# Code attribution: Yiyin Shen, Tyler Caraza-Harter
# Imports
from flask import Flask, request, redirect, Response
import matplotlib.pyplot as plt
import time
import pandas

# Build a webpage that keeps track of visitors
app = Flask("app")

visitors = []
times = {}

@app.route("/")
def home():
    global visitors, times
    rate = 3
    ip = request.remote_addr
    ua = request.user_agent.string
    visitors.append([ip, ua])
    now = time.time()
    if ip in times:
        td = now - times[ip]
        if td < rate:
            return Response("Please come back in " + str(rate - td) + " seconds.", status = 429, headers = {"Retry-After": str(rate)})
        else:
            times[ip] = now
            return "Welcome back, [" + ip + "] " + ua
    else:
        times[ip] = now
        return "Hello, [" + ip + "] " + ua

@app.route("/visitors")
def display():
    df = pandas.DataFrame(visitors, columns = ["IP", "User Agent"])
    return df.to_html()

app.run(host = "0.0.0.0", debug = False, threaded = False)

 * Serving Flask app 'app'
 * Debug mode: off

WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead.
 * Running on all addresses (0.0.0.0)
 * Running on http://127.0.0.1:5000
 * Running on http://192.168.1.87:5000
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