Changing the name of a compressed file

[Aki Tuomi]

There is global mail_plugins variable, you just have to be careful not to overwrite it somewhere.

Aki

> On June 11, 2017 at 2:46 PM Peter West <lists at pbw.id.au> wrote:
> 
> 
> It looks as though there is no global mail_plugins variable.  Is this the case?  Or have I misunderstood how global variable are expressed?
> 
> P
> 
> > On 10 Jun 2017, at 9:10 pm, Peter West <lists at pbw.id.au> wrote:
> > 
> > Ok, I added zlib to imap protocol.
> > 
> > protocol imap {
> >  …
> >  mail_plugins = $mail_plugins zlib
> > }
> > 
> > Now both imap and lmtp protocols have zlib plugin enabled, and both send and receive mail is compressed.
> > 
> > Peter
> > 
> >> On 10 Jun 2017, at 6:50 pm, Aki Tuomi <aki.tuomi at dovecot.fi> wrote:
> >> 
> >> Please check that you are not overwriting mail plugins for lmtp. Or post your doveconf -n.
> >> 
> >> Aki
> >> 
> >>> On June 10, 2017 at 11:10 AM Peter West <lists at pbw.id.au> wrote:
> >>> 
> >>> 
> >>> Not sure what you mean. I’m using lmtp to send messages to Dovecot from Postfix.
> >>> 
> >>>> On 10 Jun 2017, at 6:08 pm, Aki Tuomi <aki.tuomi at dovecot.fi> wrote:
> >>>> 
> >>>> What's your LDA?
> >>>> 
> >>>> Aki
> >>>> 
> >>>>> On June 10, 2017 at 11:01 AM Peter West <lists at pbw.id.au> wrote:
> >>>>> 
> >>>>> 
> >>>>> Thanks for that Aki.
> >>>>> 
> >>>>> Follow-up question.  I tried to initiate compression by adding
> >>>>> 
> >>>>> mail_plugins = $mail_plugins zlib
> >>>>> 
> >>>>> plugin {
> >>>>>  zlib_save_level = 6
> >>>>>  zlib_save = xz
> >>>>> }
> >>>>> 
> >>>>> 
> >>>>> to dovecot.conf.  I restarted dovecot and sent one message to the server, and one message from the server.  Neither was compressed.  I changed the save type to
> >>>>> 
> >>>>>  zlib_save = bz2
> >>>>> 
> >>>>> and repeated. This time the message received (in /var/vmail/<host>/<username>/cur) was not compressed, but the message in /var/vmail/<host>/<username>/.Sent/cur was bzip2 compressed.
> >>>>> 
> >>>>> Why is the received mail not being compressed?  Is this the point of the discussion about compressing old mails?
> >>>>> 
> >>>>> 
> >>>>>> On 10 Jun 2017, at 4:43 pm, Aki Tuomi <aki.tuomi at dovecot.fi> wrote:
> >>>>>> 
> >>>>>> 
> >>>>>>> On June 10, 2017 at 5:58 AM Peter West <lists at pbw.id.au> wrote:
> >>>>>>> 
> >>>>>>> 
> >>>>>>> Concerning Maildir, the wiki page on compression has this:
> >>>>>>> 
> >>>>>>> All mails must have ,S=<size> in their filename where <size> contains the original uncompressed mail size, otherwise there will be problems with quota calculation as well as other potential random failures. Note that if the filename doesn’t contain the ,S=<size> before compression, adding it afterwards changes the base filename and thus the message UID. The safest thing to do is simply to not compress such files.
> >>>>>>> 
> >>>>>>> Further down on the same page is this:
> >>>>>>> 
> >>>>>>> If the file does exist, rename() (mv) the compressed file over the original file.
> >>>>>>> 	• Dovecot can now read the file, but to avoid compressing it again on the next run, you'll probably want to rename it again to include e.g. a "Z" flag in the file name to mark that it was compressed (e.g. 1223212411.M907959P17184.host,S=3271:2,SZ).
> >>>>>>> 
> >>>>>>> These comments seem to contradict each. Or is there a difference between adding the size specifier to the filename and adding a Z flag to the end of the file name?
> >>>>>>> 
> >>>>>>> --
> >>>>>>> Peter West
> >>>>>>> pbw at pbw.id.au
> >>>>>>> And the great throng heard him gladly.
> >>>>>>> 
> >>>>>> 
> >>>>>> Keyword is 'base filename'. From the wiki, "The standard filename definition is: "<base filename>:2,<flags>".". Z is a flag.
> >>>>>> 
> >>>>>> Aki
> >>>>> 
> >>> 
> > 
>