ConstructionCost/public/counter/counter.js

/**
 * Created by Tony on 2017/3/21.
 */
var mongoose = require('mongoose');
var dbm = require("../../config/db/db_manager");
var projectdb = dbm.getCfgConnection("scConstruct");

var Schema = mongoose.Schema;
var counterSchema = new Schema({
    _id: String,
    sequence_value: Number
});
counterSchema.statics.findAndModify = function (query, sort, doc, options, callback) {
    return this.collection.findAndModify(query, sort, doc, options, callback);
};
var counterModel = projectdb.model("counters", counterSchema);

// All counter Must predefine in DB
const COUNTER_MODULE_NAME = {
    project: 'projects',
    user: 'users',
    bills: 'bills',
    ration: 'rations',
    report: 'rptTemplates',
    fee: 'fees',
    template_bills: 'temp_bills'
}
/*const PROJECT_COUNTER = 'projects', USER_COUNTER = 'users', BILL_COUNTER = 'bills', RATION_COUNTER = 'rations',
    REPORT_COUNTER = 'rptTemplates', FEE_COUNTER = 'fees'*/

var counterDAO = function(){};

/*
 * callback = function (err, result) {
 *     result.value.sequence_value ΪÐ޸ĺóµÄid
 * }
 */
counterDAO.prototype.getIDAfterCount = function(moduleName, stepCount, callback) {
    var sc = stepCount;
    if (isNaN(stepCount) || (stepCount < 0)) {
        sc = 1;
    } else if (!(/^-?\d+$/.test(stepCount))) {
        sc = Math.round(stepCount + 0.5);
    }
    counterModel.findAndModify({_id: moduleName}, [], { $inc: { sequence_value: sc } }, {'new':true}, callback);
}

counterDAO.prototype.getCurrentID = function(moduleName, callback) {
    if (callback) {
        counterModel.findOne({_id: moduleName}).exec()
        .then(function(result, err) {
            if (callback) {
                callback(result, err);
            }
        }
        );
        return null;
    } else {
        var rst = counterModel.findOne({_id: moduleName}).exec() ;
        return rst;
    }
}

module.exports = {
    counterDAO: new counterDAO(),
    moduleName: COUNTER_MODULE_NAME
};