Update servefiles.py

making parameter count verification strict
adding file extension verification when a file is given as parameter
adding output error to stderr
adding hostPort choice (for the HTTP server)
rename 'directory' into 'target_path'
rename 'payload' into 'file_list_payload'
adding comments
some small cleanups (indent, print(), ...)

servefiles/servefiles.py

@@ -1,4 +1,6 @@
 #!/usr/bin/env python
+# coding: utf-8 -*-
+
 import os
 import socket
 import struct
@@ -8,79 +10,78 @@ import time
 import urllib
 
 try:
-	from SimpleHTTPServer import SimpleHTTPRequestHandler
-	from SocketServer import TCPServer
-	from urlparse import urljoin
-	from urllib import pathname2url, quote
+    from SimpleHTTPServer import SimpleHTTPRequestHandler
+    from SocketServer import TCPServer
+    from urlparse import urljoin
+    from urllib import pathname2url, quote
 except ImportError:
-	from http.server import SimpleHTTPRequestHandler
-	from socketserver import TCPServer
-	from urllib.parse import urljoin, quote
-	from urllib.request import pathname2url
+    from http.server import SimpleHTTPRequestHandler
+    from socketserver import TCPServer
+    from urllib.parse import urljoin, quote
+    from urllib.request import pathname2url
 
-if len(sys.argv) < 3:
-	print("Usage: " + sys.argv[0] + " <ip> <file/directory> [host ip]")
-	sys.exit(1)
+if len(sys.argv) < 3 or len(sys.argv) > 5:
+    print('Usage:', sys.argv[0], '<target ip> <file / directory> [host ip] [host port]')
+    sys.exit(1)
 
-ip = sys.argv[1]
-directory = sys.argv[2]
+accepted_extension = ('.cia', '.tik')
+target_ip = sys.argv[1]
+target_path = sys.argv[2]
+hostPort = 8080  # default value
 
-if not os.path.exists(directory):
-	print(directory + ": No such file or directory.")
-	sys.exit(1)
+if not os.path.exists(target_path):
+    print(target_path, ': No such file or directory.', file=sys.stderr)
+    sys.exit(1)
 
 if len(sys.argv) >= 4:
-	hostIp = sys.argv[3]
+    hostIp = sys.argv[3]
+    if len(sys.argv) == 5:
+        hostPort = int(sys.argv[4])
 else:
-	hostIp = [(s.connect(('8.8.8.8', 53)), s.getsockname()[0], s.close()) for s in [socket.socket(socket.AF_INET, socket.SOCK_DGRAM)]][0][1]
+    print('Finding host ip ...')  # loop over network address to find one
+    hostIp = [(s.connect(('8.8.8.8', 53)), s.getsockname()[0], s.close()) for s in [socket.socket(socket.AF_INET, socket.SOCK_DGRAM)]][0][1]
 
-print("Preparing data...")
+print('Preparing data ...')
+baseUrl = hostIp + ':' + str(hostPort) + '/'
 
-baseUrl = hostIp + ":8080/"
-payload = ""
-
-if os.path.isfile(directory):
-	payload += baseUrl + quote(os.path.basename(directory))
-	directory = os.path.dirname(directory)
+if os.path.isfile(target_path) and target_path.endswith(accepted_extension):
+    file_list_payload = baseUrl + quote(os.path.basename(target_path))
+    directory = os.path.dirname(target_path)  # get file directory
 else:
-	for file in [ file for file in next(os.walk(directory))[2] if file.endswith(('.cia', '.tik')) ]:
-		payload += baseUrl + quote(file) + "\n"
+    directory = target_path  # it's a directory
+    file_list_payload = ''  # init the payload before adding lines
+    for file in [file for file in next(os.walk(target_path))[2] if file.endswith(accepted_extension)]:
+        file_list_payload += baseUrl + quote(file) + '\n'
 
-if len(payload) == 0:
-	print("No files to serve.")
-	sys.exit(1)
+if len(file_list_payload) == 0:
+    print('No files to serve.', file=sys.stderr)
+    sys.exit(1)
 
-payloadBytes = payload.encode("ascii")
+file_list_payloadBytes = file_list_payload.encode('ascii')
 
-if not directory == "":
-	os.chdir(directory)
+if directory and directory != '.':  # doesn't need to move if it's already the current working directory
+    os.chdir(directory)  # set working directory to the right folder to be able to serve files
 
-print("")
-print("URLS:")
-print(payload)
-print("")
+print('\nURLS (payload send) :')
+print(file_list_payload, '\n')
 
-print("Opening HTTP server on port 8080...")
-
-server = TCPServer(("", 8080), SimpleHTTPRequestHandler)
+print('Opening HTTP server on port :', hostPort)
+server = TCPServer(('', hostPort), SimpleHTTPRequestHandler)
 thread = threading.Thread(target=server.serve_forever)
 thread.start()
 
 try:
-	print("Sending URL(s) to " + ip + ":5000...")
-
-	sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-	sock.connect((ip, 5000))
-	sock.sendall(struct.pack('!L', len(payloadBytes)) + payloadBytes)
-	while len(sock.recv(1)) < 1:
-		time.sleep(0.05)
-
-	sock.close()
+    print('Sending URL(s) to', target_ip, 'on port 5000 ...')
+    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    sock.connect((target_ip, 5000))
+    sock.sendall(struct.pack('!L', len(file_list_payloadBytes)) + file_list_payloadBytes)
+    while len(sock.recv(1)) < 1:
+        time.sleep(0.05)
+    sock.close()
 except Exception as e:
-	print("Error: " + str(e))
-	server.shutdown()
-	sys.exit(1)
-
-print("Shutting down HTTP server...")
+    print('An Error occurred :', str(e), file=sys.stderr)
+    server.shutdown()
+    sys.exit(1)
 
+print('Shutting down HTTP server ...')
 server.shutdown()