云函数serverless DB node SDK

概述

用于简化用户使用云函数时候连接DB和管理链接池的操作，利用云函数的的特性，提供便捷高效又接近mysql库的操作封装接口

用法

/*
环境变量(示例)：
process.env['DB_TESTDB2_HOST'] = 192.168.1.1
process.env['DB_TESTDB2_PORT'] = 3306
process.env['DB_TESTDB2_USER'] = ycp424c
process.env['DB_TESTDB2_PASSWORD'] = pwd123321123
process.env['DB_TESTDB2_DATABASE'] = db_name
process.env['DB_TESTDB2_CONNECTION_LIMIT'] = 2 //链接池的最大链接数，默认5
*/

const database = require('scf-nodejs-serverlessdb-sdk').database

exports.main_handler = async (event, context) => {
  //use connection
  const connection = await database('TESTDB2').connection()
  const result = await connection.queryAsync('select * from coffee')
  connection.release() //must release before return
  console.log('db2 query result:',result)

  //use pool
  //如果使用pool会使用连接池，函数跟DB会维持一个长连接，在Node10+的runtime中需要关掉等待异步的机制
  context.callbackWaitsForEmptyEventLoop = false
  const pool = await database('TESTDB2').pool()
  const result2 = await pool.queryAsync('select * from coffee')
  // no need to release pool

  console.log('db2 query result:',result2)
}