ntxJYQVv

1const db = require('sqlite3');
2
3const Logger = require('../logger/logger');
4
5const dataDir = process.env.DATA_DIR;
6const dbExt = process.env.DB_EXT;
7
8const DataManager = {
9  /**
10   * Constructor for OLOO style behavior delgation.
11   * @param {string} dbFile - data base file name
12   */
13  init: function (dbFile) {
14    if (!dbFile || !dataDir || !dbExt) {
15      Logger.error('Database or exchange is undefined');
16    } else {
17      this.dbFile = dbFile;
18    }
19
20    Logger.info('Data manager initialized.');
21  },
22
23    /**
24   * Returns a live sqlite connection
25   */
26  getDb: function () {
27    const dbConn = new db.Database(`${dataDir}${this.dbFile}${dbExt}`);
28    return dbConn;
29  },
30
31   /**
32   * Stores a batch of trades in the sqlite db
33   * @param {array} batch - batch of trades
34   */
35  storeTrades: async function (batch) {
36    try {
37      return new Promise(resolve => {
38        if (!this.dbFile) {
39          throw('Database file unspecified');
40        }
41
42        if (!batch || !batch.length) {
43          throw('Data must be specified and an array');
44        }
45
46        const dbConn = this.getDb();
47        const table = `[${batch[0].symbol}]`;
48        const query = `CREATE TABLE IF NOT EXISTS ${table} (id INTEGER PRIMARY KEY AUTOINCREMENT, tradeId INTEGER, timestamp INTEGER, price REAL, quantity REAL)`;
49        dbConn.serialize(() => {
50          dbConn.run(query);
51          dbConn.run('BEGIN TRANSACTION');
52          const insertStmt = dbConn.prepare(`INSERT INTO ${table} (tradeId, timestamp, price, quantity) VALUES (?, ?, ?, ?)`);
53          batch.forEach(trade => insertStmt.run(trade.id, trade.timestamp, trade.info.p, trade.info.q));
54          insertStmt.finalize();
55          dbConn.run('COMMIT');
56        });
57
58        dbConn.close(resolve);
59        Logger.debug(`${batch.length} rows inserted into table`);
60      });
61    } catch (e) {
62      Logger.error(e.message);
63    }
64  }
65};