diff options
Diffstat (limited to 'node_modules/mysql2/lib/pool.js')
-rw-r--r-- | node_modules/mysql2/lib/pool.js | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/node_modules/mysql2/lib/pool.js b/node_modules/mysql2/lib/pool.js new file mode 100644 index 0000000..2ad4998 --- /dev/null +++ b/node_modules/mysql2/lib/pool.js @@ -0,0 +1,212 @@ +'use strict'; + +const process = require('process'); +const mysql = require('../index.js'); + +const EventEmitter = require('events').EventEmitter; +const PoolConnection = require('./pool_connection.js'); +const Queue = require('denque'); +const Connection = require('./connection.js'); + +function spliceConnection(queue, connection) { + const len = queue.length; + for (let i = 0; i < len; i++) { + if (queue.get(i) === connection) { + queue.removeOne(i); + break; + } + } +} + +class Pool extends EventEmitter { + constructor(options) { + super(); + this.config = options.config; + this.config.connectionConfig.pool = this; + this._allConnections = new Queue(); + this._freeConnections = new Queue(); + this._connectionQueue = new Queue(); + this._closed = false; + } + + promise(promiseImpl) { + const PromisePool = require('../promise').PromisePool; + return new PromisePool(this, promiseImpl); + } + + getConnection(cb) { + if (this._closed) { + return process.nextTick(() => cb(new Error('Pool is closed.'))); + } + let connection; + if (this._freeConnections.length > 0) { + connection = this._freeConnections.shift(); + this.emit('acquire', connection); + return process.nextTick(() => cb(null, connection)); + } + if ( + this.config.connectionLimit === 0 || + this._allConnections.length < this.config.connectionLimit + ) { + connection = new PoolConnection(this, { + config: this.config.connectionConfig + }); + this._allConnections.push(connection); + return connection.connect(err => { + if (this._closed) { + return cb(new Error('Pool is closed.')); + } + if (err) { + return cb(err); + } + this.emit('connection', connection); + this.emit('acquire', connection); + return cb(null, connection); + }); + } + if (!this.config.waitForConnections) { + return process.nextTick(() => cb(new Error('No connections available.'))); + } + if ( + this.config.queueLimit && + this._connectionQueue.length >= this.config.queueLimit + ) { + return cb(new Error('Queue limit reached.')); + } + this.emit('enqueue'); + return this._connectionQueue.push(cb); + } + + releaseConnection(connection) { + let cb; + if (!connection._pool) { + // The connection has been removed from the pool and is no longer good. + if (this._connectionQueue.length) { + cb = this._connectionQueue.shift(); + process.nextTick(this.getConnection.bind(this, cb)); + } + } else if (this._connectionQueue.length) { + cb = this._connectionQueue.shift(); + process.nextTick(cb.bind(null, null, connection)); + } else { + this._freeConnections.push(connection); + this.emit('release', connection); + } + } + + end(cb) { + this._closed = true; + if (typeof cb !== 'function') { + cb = function(err) { + if (err) { + throw err; + } + }; + } + let calledBack = false; + let closedConnections = 0; + let connection; + const endCB = function(err) { + if (calledBack) { + return; + } + if (err || ++closedConnections >= this._allConnections.length) { + calledBack = true; + cb(err); + return; + } + }.bind(this); + if (this._allConnections.length === 0) { + endCB(); + return; + } + for (let i = 0; i < this._allConnections.length; i++) { + connection = this._allConnections.get(i); + connection._realEnd(endCB); + } + } + + query(sql, values, cb) { + const cmdQuery = Connection.createQuery( + sql, + values, + cb, + this.config.connectionConfig + ); + if (typeof cmdQuery.namedPlaceholders === 'undefined') { + cmdQuery.namedPlaceholders = this.config.connectionConfig.namedPlaceholders; + } + this.getConnection((err, conn) => { + if (err) { + if (typeof cmdQuery.onResult === 'function') { + cmdQuery.onResult(err); + } else { + cmdQuery.emit('error', err); + } + return; + } + try { + conn.query(cmdQuery).once('end', () => { + conn.release(); + }); + } catch (e) { + conn.release(); + throw e; + } + }); + return cmdQuery; + } + + execute(sql, values, cb) { + // TODO construct execute command first here and pass it to connection.execute + // so that polymorphic arguments logic is there in one place + if (typeof values === 'function') { + cb = values; + values = []; + } + this.getConnection((err, conn) => { + if (err) { + return cb(err); + } + try { + conn.execute(sql, values, cb).once('end', () => { + conn.release(); + }); + } catch (e) { + conn.release(); + throw e; + } + }); + } + + _removeConnection(connection) { + // Remove connection from all connections + spliceConnection(this._allConnections, connection); + // Remove connection from free connections + spliceConnection(this._freeConnections, connection); + this.releaseConnection(connection); + } + + format(sql, values) { + return mysql.format( + sql, + values, + this.config.connectionConfig.stringifyObjects, + this.config.connectionConfig.timezone + ); + } + + escape(value) { + return mysql.escape( + value, + this.config.connectionConfig.stringifyObjects, + this.config.connectionConfig.timezone + ); + } + + escapeId(value) { + return mysql.escapeId(value, false); + } +} + +module.exports = Pool; |