examples/flask/22/app.py
from flask import Flask, jsonify, render_template, request
import time
app = Flask(__name__)

@app.route("/")
def main():
    return render_template('main.html', reload = time.time())

@app.route("/api/info")
def api_info():
    info = {
       "ip" : "127.0.0.1",
       "hostname" : "everest",
       "description" : "Main server",
       "load" : [ 3.21, 7, 14 ]
    }
    return jsonify(info)

@app.route("/api/calc")
def add():
    a = int(request.args.get('a', 0))
    b = int(request.args.get('b', 0))
    div = 'na'
    if b != 0:
        div = a/b
    return jsonify({
        "a"        :  a,
        "b"        :  b,
        "add"      :  a+b,
        "multiply" :  a*b,
        "subtract" :  a-b,
        "divide"   :  div,
    })

examples/flask/22/static/math.js
$(function() {
    $.ajax({
        url: '/api/info',
        success: function(data) {
            console.log('get info');
            $('#info').html(JSON.stringify(data, null, '   '));
            $('#description').html(data['description']);
        }
    });
 
    $('#calc').click(function() {
        $('#info').css('display', "none");
        $('#description').css('display', "none");
        //console.log(url);
        $.ajax({
            url : '/api/calc?a=' + document.getElementById('a').value + '&b=' + document.getElementById('b').value,
            success: function(data) {
                $('#add').html(data['a'] + ' + ' + data['b'] + ' = ' + data['add']);
                $('#subtract').html(data['a'] + ' - ' + data['b'] + ' = ' + data['subtract']);
                $('#multiply').html(data['a'] + ' * ' + data['b'] + ' = ' + data['multiply']);
                $('#divide').html(data['a'] + ' / ' + data['b'] + ' = ' + data['divide']);
            }
        });
    });
})
examples/flask/22/templates/main.html
<html>
<head>
</head>
<body>
<input type="number" id="a">
<input type="number" id="b">
<button id="calc">Calc</button>
<div id="results">
   <div id="add"></div>
   <div id="subtract"></div>
   <div id="multiply"></div>
   <div id="divide"></div>
</div>

<pre id="info"></pre>
<div id="description"></div>

<script src="/static/jquery-3.1.1.min.js"></script>
<script src="/static/math.js?r={{reload}}"></script>
</body>
</html>