HTTP Post into File Writing Service

post-request-writer.py

#!/usr/bin/env python3
from http.server import BaseHTTPRequestHandler, HTTPServer
import logging
import os
from datetime import datetime

class PostRequestWritingServer(HTTPServer):
	_counter = 0

	class FileWritingPostRequestHandler(BaseHTTPRequestHandler):
		
		def _set_response(self):
			self.send_response(200)
			self.send_header("Content-type", "text/html")
			self.end_headers()			

		def do_POST(self):
			timestamp = datetime.utcnow()
			content_length = int(self.headers['Content-Length'])
			content = self.rfile.read(content_length).decode('utf-8')
			ip = self.headers['X-Forwarded-For']
			agent=self.headers['User-Agent']
			logging.info("Received %d bytes from %s (%s) %s", content_length, ip, agent, timestamp)
			timestamp_string = timestamp.strftime('%Y-%m-%dT%H:%M:%S,%f%z')
			dump = f"Time: {timestamp_string}\nIP: {ip}\nUser-Agent: {agent}\nContent:\n{content}"
			filepath = self.server._out_dir_path
			filename_time_string = timestamp.strftime('%Y%m%d%H%M%S%f')
			filename = f"post_{filename_time_string}_{self.server._counter}.txt"
			self.server._counter += 1
			out_path = os.path.join(filepath, filename)
			with open(out_path, 'w') as file:
				file.write(dump)
			self._set_response()


	def __init__(self, server_address, out_dir_path):
		self._out_dir_path = out_dir_path
		super().__init__(server_address, self.FileWritingPostRequestHandler);


def run(port=8080, outdir='.'):
	logging.basicConfig(format='%(asctime)s %(levelname)s: %(message)s', level=logging.INFO)	
	server_address = ('', port)
	server = PostRequestWritingServer(server_address, outdir)
	logging.info("Starting server on port %d...\n", port)
	try:
		server.serve_forever()
	except KeyboardInterrupt:
		pass
	server.server_close()
	logging.info("Stopping server...\n")

if __name__ == '__main__':
	import argparse
	
	parser = argparse.ArgumentParser(description="HTTP Server that dumps POST requests")
	parser.add_argument('-p', '--port', type = int, default=8080, help = "The port to listen to (default: 8080)")
	parser.add_argument('-o', '--out', help = "The output directory to write to (default: current directory)")
	args = parser.parse_args()

	run(port=args.port, outdir=args.out)

post-request-writer.service

[Unit]
Description=Post Request Writer Service
After=network.target

[Service]
Type=simple
User=http
Group=http
ExecStart=/usr/local/bin/post-request-writer.py -p 7800 -o /srv/http/posts

[Install]
WantedBy=multi-user.target

This service writes every post request into a file. Useful for, e.g., surveys or other user data you would like to collect. You need to set X-Forwarded-For header property to get the IP address of the sender. In NGINX, you could configure it in this way:

location /my-survey/post {
    proxy_pass http://localhost:7800/;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}