I personally like the idea of locking the files more than I like the idea of a daemon delivering queued mail because there will always be the worry that something accidentally kills the daemon process while no admin is around.

Lock timeouts sound like a good solution and are already available in the file locking module.

scott

On Sat, Sep 26, 1998 at 09:38:30PM +0200, Dan Ohnesorg, admin of POWER wrote: | On 25 Sep 98, at 16:16, The Dragon De Monsyne wrote: | | > On Fri, 25 Sep 1998, Dan Ohnesorg, admin of POWER wrote: | > | > > I become sometimes irriting error messages cannot unlink....... by | > > queue processing. So I sugest this modification of dequeue | > > function | > > | > > def dequeueMessage(msg): | > > import os | > > try: | > > os.unlink(msg) | > > except: | > > from Logging.StampedLogger import StampedLogger | > > l = StampedLogger("queue", "DequeueMessage", immediate=1) | > > l.write("Cannot remove:\t %s\n" % msg) | > > l.flush()
| > > | > > I currently dont know why this error happens, I still searching. | > | > Oh, I know why this happens. It's related to the duplicate | > delivery problem. Another proccess has delivered the queued message out | > from under the first one. (and deleted the queue file, which is why the | > first process cannot delete the message. ) | | Yes so it is probably done, but I think some messages, which are | afected with this error aren't send duplicate. | | | > | > I've actually fixed this problem, by the simple expediant of | > making all of the Mailman programs simply queue, and not try to deliver, | > outgoing messages. Then I have a modified run_queue program that runs | > continuously, de-queueing and delivering messages. Works great, sofar. | > If anyone's interested in the diffs. let me know. (I mentioned | > this whence I first did this, bout a month ago, but noone seemed | > interested then. ) | | Send me this, please, but I am working on another sugestion. I | will made this: when one process begins with delivery, it makes | lock file mm_l.1 and so on. Locked files are skipped by another | processes. Sucessfull delivery removes both lock and data files, | unsuccesfull only lock file. | Danger on my solution is, that when mailman dies, the file is | locked forever (or probalby I can delete lock files older than X | from crond). | | Some opinion to this? | | cheers | dan | | ________________________________________ | DDDDDD
| DD DD Dan Ohnesorg, supervisor on POWER
| DD OOOO Dan@feld.cvut.cz | DD OODDOO Dep. of Power Engineering | DDDDDD OO CTU FEL Prague, Bohemia | OO OO work: +420 2 24352785;+420 2 24972109 | OOOO home: +420 311 679679;+420 311 679311 | ________________________________________ | Pesimista vidi v ementalskem syru jen ty diry. | | | _______________________________________________ | Mailman-Developers maillist - Mailman-Developers@python.org | http://www.python.org/mailman/listinfo/mailman-developers |

On 26 Sep 98, at 18:02, Scott wrote:

I personally like the idea of locking the files more than I like the idea of a daemon delivering queued mail because there will always be the worry that something accidentally kills the daemon process while no admin is around.

Lock timeouts sound like a good solution and are already available in the file locking module.

So I have made it as follows. I haven't used flock module, becouse I think it is not good for this situacion. We can use it when there is reorganized code in Utis and OutgoinQueue, so it is too distributed. I haven't made backup before modifing my copy, so I cannot send diffs. My mailman is very different from oficial becouse it containst features like DSN, administrativ via filter, character set conversion .... and so I cannot made diff to clean distribution.

Modification is very short. First in Utils.py

in def TrySMTPDelivery(recipient, sender, text, queue_entry): is on end added

if failure:
    from Logging.StampedLogger import StampedLogger
    l = StampedLogger("smtp-failures", "TrySMTPDelivery", immediate=1)
    l.write("To %s:\n" % recipient)
    l.write("\t %s / %s\n" % (failure[0], failure[1]))
    l.flush()

•    import os, re

•    lock = re.sub('mm_q\.','mm_l\.',queue_entry)

•    os.unlink(lock)

And in OutgoingQueue

def dequeueMessage(msg):

• import os, re
• lock = re.sub('mm_q\.','mm_l\.',msg) try: os.unlink(msg)

• os.unlink(lock)

  except: from Logging.StampedLogger import StampedLogger l = StampedLogger("queue", "DequeueMessage", immediate=1) l.write("Cannot remove:\t %s\n" % msg) l.flush()

def processQueue():

• import os, re files = os.listdir(mm_cfg.DATA_DIR) for file in files: if TEMPLATE <> file[:len(TEMPLATE)]: continue full_fname = os.path.join(mm_cfg.DATA_DIR, file)

•    lock = re.sub('mm_q\.','mm_l\.',full_fname)

•    existence = os.stat(lock)

•    if not(S_ISREG(existence)):

•      continue

•    l = open(lock,"a+")

•    l.write(os.getpid()) 

•    l.close()
    f = open(full_fname,"r")
    recip,sender,text = marshal.load(f)
    f.close()
    import Utils
    Utils.TrySMTPDelivery(recip,sender,text,full_fname)
  
                ________________________________________

  DDDDDD
  DD DD Dan Ohnesorg, supervisor on POWER
  DD OOOO Dan@feld.cvut.cz DD OODDOO Dep. of Power Engineering DDDDDD OO CTU FEL Prague, Bohemia OO OO work: +420 2 24352785;+420 2 24972109 OOOO home: +420 311 679679;+420 311 679311 ________________________________________ Neodkladej na zitrek, co dnes mohou udelat jini.