lib/dialects/mysql/runner.js

MySQL Runner

module.exports = function(client) { var _ = require('lodash'); var inherits = require('inherits'); var Promise = require('../../promise'); var Runner = require('../../runner'); var helpers = require('../../helpers');

Inherit from the Runner constructor's prototype, so we can add the correct then method.

function Runner_MySQL() { this.client = client; Runner.apply(this, arguments); } inherits(Runner_MySQL, Runner);

Grab a connection, run the query via the MySQL streaming interface, and pass that through to the stream we've sent back to the client.

Runner_MySQL.prototype._stream = Promise.method(function(sql, stream, options) { var runner = this; return new Promise(function(resolver, rejecter) { stream.on('error', rejecter); stream.on('end', resolver); runner.connection.query(sql.sql, sql.bindings).stream(options).pipe(stream); }); });

Runs the query on the specified connection, providing the bindings and any other necessary prep work.

Runner_MySQL.prototype._query = Promise.method(function(obj) { var sql = obj.sql; if (this.isDebugging()) this.debug(obj); if (obj.options) sql = _.extend({sql: sql}, obj.options); var connection = this.connection; if (!sql) throw new Error('The query is empty'); return new Promise(function(resolver, rejecter) { connection.query(sql, obj.bindings, function(err, rows, fields) { if (err) return rejecter(err); obj.response = [rows, fields]; resolver(obj); }); }); });

Process the response as returned from the query.

Runner_MySQL.prototype.processResponse = function(obj) { var response = obj.response; var method = obj.method; var rows = response[0]; var fields = response[1]; var resp; if (obj.output) { return obj.output.call(this, rows, fields); } else if (method === 'select') { resp = helpers.skim(rows); } else if (method === 'insert') { resp = [rows.insertId]; } else if (method === 'del' || method === 'update') { resp = rows.affectedRows; } else { resp = response; } return resp; };

Assign the newly extended Runner constructor to the client object.

client.Runner = Runner_MySQL; };