gateway-module/lib/index.js

for GW ,one of node-red module

const dbconfig={
    user : process.env.DB_USER || '',
    password : process.env.DB_PASS || '',
    server : process.env.DB_HOST || '',
    database : process.env.DB_NAME || '',
    port : parseInt(process.env.DB_PORT) || 1433,
    showSql : process.env.SHOW_SQL || false,
}
const mssql = require('littlemssql');
const mssqlConn = mssql(dbconfig);
const isMockData = process.env.ENABLE_MockData=='true'?true:false ;
// const fs =require('fs');
//定义一个缓存，用来对比数据值判断
function cacheHandle() {
    //默认预设metric计数缓存对象
    const cache = new Map();
    const metric = {
        total: 0,
        filter: 0
    };
    cache.set('metric', metric);
    return cache;
}

async function getDevicesByType(cache,...deviceTypeIds) {
    let result;
    if (isMockData === true) {
        result = require('../config/mockData.json');
    }else{
        result = await mssqlConn.queryData(`
            select point.deviceId, point.monitor, point.monitorTypeId, point.isNumber, info.deviceTypeId, info.deviceNo, info.tenantId
            from ts_deviceInfo as info INNER JOIN ts_devicepoint as point
            on info.deviceId=point.deviceId
            where info.deviceTypeId in (${deviceTypeIds.join()})
        `);
        result = result.recordset;
    }
    //缓存设备数据
    // fs.writeFileSync('./config/mockData.json',JSON.stringify(result),{encoding:'utf-8'});
    for (const device of result) {
        if (cache.has(device.deviceNo)) {
            cache.get(device.deviceNo).push(device);
        }else{
            cache.set(device.deviceNo,new Array(device));
        }
    }
    console.log("cache done");
}


module.exports = {
    config: {
         sendTopic : process.env.WALLE_FILTERED_TOPIC || 'gate',
         deviceTypeIds : process.env.CACHE_DEVICETYP
    },
    cache: cacheHandle,
    data: getDevicesByType
};