Calculation/db_script/baseUtils.js

'use strict';


const fs = require('fs');
const path = require('path');
var util = require('util');
var logPath = path.join(`${process.argv[1]}.log`);
var logFile = fs.createWriteStream(logPath, { flags: 'a' });
console.log = function() {
    logFile.write(util.format.apply(null, arguments) + '\n');
    process.stdout.write(util.format.apply(null, arguments) + '\n');
};

const mysql = require('mysql');
const config = process.argv[2];
if (['local', 'uat', 'default'].indexOf(config) < 0) throw `参数错误: ${config}`;
const options = require(`../config/config.${config}`)({ baseDir: __dirname + '/app', root: __dirname, name: 'calc' });
const pool = mysql.createPool(options.mysql.client);
const querySql = async function(sql, sqlParam) {
    return new Promise(function(resolve, reject) {
        pool.getConnection(function(err, conn) {
            if (err) {
                if (err) console.log(err);
                reject(err);
            } else {
                conn.query(sql, sqlParam, function(err, rows, fields) {
                    if (err) console.log(err);
                    // 释放连接
                    conn.release();
                    // 传递Promise回调对象
                    resolve(rows);
                });
            }
        });
    });
};

const timesLen = 100;
const filterLastestData = function (data, keyFields, timesField = 'times', orderField = 'order') {
    const dataIndex = {};
    for (const d of data) {
        let key = 'd';
        for (const kf of keyFields) {
            key = key + '.' + (d[kf] || '');
        }

        const di = dataIndex[key];
        if (di) {
            if ((di[timesField] * timesLen + di[orderField]) < (d[timesField] * timesLen + d[orderField])) dataIndex[key] = d;
        } else {
            dataIndex[key] = d;
        }
    }
    const result = [];
    for (const prop in dataIndex) {
        result.push(dataIndex[prop]);
    }
    return result;
};

const zeroRange = 0.0000000001;
const bc = require('../app/lib/base_calc.js');
const Decimal = require('decimal.js');
Decimal.set({ precision: 50, defaults: true });

const ZhCalc = {
    // 加减乘除方法，为方便调用，兼容num为空的情况
    // 加减法使用base_calc，乘除法使用Decimal（原因详见demo/calc_test）
    /**
     * 加法 num1 + num2
     * @param num1
     * @param num2
     * @return {number}
     */
    add(num1, num2) {
        return bc.add(num1 ? num1 : 0, num2 ? num2 : 0);
    },
    /**
     * 减法 num1 - num2
     * @param num1
     * @param num2
     * @return {number}
     */
    sub(num1, num2) {
        return bc.sub(num1 ? num1 : 0, num2 ? num2 : 0);
    },
    /**
     * 乘法 num1 * num2
     * @param num1
     * @param num2
     * @return {*}
     */
    mul(num1, num2, digit = 6) {
        if (num1 === '' || num1 === null || num2 === '' || num2 === null) {
            return 0;
        }
        return Decimal.mul(num1 ? num1 : 0, num2 ? num2 : 0).toDecimalPlaces(digit).toNumber();
    },
    /**
     * 除法 num1 / num2
     * @param num1 - 被除数
     * @param num2 - 除数
     * @return {*}
     */
    div(num1, num2, digit = 6) {
        if (num2 && !this.checkZero(num2)) {
            return Decimal.div(num1 ? num1 : 0, num2).toDecimalPlaces(digit).toNumber();
        }
        return null;

    },
    /**
     * 四舍五入(统一，方便以后万一需要置换)
     * @param {Number} value - 舍入的数字
     * @param {Number} decimal - 要保留的小数位数
     * @return {*}
     */
    round(value, decimal) {
        return value ? new Decimal(value.toString()).toDecimalPlaces(decimal).toNumber() : 0;
    },
    /**
     * 汇总
     * @param array
     * @return {number}
     */
    sum(array) {
        let result = 0;
        for (const a of array) {
            result = this.add(result, a);
        }
        return result;
    },
    /**
     * 检查数字是否为0
     * @param {Number} value
     * @return {boolean}
     */
    checkZero(value) {
        return value === undefined || value === null || (this._.isNumber(value) && Math.abs(value) < zeroRange);
    },
    /**
     * 检查数字是否相等
     * @param {Number} value1
     * @param {Number} value2
     * @return {boolean}
     */
    numEqual(value1, value2) {
        if (value1 && value2) {
            return Math.abs(value2 - value1) < zeroRange;
        }
        return (!value1 && !value2);

    },
};

module.exports = {
    querySql,
    filterLastestData,
    closePool: function () {
        pool.end();
    },
    ZhCalc,
};