(ftplib.py): Added parse150() function and FTP.ntransfercmd(). This allows

	access to the expected size of a transfer when available.

diff --git a/Lib/ftplib.py b/Lib/ftplib.py
index e24036a2019bade81761a54d24c88acc5af990e0..3ea3a25b3a60beb35073fdc5a976c01029f3667f 100644 (file)
--- a/Lib/ftplib.py
+++ b/Lib/ftplib.py
@@ -245,13 +245,16 @@ class FTP:
                resp = self.sendport(host, port)
                return sock
 
-       def transfercmd(self, cmd):
+       def ntransfercmd(self, cmd):
                '''Initiate a transfer over the data connection.
                If the transfer is active, send a port command and
                the transfer command, and accept the connection.
                If the server is passive, send a pasv command, connect
                to it, and start the transfer command.
-               Either way, return the socket for the connection'''
+               Either way, return the socket for the connection and
+               the expected size of the transfer.  The expected size
+               may be None if it could not be determined.'''
+               size = None
                if self.passiveserver:
                        host, port = parse227(self.sendcmd('PASV'))
                        conn = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
@@ -265,7 +268,15 @@ class FTP:
                        if resp[0] <> '1':
                                raise error_reply, resp
                        conn, sockaddr = sock.accept()
-               return conn
+               if resp[:3] == '150':
+                       # this is conditional in case we received a 125
+                       size = parse150(resp)
+               return conn, size
+
+       def transfercmd(self, cmd):
+               '''Initiate a transfer over the data connection.  Returns
+               the socket for the connection.  See also ntransfercmd().'''
+               return self.ntransfercmd(cmd)[0]
 
        def login(self, user = '', passwd = '', acct = ''):
                '''Login, default anonymous.'''
@@ -450,6 +461,22 @@ class FTP:
                del self.file, self.sock
 
 
+import regex
+_150_re = regex.compile("150 .* (\([0-9][0-9]*\) bytes)", regex.casefold)
+
+def parse150(resp):
+    '''Parse the '150' response for a RETR request.
+    Returns the expected transfer size or None; size is not guaranteed to
+    be present in the 150 message.
+    '''
+    if resp[:3] != '150':
+       raise error_reply, resp
+    length = _150_re.match(resp)
+    if length >= 0:
+       return string.atoi(_150_re.group(1))
+    return None
+
+
 def parse227(resp):
        '''Parse the '227' response for a PASV request.
        Raises error_proto if it does not contain '(h1,h2,h3,h4,p1,p2)'