依赖模块:
1. mysql:https://github.com/felixge/node-mysql
npm install mysql --save
2. async:https://github.com/caolan/async
npm install async --save
(ps: async模块可换成其它Promise模块如bluebird、q等)
因为Node.js的mysql模块本身对于事务的封装过于简单,而且直接使用会有很严重callback hell,故我们封装了两个方法,一个用来初始化sql & params,一个用来执行事务。
初始化sql & params:
function _getNewSqlParamEntity(sql, params, callback) { if (callback) { return callback(null, { sql: sql, params: params }); } return { sql: sql, params: params }; }
如果你要执行多条sql语句,则需要:
var sqlParamsEntity = []; var sql1 = "insert table set a=?, b=? where 1=1"; var param1 = {a:1, b:2}; sqlParamsEntity.push(_getNewSqlParamEntity(sql1, param1)); var sql2 = "update ..."; sqlParamsEntity.push(_getNewSqlParamEntity(sql1, [])); //...更多要事务执行的sql
然后我在我自己的dbHelper.js里封装了execTrans的函数,用来执行事务
var mysql = require('mysql'); var async = require("async"); module.exports = { execTrans: execTrans, } var pool = mysql.createPool({ host: "mysql host", user: "mysql login user", password: "mysql login pwd", database: "target db name", connectionLimit: 10, port: "mysql db port", waitForConnections: false }); function execTrans(sqlparamsEntities, callback) { pool.getConnection(function (err, connection) { if (err) { return callback(err, null); } connection.beginTransaction(function (err) { if (err) { return callback(err, null); } console.log("开始执行transaction,共执行" + sqlparamsEntities.length + "条数据"); var funcAry = []; sqlparamsEntities.forEach(function (sql_param) { var temp = function (cb) { var sql = sql_param.sql; var param = sql_param.params; connection.query(sql, param, function (tErr, rows, fields) { if (tErr) { connection.rollback(function () { console.log("事务失败," + sql_param + ",ERROR:" + tErr); throw tErr; }); } else { return cb(null, 'ok'); } }) }; funcAry.push(temp); }); async.series(funcAry, function (err, result) { console.log("transaction error: " + err); if (err) { connection.rollback(function (err) { console.log("transaction error: " + err); connection.release(); return callback(err, null); }); } else { connection.commit(function (err, info) { console.log("transaction info: " + JSON.stringify(info)); if (err) { console.log("执行事务失败," + err); connection.rollback(function (err) { console.log("transaction error: " + err); connection.release(); return callback(err, null); }); } else { connection.release(); return callback(null, info); } }) } }) }); }); }
这样就可以执行事务了:
execTrans(sqlParamsEntity, function(err, info){ if(err){ console.error("事务执行失败"); }else{ console.log("done."); } })
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持毛票票。