pivot_forecast/index.js

#!/usr/bin/env node

require('dotenv').config();
const express = require('express');
//var https = require('https');
var bodyParser = require('body-parser');
const server = express();
const pg = require('pg');
var fs = require('fs');
var readline = require('readline');

//-----------------------------point to ssl info------------------------------------
//var options = {
//    key: fs.readFileSync(process.env.wd + 'key.pem'),
//    cert: fs.readFileSync(process.env.wd + 'cert.pem'),
//    passprase: []
//};

//-----------------------------create server process--------------------------------
//https.createServer( /*options,*/ server).listen(process.env.nodeport, () => {
server.listen(process.env.nodeport, () => {
    console.log('started on ' + process.env.nodeport)
});

//-----------------------------create permanent database connetion------------------
var Postgres = new pg.Client({
    user: process.env.user,
    password: process.env.password,
    host: process.env.host,
    port: process.env.port,
    database: process.env.database,
    ssl: false,
    application_name: "ps_api"
});
Postgres.connect();


const SQLTemplate = (inSql, inJSON) => {
    for (key in inJSON) {
        inSql = inSql.replace(new RegExp(key, 'g'), inJSON[key]);
    }
    return inSql;
};
const build_where = (req, c, w) => {
    //loop through each top level item expected to be a simple key/value list reflecting the column and the target value
    // "part":"XFRM500", "customer":"Sanford and Son" --> SQL -->     part = 'XFRM500'
    //                                                            AND customer = 'Sanford and Son'
    var d = 1;
    var args = [];

    for (var i in req.body.app_scenario) {
        //console.log(i);
        ///console.log(req.body[i]);
        //this step applies the AND seperator only
        if (c > 1) {
            w = w +
                `
    AND `;
        }
        if (Array.isArray(req.body.app_scenario[i])) {
            //if the scenario key has a value that is an array of items, push it into an `IN` statement
            //iter = [stage1, stage2]   -->  SQL  -->  iter IN ('stag1', stage2')
            w = w + i + " IN (";
            for (var j in req.body.app_scenario[i]) {
                if (d > 1) {
                    w = w + ",";
                }
                w = w + "'" + req.body.app_scenario[i][j] + "'";
                d = d + 1;
            }
            w = w + ")";
        } else {
            w = w + i + " = '" + req.body.app_scenario[i] + "'";
        }
        args.push(req.body.app_scenario[i]);
        c = c + 1;
    };
    return { c, w };
}

//------------route to test if the process is running-------------------------------
server.get('/', (req, res) => res.send('pivotscale api is running'))

//------------build forecast baseline that is a mirror of the target period---------
server.get('/baseline', bodyParser.json(), function(req, res) {

    var sql = "";
    var path = './routes/baseline/baseline.sql';
    var args = [];

    Postgres.query("SELECT t FROM fc.sql WHERE cmd = 'baseline'", []).then((result, error) => {

        if (error) {
            console.log("fatal error pulling sql file");
            return;
        }

        sql = result.rows[0].t

        console.log(new Date().toISOString() + "-------------------------baseline build-----------------------------")

        sql = SQLTemplate(sql, {
            ...req.body,
            app_req: JSON.stringify(req.body)
        });

        console.log(sql)

        Postgres.query(sql, []).then((result, error) => {
            res.json(result[1].rows[0]);
        });

    });

});

//------------scale a selected slice by the specified amounts-----------------------
server.get('/scale', bodyParser.json(), function(req, res) {

    var sql = "";
    var where = ""; //holds the where
    var check = 1; //flag if body is empty
    var path = './routes/scale/scale.sql';


    Postgres.query("SELECT t FROM fc.sql WHERE cmd = 'scale'", []).then((result, error) => {

        if (error) {
            console.log("fatal error pulling sql file")
            return
        }

        sql = result.rows[0].t;

        ({ c: check, w: where } = build_where(req, check, where));
        //if there was no body sent, return with nothing
        //if (c == 1) {
        //    res.send("no body was sent");
        //    return;
        //}
        console.log(new Date().toISOString() + "-------------------------scale type adjustment----------------------")

        sql = SQLTemplate(sql, {
            app_req: JSON.stringify(req.body),
            app_forecast_name: req.body.app_forecast_name,
            app_where: where
        });

        //execute the sql and send the result

        Postgres.query(sql, []).then((result, error) => {
            res.json(result.rows[0]);
        });
    });
});