Implement multithreaded server

lib/nntp/tiny/server.py

@@ -1,8 +1,11 @@
 import enum
+import socket
+import threading
 
 from typing import Callable
 
 from nntp.tiny.newsgroup import Newsgroup
+from nntp.tiny.session   import Session
 
 class ServerCapability(enum.Flag):
     NONE = 0
@@ -22,3 +25,17 @@ class Server():
 
         for newsgroup in db.query(Newsgroup).each():
             self.newsgroups[newsgroup.name.casefold()] = newsgroup
+
+    def run(self):
+        listener = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        listener.bind(('localhost', 1190))
+        listener.listen()
+
+        while True:
+            sock, addr = listener.accept()
+
+            session = Session(self, sock)
+            thread  = threading.Thread(target=session.handle)
+            thread.start()
+
+        listener.close()

lib/nntp/tiny/session.py

@@ -9,7 +9,6 @@ from typing import Optional
 
 from nntp.tiny.buffer    import LineBuffer, BufferOverflow
 from nntp.tiny.db        import Database
-from nntp.tiny.server    import Server, ServerCapability
 from nntp.tiny.response  import Response, ResponseCode
 from nntp.tiny.newsgroup import Newsgroup
 from nntp.tiny.message   import Message
@@ -104,8 +103,8 @@ class Session():
 
     RE_SPLIT = re.compile(r'\s+')
 
-    def __init__(self, server: Server, sock: socket.socket):
+    def __init__(self, server, sock: socket.socket):
-        self.server: Server      = server
+        self.server              = server
         self.db: Database        = server.connect_to_db()
         self.sock: socket.socket = sock
         self.buf: LineBuffer     = LineBuffer()
@@ -739,7 +738,7 @@ class Session():
     def greet(self):
         return self.respond(ResponseCode.NNTP_SERVICE_READY_POST_PROHIBITED)
 
-    def handle(self):
+    def handle_command(self):
         line = self.readline()
 
         if line == '':
@@ -761,3 +760,11 @@ class Session():
         except Exception as e:
             traceback.print_exception(e)
             return self.respond(ResponseCode.NNTP_COMMAND_UNAVAILABLE)
+
+    def handle(self):
+        self.greet()
+
+        while self.state & SessionState.ACTIVE:
+            self.handle_command()
+
+        self.sock.close()