Rewrite the Connection class to (hopefully) fix known problems with

SMTP_MAX_SESSIONS_PER_CONNECTION not being honored and connection
problems in the middle of a session not being properly recovered.

Closing SF bug #707624, although I implemented this in a different
way.

1 files changed, 13 insertions, 9 deletions

diff --git a/Mailman/Handlers/SMTPDirect.py b/Mailman/Handlers/SMTPDirect.py
index 4724c3a18..da7e3eb2f 100644
--- a/Mailman/Handlers/SMTPDirect.py
+++ b/Mailman/Handlers/SMTPDirect.py
@@ -50,7 +50,7 @@ DOT = '.'
 # Manage a connection to the SMTP server
 class Connection:
     def __init__(self):
-        self.__connect()
+        self.__conn = None
 
     def __connect(self):
         self.__conn = smtplib.SMTP()
@@ -58,26 +58,30 @@ class Connection:
         self.__numsessions = mm_cfg.SMTP_MAX_SESSIONS_PER_CONNECTION
 
     def sendmail(self, envsender, recips, msgtext):
+        if self.__conn is None:
+            self.__connect()
         try:
             results = self.__conn.sendmail(envsender, recips, msgtext)
         except smtplib.SMTPException:
-            # For safety, reconnect
-            self.__conn.quit()
-            self.__connect()
-            # Let exceptions percolate up
+            # For safety, close this connection.  The next send attempt will
+            # automatically re-open it.  Pass the exception on up.
+            self.quit()
             raise
-        # Decrement the session counter, reconnecting if necessary
+        # This session has been successfully completed.
         self.__numsessions -= 1
         # By testing exactly for equality to 0, we automatically handle the
         # case for SMTP_MAX_SESSIONS_PER_CONNECTION <= 0 meaning never close
         # the connection.  We won't worry about wraparound <wink>.
         if self.__numsessions == 0:
-            self.__conn.quit()
-            self.__connect()
+            self.quit()
         return results
 
     def quit(self):
-        self.__conn.quit()
+        try:
+            self.__conn.quit()
+        except smtplib.SMTPException:
+            pass
+        self.__conn = None