
77export default db;