add recipes of 'Create TCP Server'.

README.md

@@ -60,6 +60,8 @@
   - [Synchronization Primitives - `Event` (For Processes)](recipes/core/synchronization_event_processes)
   - [Synchronization Primitives - Mutex Lock `Lock` (For Threads)](recipes/core/synchronization_lock_threads)
   - [Synchronization Primitives - Mutex Lock `Lock` (For Processes)](recipes/core/synchronization_lock_processes)
+- Networks
+  - [Create TCP Server](recipes/core/tcp_server)
 
 ## License
 

recipes/core/tcp_server.md

@@ -0,0 +1,45 @@
+# Create TCP Server
+
+```python
+import socketserver
+
+class MyTCPHandler(socketserver.BaseRequestHandler):
+    """
+    The request handler class for our server.
+
+    It is instantiated once per connection to the server, and must
+    override the handle() method to implement communication to the
+    client.
+    """
+
+    def handle(self):
+        # self.request is the TCP socket connected to the client
+        self.data = self.request.recv(1024).strip()
+        print(f'{self.client_address[0]} wrote: {self.data}')
+        # just send back the same data, but upper-cased
+        self.request.sendall(self.data.upper())
+
+
+class MyTCPHandler(socketserver.StreamRequestHandler):
+
+    def handle(self):
+        # self.rfile is a file-like object created by the handler;
+        # we can now use e.g. readline() instead of raw recv() calls
+        self.data = self.rfile.readline().strip()
+        print(f'{self.client_address[0]} wrote: {self.data}')
+        # Likewise, self.wfile is a file-like object used to write back
+        # to the client
+        self.wfile.write(self.data.upper())
+
+
+if __name__ == '__main__':
+    # Create the server, binding to localhost on port 9999
+    with socketserver.TCPServer(('localhost', 9999), MyTCPHandler) as server:
+        # Activate the server; this will keep running until you
+        # interrupt the program with Ctrl-C
+        server.serve_forever()
+```
+
+## References
+
+More details to see [`socketserver`- Standard Networks Server Framework on Python Handbook](https://leven-cn.github.io/python-handbook/recipes/core/socketserver).