server.py

from flask import Flask, request
from datetime import datetime
import time

app = Flask(__name__)
messages = []
users = {}


@app.route("/")
def hello():
    return "Hello! You are using Somi Messenger! Here is its <a href='/status'>status</a>"


@app.route("/status")
def status():
    return {
        "status": "OK",
        "name": "Somi Messenger",
        "time": datetime.now().strftime("%H:%M:%S %d/%m/%Y"),
        "users_count": len(users),
        "messages_count": len(messages)
    }


@app.route("/send_message")
def send_message():
    username = request.json["username"]
    password = request.json["password"]
    text = request.json["text"]

    if username in users:
        if users[username] != password:
            return {"OK": False}
    else:
        users[username] = password

    messages.append({"username": username, "text": text, "timestamp": time.time()})
    return {"OK": True}


@app.route("/get_messages")
def get_messages():
    after = float(request.args["after"])

    result = []

    for message in messages:
        if message["timestamp"] > after:
            result.append(message)
    return {
        "messages": result
    }


app.run()