From 1034bcb00e1efd12147bad83bd313e339aea7fc7 Mon Sep 17 00:00:00 2001
From: arbach <dev@dev.com>
Date: Sat, 5 Dec 2020 10:50:55 -0600
Subject: [PATCH] main.py

---
 main.py | 97 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 97 insertions(+)
 create mode 100644 main.py

diff --git a/main.py b/main.py
new file mode 100644
index 0000000..ee224a7
--- /dev/null
+++ b/main.py
@@ -0,0 +1,97 @@
+#!/usr/bin/env python3
+
+import socket
+import select
+import time
+import sys
+import os
+
+buffer_size = 4096
+delay = 0.0001
+SERVER = os.getenv('SERVICE_HOST').split(':')
+forward_to = (SERVER[0], int(SERVER[1]))
+
+
+class Forward:
+    def __init__(self):
+        self.forward = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+
+    def start(self, host, port):
+        try:
+            self.forward.connect((host, port))
+            return self.forward
+        except Exception as e:
+            print(e)
+            return False
+
+
+class TheServer:
+    input_list = []
+    channel = {}
+
+    def __init__(self, host, port):
+        self.server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        self.server.bind((host, port))
+        self.server.listen(200)
+
+    def main_loop(self):
+        self.input_list.append(self.server)
+        while 1:
+            time.sleep(delay)
+            ss = select.select
+            inputready, outputready, exceptready = ss(self.input_list, [], [])
+            for self.s in inputready:
+                if self.s == self.server:
+                    self.on_accept()
+                    break
+
+                self.data = self.s.recv(buffer_size)
+                if len(self.data) == 0:
+                    self.on_close()
+                    break
+                else:
+                    self.on_recv()
+
+    def on_accept(self):
+        forward = Forward().start(forward_to[0], forward_to[1])
+        clientsock, clientaddr = self.server.accept()
+        if forward:
+            print(clientaddr, "has connected")
+            self.input_list.append(clientsock)
+            self.input_list.append(forward)
+            self.channel[clientsock] = forward
+            self.channel[forward] = clientsock
+        else:
+            print("Can't establish connection with remote server.")
+            print("Closing connection with client side", clientaddr)
+            clientsock.close()
+
+    def on_close(self):
+        print(self.s.getpeername(), "has disconnected")
+        # remove objects from input_list
+        self.input_list.remove(self.s)
+        self.input_list.remove(self.channel[self.s])
+        out = self.channel[self.s]
+        # close the connection with client
+        self.channel[out].close()  # equivalent to do self.s.close()
+        # close the connection with remote server
+        self.channel[self.s].close()
+        # delete both objects from channel dict
+        del self.channel[out]
+        del self.channel[self.s]
+
+    def on_recv(self):
+        data = self.data
+        # here we can parse and/or modify the data before send forward
+        print(data)
+        self.channel[self.s].send(data)
+
+
+if __name__ == '__main__':
+    server = TheServer('0.0.0.0', 8880)
+    try:
+        server.main_loop()
+    except KeyboardInterrupt:
+        print("Ctrl C - Stopping server")
+        sys.exit(1)