From 1eb4e072caa7df1d2986dc6ad56a063fd7a5f1ad Mon Sep 17 00:00:00 2001
From: minhtrannhat <minh@minhtrannhat.com>
Date: Wed, 29 Nov 2023 00:00:51 -0500
Subject: [PATCH] feat(UDP): commands pattern matching

- Added comments
---
 README.md           |  2 +-
 src/myftp/client.py | 62 +++++++++++++++++++++++++++++++++++----------
 src/myftp/server.py |  4 ++-
 3 files changed, 53 insertions(+), 15 deletions(-)

diff --git a/README.md b/README.md
index ddc3bc7..49f1f74 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 ## Dependencies
 
-Zero. Only python standard libs were used.
+Zero. Only python standard libs were used. Tested on Python 3.11
 
 ## Running
 
diff --git a/src/myftp/client.py b/src/myftp/client.py
index b6799c7..933f45c 100644
--- a/src/myftp/client.py
+++ b/src/myftp/client.py
@@ -1,8 +1,16 @@
 from socket import socket, AF_INET, SOCK_DGRAM
-from typing import Tuple
+from typing import Pattern, Tuple
 from argparse import ArgumentParser
 import os
 import pickle
+import re
+
+# patterns for command matchings
+# compiled for extra performance
+get_command_pattern: Pattern = re.compile(r"^get\s+[^\s]+$")
+put_command_pattern: Pattern = re.compile(r"^put\s+[^\s]+$")
+summary_command_pattern: Pattern = re.compile(r"^summary\s+[^\s]+$")
+change_command_pattern: Pattern = re.compile(r"^change\s+[^\s]+\s+[^\s]+$")
 
 # custome type to represent the hostname(server name) and the server port
 Address = Tuple[str, int]
@@ -29,18 +37,7 @@ class UDPClient:
                 client_socket.connect((self.server_name, self.server_port))
 
                 # get command from user
-                while (command := input(f"myftp> - {self.mode} - : ")) not in [
-                    "put",
-                    "get",
-                    "summary",
-                    "change",
-                    "help",
-                    "list",
-                    "bye",
-                ]:
-                    print(
-                        f"myftp> - {self.mode} - : Invalid command. Supported commands are put, get, summary, change, list and help"
-                    )
+                command = input(f"myftp> - {self.mode} - : ").strip().lower()
 
                 # handling the "bye" command
                 if command == "bye":
@@ -48,6 +45,7 @@ class UDPClient:
                     print(f"myftp> - {self.mode} - Session is terminated")
                     break
 
+                # list files available on the server
                 elif command == "list":
                     client_socket.send(command.encode())
                     encoded_message, server_address = client_socket.recvfrom(4096)
@@ -56,6 +54,44 @@ class UDPClient:
                     client_socket.close()
                     continue
 
+                # help
+                elif command == "help":
+                    continue
+
+                # get command handling
+                elif get_command_pattern.match(command):
+                    _, filename = command.split(" ", 1)
+                    print(
+                        f"myftp> - {self.mode} - : getting file {filename} from the server"
+                    ) if self.debug else None
+
+                # put command handling
+                elif put_command_pattern.match(command):
+                    _, filename = command.split(" ", 1)
+                    print(
+                        f"myftp> - {self.mode} - : putting file {filename} into the server"
+                    ) if self.debug else None
+
+                # summary command handling
+                elif summary_command_pattern.match(command):
+                    _, filename = command.split(" ", 1)
+                    print(
+                        f"myftp> - {self.mode} - : summary file {filename} from the server"
+                    ) if self.debug else None
+
+                # summary command handling
+                elif change_command_pattern.match(command):
+                    _, old_filename, new_filename = command.split()
+                    print(
+                        f"myftp> - {self.mode} - : changing file named {old_filename} into {new_filename} on the server"
+                    ) if self.debug else None
+
+                else:
+                    print(
+                        f"myftp> - {self.mode} - : Invalid command. Supported commands are put, get, summary, change, list and help. Type help for detailed usage."
+                    )
+                    continue
+
                 client_socket.send(command.encode())
                 modified_message = client_socket.recv(2048)
                 print(modified_message.decode())
diff --git a/src/myftp/server.py b/src/myftp/server.py
index 37b583d..0692db6 100644
--- a/src/myftp/server.py
+++ b/src/myftp/server.py
@@ -33,9 +33,11 @@ class UDPServer:
                     f"myftp> - {self.mode} - received message from client at {clientAddress}: {message_in_utf8}"
                 ) if self.debug else None
 
+                # check for connectivity
                 if message_in_utf8 == "ping":
                     response_message = "pong"
 
+                # list files available on server
                 elif message_in_utf8 == "list":
                     encoded_message = pickle.dumps(
                         get_files_in_directory(self.directory_path)
@@ -63,7 +65,7 @@ class UDPServer:
 
 def get_files_in_directory(directory_path: str) -> list[str]:
     file_list = []
-    for root, _, files in os.walk(directory_path):
+    for _, _, files in os.walk(directory_path):
         for file in files:
             file_list.append(file)
     return file_list