Solve two annoying problems with ftp URLs for Jack: when repeated
retrieving files from the same host and directory, you had to close
the previous instance before opening a new one; and retrieving a
non-existent file would return an empty file. (The latter fix relies
on maybe an undocumented property of NLST -- NLST of a file returns
just that file, while NLST of a non-existent file returns nothing. A
side effect, unfortunately, seems to be that now ftp-retrieving an
*empty* directory may fail. Ah well.)
diff --git a/Lib/urllib.py b/Lib/urllib.py
index a16529a..b9a82d1 100644
--- a/Lib/urllib.py
+++ b/Lib/urllib.py
@@ -497,6 +497,7 @@
self.init()
def init(self):
import ftplib
+ self.busy = 0
self.ftp = ftplib.FTP()
self.ftp.connect(self.host, self.port)
self.ftp.login(self.user, self.passwd)
@@ -504,6 +505,7 @@
self.ftp.cwd(dir)
def retrfile(self, file, type):
import ftplib
+ self.endtransfer()
if type in ('d', 'D'): cmd = 'TYPE A'; isdir = 1
else: cmd = 'TYPE ' + type; isdir = 0
try:
@@ -513,6 +515,13 @@
self.ftp.voidcmd(cmd)
conn = None
if file and not isdir:
+ # Use nlst to see if the file exists at all
+ try:
+ self.ftp.nlst(file)
+ except ftplib.error_perm, reason:
+ raise IOError, ('ftp error', reason), \
+ sys.exc_info()[2]
+ # Try to retrieve as a file
try:
cmd = 'RETR ' + file
conn = self.ftp.transfercmd(cmd)
@@ -525,13 +534,18 @@
if file: cmd = 'LIST ' + file
else: cmd = 'LIST'
conn = self.ftp.transfercmd(cmd)
+ self.busy = 1
return addclosehook(conn.makefile('rb'), self.endtransfer)
def endtransfer(self):
+ if not self.busy:
+ return
+ self.busy = 0
try:
self.ftp.voidresp()
except ftperrors():
pass
def close(self):
+ self.endtransfer()
try:
self.ftp.close()
except ftperrors():