mysql-await

MySQL Async/Await Wrapper v2.0

Simple wrapper for MySQL async/await functionality. Intended for functionality to mimic the popular mysql Node.js callback-based package, but with additional methods for awaiting execution. Goal is for normal methods to be unaffected and only additional await methods added, though accomplished through intermediary class objects.

Provided async/await methods

The methods below have been added as async/await wrappers to existing MySQL methods of similar name. In order to use them, simply "await" their execution rather than passing a callback for the last argument of the function call.

Connections from mysql.createConnect()

• Connection.awaitBeginTransaction()
• Connection.awaitChangeUser(params)
• Connection.awaitCommit()
• Connection.awaitConnect()
• Connection.awaitDestroy()
• Connection.awaitEnd()
• Connection.awaitQuery(query[, params])
• Connection.awaitRollback()

Connection Pool's from mysql.createPool()

• Pool.awaitEnd()
• Pool.awaitGetConnection()
• Pool.awaitQuery(query[, params])

Connections from pool.getConnection()

• Connection.awaitBeginTransaction()
• Connection.awaitChangeUser(params)
• Connection.awaitCommit()
• Connection.awaitQuery(query[, params])
• Connection.awaitRollback()

Configuration:

Example JSON configuration

{
  "connectionLimit" : 10,
  "host"            : "example.org",
  "user"            : "bob",
  "password"        : "secret",
  "database"        : "my_db"
}

Example JavaScript

const fs = require(`fs`);
const mysql = require(`./index`);

/** Self-executing asynchronous function so we can await results in this example */
(async () => {
  /** Create connection pool using loaded config */
  const pool = mysql.createPool(JSON.parse(fs.readFileSync(`mysql-config.json`)));

  pool.on(`acquire`, (connection) => {
    console.log(`Connection %d acquired`, connection.threadId);
  });
  
  pool.on(`connection`, (connection) => {
    console.log(`Connection %d connected`, connection.threadId);
  });

  pool.on(`enqueue`, () => {
    console.log(`Waiting for available connection slot`);
  });

  pool.on(`release`, function (connection) {
    console.log(`Connection %d released`, connection.threadId);
  });

  const connection = await pool.awaitGetConnection();
  
  connection.on(`error`, (err) => {
    console.error(`Connection error ${err.code}`);
  });

  /** Perform query on connection */
  let result = await connection.awaitQuery(`SELECT * FROM transactions WHERE ticker = ?`, [`DE`]);
  
  /** Log output */
  console.log(result);
  
  /** Release connection */
  connection.release();
    
  /** Perform query on pool (opens a connection, runs query, releases connection) */
  result = await pool.awaitQuery(`SELECT * FROM transactions WHERE ticker = ?`, [`KSS`]);
  
  /** Log output */
  console.log(result);
  
  /** Get a new connection from the pool */
  const connection2 = await pool.awaitGetConnection();
  
  /** Begin a new transaction */
  await connection2.awaitBeginTransaction();
  
  /** Perform query for max id number in users table */
  result = await connection2.awaitQuery(`SELECT MAX(id) maxId FROM users`);
  
  /** Add one to max id to get new id number */
  const newId = result[0].maxId + 1;
  
  /** Insert new test user with new id number */
  await connection2.awaitQuery(`INSERT INTO users (id, hash, username, name, accounts) VALUES (?, ?, ?, ?, ?)`, [newId, ``, `testuser`, `Test User`, ``]);
  
  /** Commit transaction */
  await connection2.awaitCommit();
  
  /** Release connection */
  connection2.release();
  
  /** Close connection pool */
  await pool.awaitEnd();
})();

Example Output

Connection 218 connected
Connection 218 acquired
[ RowDataPacket {
    id: 56,
    account: 3,
    commission: 7,
    date: 2018-05-17T07:00:00.000Z,
    price: 146.71,
    shares: 20,
    ticker: 'DE',
    type: 1 },
  RowDataPacket {
    id: 112,
    account: 3,
    commission: 7,
    date: 2018-05-21T07:00:00.000Z,
    price: 158.83,
    shares: -20,
    ticker: 'DE',
    type: 2 } ]
Connection 218 released
Connection 218 acquired
Connection 218 released
[ RowDataPacket {
    id: 17,
    account: 1,
    commission: 7,
    date: 2017-11-09T08:00:00.000Z,
    price: 38.23,
    shares: 100,
    ticker: 'KSS',
    type: 1 },
  RowDataPacket {
    id: 18,
    account: 1,
    commission: 7,
    date: 2017-11-10T08:00:00.000Z,
    price: 42.6,
    shares: -100,
    ticker: 'KSS',
    type: 2 } ]
Connection 218 acquired
Connection 218 released

Not Currently Supported

• Pool Cluster's -- for now, can be added later if needed
• Result streams -- for now, can be added later if needed

Contributing

• Please open issue for any bugs found or feature requests

License

MIT