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Send body JSON with Postman in a POST method to execute procedure in ms sql server

I want to send a JSON (body) on Postman with POST method and receive a result.
Im a trainee and my boss asked me this. I've been looking in web for a week and didn't find. I said to him that method to receive a data is GET, but he said that GET has a limit on URL. If the stored procedure have a lot of parameters we will not receive the expected result, so a I have to use Post method.
This is my code to connect to ms sql server:
var express = require('express');
var app = express();
var sql = require('mssql');
var config = {
user: 'MY_USER',
password: 'MY_PASS',
server: 'MY_SERVER',
database: 'MY_DB'
};
Searching in google I found a way to execute a procedure with GET method. In the browser I put the value I want and I receive the result, but is not still what he wants. The code is:
app.get('/get/:pNU_EST001', function (req, res) {
//conexão com o DB
sql.connect(config, function(){
var request = new sql.Request();
request.input('pNU_EST001', req.params.pNU_EST001);
request.execute('dbo.ESTSP004_ConsultaLivrosEmprestadosAluno_XX', function(err, recordsets, returnValue, affected) {
if(err) console.log(err);
res.send(recordsets);
//res.end(JSON.stringify(recordsets)); /*--- result in JSON format ---*/
});
});
});
On Postman he showed me a example with DB2, but I couldn't see the code. On Post Method, on HEADERS it has two key:
KEY => Content-Type (value: application/json) // KEY => Accept (value: application/json)
And in his example, on BODY, he wrote a JSON like: { "pNU_EST001" : "3"} and received the related result below. That's what I need.

Express has a few other verbs to use you are using
app.get but there is also app.post if you change your code to use the latter instead it will handle a post request
app.post('/path', function (req, res) {
Then in express to get values from the POST body you get that from
req.body property
So in your case you would want to use req.body.pNU_EST001 instead of req.params.pNU_EST001

How do I use client side JavaScript to find and return data from MongoDB and a Node.js server with no framework?

I have read all the questions on SO that I could find. They all use Express, Mongoose or they leave something out. I understand that Node.js is the server. I understand the MongoDB require is the driver the Node.js server uses to open a connection to the MongoDB. Then, on the server, I can do (from the documentation):
var MongoClient = require('mongodb').MongoClient;
var assert = require('assert');
var ObjectId = require('mongodb').ObjectID;
var url = 'mongodb://localhost:27017/test';
var findRestaurants = function(db, callback) {
var cursor =db.collection('restaurants').find( );
cursor.each(function(err, doc) {
assert.equal(err, null);
if (doc != null) {
console.dir(doc);
} else {
callback();
}
});
};
// Connect to the db
MongoClient.connect(url, function(err, db) {
assert.equal(null, err);
findRestaurants(db, function() { //I don't want to do this as soon as the server starts
db.close();
});
});
//if I put findRestaurant here,
function findRestaurant(data){
}
How do I call it from the client?
I do not want to find data as soon as I start the server. I realize those are examples, but what I cannot find is a way where the client requests some data and where the Node.js server returns it.
I have seen close examples using jQuery, Angular on the client, and then Express, Mongoose, Meteor, , etc.
All I want to understand is how I make this request from the client's browser. I can do that with XMLhttpRequest(), so I can put that part together, I believe. But, any example is appreciated.
But what is waiting on the Node.js side of things (how do I set up my function to be called once the server is listening)?
How do I create a function on the server side, maybe "GetRestaurants" and have that return the data it gets using find()?
I cannot find this information, this simple, anywhere. Is it too complicated to do the example without a framework?
I do not wish to copy and paste from something using Express, etc. without understanding what's going on. Most explanations never say, this goes on the Node.js side. This is client. I know I am expected to do my own research, but I am not putting it together, too used to RDBMSes, IIS, Apache, PHP, and so on.
I believe I have a fundamental misunderstanding of what's going on in the paradigm.
Please. No REST API creation, no frameworks of any kind on Node.js other than using the MongoDB library (unless there is an absolute requirement), not even jQuery, Angular, Jade, or anything else for the client side, straight up JavaScript on all sides.
I have seen questions like this,
How to display data from MongoDB to the frontend via Node.js without using a framework
But they do not show what I am asking. They do it all at once, as soon as the database connects. What if I want to do a delete or insert or find? There are many SO questions like this, but I have not hit the one that shows what I am looking for.

This should give the guidance. Once you go to a browser and type http://localhost:5155 the callback function (request, response) { will be called and the request to db will be made. Make sure you get response and then start working on the client side code:
const http = require('http');
const MongoClient = require('mongodb').MongoClient;
const assert = require('assert');
const url = 'mongodb://localhost:27017/test';
const server = http.createServer(function (request, response) {
getData(function (data) {
response.end(data);
});
});
function getData(callback) {
// Connect to the db
MongoClient.connect(url, function (err, db) {
assert.equal(null, err);
findRestaurants(db, function (data) {
db.close();
callback(data);
});
});
const findRestaurants = function (db, callback) {
const cursor = db.collection('restaurants').find();
const data = [];
cursor.each(function (err, doc) {
assert.equal(err, null);
data.push(doc);
if (doc === null) {
callback(data);
}
});
};
}
server.listen(5155);

any way to send a function with socket.io?

guys.
I want to send a function to browser with socket.io, but failed to do it.
On server side, I response a function with emit, but I get a undefined on browser.
Is there any way to get a function from server with socketio?
there is my code.
// server.js
var static = require('node-static');
var http = require('http');
var file = new(static.Server)();
var app = http.createServer(function(req, res) {
file.serve(req, res);
}).listen(8000);
io = require('socket.io').listen(app);
io.sockets.on('connection', function(socket) {
socket.on('schedule', function() {
console.log('SCHEDULE TASK');
socket.emit('schedule', function() { console.log('hello world'); });
});
});
// client.js
var socket = io.connect('http://localhost:8000');
socket.on('schedule', function(fn) {
fn();
});
socket.emit('schedule');

You cannot send an actual function. You could send a string of Javascript and then you could turn that into a function in the client.
But, I'd suggest you really ought to rethink what you're trying to do here. Generally, the client already has the code it needs (from the script tags that it downloaded) and you send the client data which it then passes to the code it already has or data that it uses to make decisions about which code that it already has to call.
If you show us the real world problem you're trying to solve, we can likely suggest a much better solution than sending a string of Javascript code to the client.
If you really wanted to send a function, you would have to turn it into a string first, send the string, then use the string to turn it back into a function in the client by using a Function object or eval() or creating your own dynamic script tag with inline source.

You can only send strings via socket.io, not functions. That being said, I suggest you to send function names instead.
//server.js
socket.emit('schedule', 'helloworld');
//client.js
function helloworld(){
console.log('hello world');
}
socket.on('schedule',function(name){
window[name](); //hello world
});

Socket IO 1.2 Query Parameters

I can't figure out how to retrieve query parameters on the server side for socket.io
1.2.1
Here's my client side code
var socket = io('http://localhost:3000/',{_query:"sid=" + $('#sid').attr('data-sid') + "&serial=" + $('#serial_tracker').text()});
and the server side:
io.use(function(socket,next){ //find out if user is logged in
var handshake = socket.request;
console.log(socket.request._query);
handshake.sid = handshake.query.sid;
}
socket.request._query is:
{ EIO: '3', transport: 'polling', t: '1419909065555-0' }
Does anyone know how query parameters work in socket io 1.2.1?
Thanks for any help and if you need any more information, just ask me.

When sending handshake query data to socket.io, use the following property name in the object:
{
query: 'token=12345'
}
I see above you used _query for a property name instead.
You should be able to access the query information at socket.request._query at that point. I'm not sure if there is a better way to get a hold of that data? I'm guessing yes, since they put an underscore in front of it, but I haven't found a better way yet.
Here's the full example of a connect query that is working for me (forgive the formatting, I'm copy/pasting this out of different node modules into an inline solution).
Server (using socket 1.2.1 nodejs):
var restify = require('restify');
var api = restify.createServer();
var socketio = require('socket.io');
var io = socketio.listen(api.server); // api is an instance of restify, listening on localhost:3000
io.use(function(socket, next) {
// socket.request._query.token is accessible here, for me, and will be '12345'
next();
});
api.listen(3000, function() {
console.log('%s listening at %s', api.name, api.url);
});
Client (chrome browser using the client library located at https://cdn.socket.io/socket.io-1.2.1.js):
var socket = io.connect('http://localhost:3000/', { query: 'token=12345' });

Sending client side form input to server side database query via Node.js and return results to client

I am developing a web application where the user can type in a "device id" on the web page (we have 100's of devices out on the field in production use each with a unique ID), that result entered by the user will be sent to the Node.js server that in return will store it into a variable and use it in a SQL Query to retrieve results about that particular device from the database server and then display the results back to the client web page.
Currently the form input feature has not been implemented yet even though I've already coded the form code in html.
The program works fine as it is if I were to manually change the DEVICE_ID to the device I wish to retrieve data from in the code but of course I want to be able to enter this on the client page instead of me having to change it in the server-side source code manually.
"use strict";
var pg = require('pg').native;
var http = require('http');
var $ = require('cheerio');
var fs = require('fs');
var url = require('url');
var htmlString = fs.readFileSync('index.html').toString();
var parsedHTML = $.load(htmlString);
var dbUrl = "tcp://URL HERE/";
// The Sign-ID
var DEVICE_ID = '2001202';
// Create the http server
http.createServer(function (request, response) {
var request = url.parse(request.url, true);
var action = request.pathname;
// Connect and query the database
pg.connect(dbUrl, function(err, client) {
// The complete sql query for everything that's needed for the app!
client.query("SQL QUERY IS HERE" + DEVICE_ID + "etc..",
function (err, result) {
// Remaining program code is here that performs DOM based
// manipulation to display results returned from the server
// to the client side page.
// Time to Render the document and output to the console
console.log(parsedHTML.html());
// Render the document and project onto browser
response.end(parsedHTML.html());
}
); // End client.query
}); // End pg.connect
}).listen(8080); // End http.CreateServer
pg.end();
I've considered the following:
1) Use An OnClick() function from within the HTML code, like this:
onclick="lookupSignID()
Then include an external JS file from within the HTML that includes the lookupSignID() function however I soon found out this is only performing client-side function and is not what I want.
2) AJAX is only good for if the server is generating new information by itself, therefore I can't use AJAX since the user is entering the device ID to get information from it.
3) Possibly using POST/ GET
Can anyone please advise on what course of action I should take? If solution (3) is the best way how would I go about doing this? Can it be integrated into my existed code (shown above) without many changes?
Thanks!

If you used jQuery on the client side with an AJAX POST function, and then on the server side, you have express.js, you could do this:
app.post('/deviceid', function(req, res) {
var deviceid = req.param('deviceid')
console.log(deviceid)
...
})