Why is website responding with 404 when sending raw HTTP request?

August 28, 2022

I try to figure out why webhook.site is responding with the error 404 when I´m sending an HTTP POST request with a TCP client into the endpoint:

import socket

HOST = "46.4.105.116"
PORT = 80

Payload = "POST /62b69843-f5b2-4d49-81b7-c3a61f6bdeda HTTP/1.1\r\n"
Payload += "Host: Python test\r\n"
Payload += "Content-Length: {}\r\n".format(0)
Payload += "\r\n"
print(Payload)

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
    s.connect((HOST, PORT))
    s.sendall(str.encode(Payload))
    data = s.recv(1024)

print(f"Received {data!r}")

Response:

Received b'HTTP/1.1 404 Not Found\r\nServer: nginx\r\nContent-Type: text/html; charset=UTF-8\r\nTransfer-Encoding: chunked\r\nVary: Accept-Encoding\r\nCache-Control: no-cache, private\r\ndate: Sun, 28 Aug 2022 17:32:45 GMT\r\n\r\n610\r\n<!DOCTYPE html>\n<html lang="en">\n    <head>\n        <meta charset="utf-8">\n        <meta name="viewport" content="width=device-width, initial-scale=1">\n\n        <title>Not Found</title>\n\n        <!-- Fonts -->\n        <link rel="dns-prefetch" href="//fonts.gstatic.com">\n        <link href="https://fonts.googleapis.com/css?family=Nunito" rel="stylesheet">\n\n        <!-- Styles -->\n        <style>\n            html, body {\n                background-color: #fff;\n                color: #636b6f;\n                font-family: \'Nunito\', sans-serif;\n                font-weight: 100;\n                height: 100vh;\n                margin: 0;\n            }\n\n            .full-height {\n                height: 100vh;\n            }\n\n            .flex-center {\n                align-items: center;\n                display: f'

What is the issue here?