Instructions for Creating an HTTP Server in Python

Introduce

What is a web server?

overview

A web server is a computer that stores web content.
A web server used to serve websites on the internet or intranet.
It stores pages, scripts, progarmsor files multimediaand use the protocol HTTPto send the file to the web browser.
Some famous web servers such as Nginx web server , Apache web server , IIS web server , Light Speed web server .

Method of web server or dynamic.

For example, the user wants to see a website such as www.google.com, the user enters the url into the web browser provided the user needs an Internet connection. The protocol set TCP/IPis then used to establish the connection.
When the connection is established, the client sends a request through HTTPand waits for a response from the server. On the other side, the server receives the request, processes the request, and sends the response back to the client.

HTTP protocol

The protocol HTTPstands for Hyper Text Transfer Protocol.
It is an application-layer protocol that allows web applications to communicate and exchange data.
It is a protocol based TCP/IP.
It is used to provide content: hình ảnh, âm thanh, video, tài liệu…
Using HTTPis the most convenient way to move data quickly and reliably on the web.

Example of HTTP message

How to create HTTP Server in python

Python has a number of built-in libraries to make web serverit easier. For example, you can create one SimpleHTTPServerwith a simple command:

With python2

python -m SimpleHTTPServer + port (if not write anything default is 8000)

With python3

python3 -m http.server + port (if not write anything default is 8000)

But you cannot customize your server.

Create an HTTPServer Project

Create HTML and CSS files

index.html

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <title>Page Title</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="/main.css">
</head>
<body>
    <h1>Sun* Cyber Security Research</h1>
</body>
</html>

main.css

@import url('https://fonts.googleapis.com/css?family=IBM+Plex+Sans+Condensed:100,200,300,400');

body{
    background-color: #222;
}

h1{
    color: white;
    padding: 20px 40px;
    margin: 0 auto;
    background-color: rgba(255, 255, 255, .7);
    display: inline-block;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translateY(-50%) translateX(-50%);
    border-radius: 4px;
    border-bottom: 5px solid rgba(150, 150, 150, 1);
    font-weight: 200;
    font-family: 'IBM Plex Sans Condensed', sans-serif;
}

Project setup

server.py

from http.server import BaseHTTPRequestHandler
import os
class Server(BaseHTTPRequestHandler):
    def do_GET(self):
        if self.path == '/':
            self.path = '/index.html'
        try:
            split_path = os.path.splitext(self.path)
            request_extension = split_path[1]
            if request_extension != ".py":
                f = open(self.path[1:]).read()
                self.send_response(200)
                self.end_headers()
                self.wfile.write(bytes(f, 'utf-8'))
            else:
                f = "File not found"
                self.send_error(404,f)
        except:
            f = "File not found"
            self.send_error(404,f)

from http.server import BaseHTTPRequestHandler
import os

BaseHTTPRequestHandler is used to handle HTTP requests to the server.
Also BaseHTTPRequestHandlersupports some of the following properties and methods:
do_GET(): This method deals with GET requests.
do_POST(): This method deals with POST requests.
path: This property returns the path of the request.
send_error(): This method returns an HTTP error to the client.

First define a means do_GET(). This method runs when there is a GET request sent.

self.path == ‘/’ check if the post request is an index page and if it’s a page indexthen assign the path to the index self.path == '/ index.html` .
Next try to read the files that the user is trying to access except to file pythonavoid leaks source code.
If the requested file is found, the server sends a response 200. 200is the response that whenever you visit a website successfully.
If the requested file cannot be found, serveran invalid request file error code is sent.
Use the bytes()encode method utf-8to convert text to bytes.

main.py

import time
from http.server import HTTPServer
from server import Server

HOST_NAME = 'localhost'
PORT = 8000

if __name__ == "__main__":
    httpd = HTTPServer((HOST_NAME,PORT),Server)
    print(time.asctime(), "Start Server - %s:%s"%(HOST_NAME,PORT))
    try:
        httpd.serve_forever()
    except KeyboardInterrupt:
        pass
    httpd.server_close()
    print(time.asctime(),'Stop Server - %s:%s' %(HOST_NAME,PORT))

import time
from http.server import HTTPServer
from server import Server

Time used to control time startand stopserver.
HTTPServer is a subclass of socketserver.TCPServer that creates and listens for HTTP sockets, sends requests to the processor.

Configure the server with two constants HOST_NAME = 'localhost',PORT = 8000with which HOST_NAME = 'localhost'to run the server on localhost and which PORT = 8000is the port where the application will be run.

httpd = HTTPServer((HOST_NAME,PORT),Server)

Call the HTTPServer that python provides with the first argument as a pair (HOST_NAME,PORT)and the second argument as a class Serverto handle that was set earlier.

try:
    httpd.serve_forever()
except KeyboardInterrupt:
    pass
httpd.server_close()
print(time.asctime(),'Stop Server - %s:%s' %(HOST_NAME,PORT))

The next block to startand the stopserver, when receiving an interrupt signal from the server keyboard will close the connection httpd.server_close().

Now we start the server by running the command:

python3 main.py

Open a browser and enter the url http: // localhost: 8000
And here is the response from the server:

So we have successfully created a simple HTTP Server with python, in addition we can write more methods such as the HEAD, POST ...Server can handle more methods.

#python #programming