Re: [Nmh-workers] Multi-homed postproc, v2

[Bob Carragher]

Thanks for the proposed localpostproc, Ken!

Unfortunately, I don't think I can use it, due to a lack of a
looping mechanism -- or, at least, a "there-exists" mechanism.
I need something that checks the recipients' host(s), which
means potentially checking more than 1 string.  The pseudo-code
would be roughly

     if @.*stanford.edu in {%(host{to}), %(host{cc}), %(host{bcc})}
         postflags=""
     else
         postflags="-server smtp.gmail.com -port submission -tls -sasl -user 
dnc2dnc"

I could break up the if-clause into 3 scan(1) invocations, but
things break down when there's more than 1 address in a given
component since, quoting from the mh-format(5) page:

     The return value of functions noted with `*' is computed
     from the first address present in the header component.

     [...]
     host        addr     string   the host domain*

Am I missing an obvious solution?

Thanks!

                                Bob

On Wed, 04 Mar 2015 12:25:41 -0500 Ken Hornstein <address@hidden> sez:

> So after testing it for a day, I found a problem.
> Specifically, if you're using annotations on replies my simple
> script broke.  The reason is that the arguments ended up being:
> 
>       [...] draft filename -idanno N
> 
> Where "N" was the file descriptor to write the annotation to;
> my previous iteration assumed the last argument to post was the
> filename.
> 
> I ended up having to do this code (complete script appended at
> the end):
> 
> find_draftmessage() {
>         skip_next=0
> 
>         for arg; do
>                 case "$arg" in
>                 -al* | -filt* | -wi* | -client | -idanno | -server | \
>                 -partno | -saslmaxssf | -saslmech | -user | -por* | \
>                 -file* | -mhl* | -mt* | -cr* | -lib* | -oauth)
>                         skip_next=1
>                         ;;
>                 -*)     skip_next=0;
>                         ;;
>                 *)
>                         if [ "$skip_next" -eq 0 ]; then
>                                 draftmessage="$arg"
>                                 return 0
>                         fi
>                         skip_next=0
>                         ;;
>                 esac
>         done
> 
>       echo "Cannot find draft message name in argument list"
>         exit 1
> }
> 
> I am just wondering out loud if there is a better way than
> putting knowledge in the script of whether a particular switch
> takes an argument.  It just seems brittle to me.  Ideas?  Other
> approaches?
> 
> --Ken
> 
> 
>
>
>
> #!/bin/sh
> #
> # localpostproc - decide where to send email based on the draft message
> #
> 
> #
> # Find out which message is the draft message; yes, this sucks
> #
> 
> find_draftmessage() {
>       skip_next=0
> 
>       for arg; do
>               case "$arg" in
>               -al* | -filt* | -wi* | -client | -idanno | -server | \
>               -partno | -saslmaxssf | -saslmech | -user | -por* | \
>               -file* | -mhl* | -mt* | -cr* | -lib* | -oauth)
>                       skip_next=1
>                       ;;
>               -*)     skip_next=0;
>                       ;;
>               *)
>                       if [ "$skip_next" -eq 0 ]; then
>                               draftmessage="$arg"
>                               return 0
>                       fi
>                       skip_next=0
>                       ;;
>               esac
>       done
> 
>       echo "Cannot find draft message name in argument list"
>       exit 1
> }
> 
> realpost="$(mhparam libdir)/post"
> 
> if [ $# -eq 0 ]; then
>       echo "Usage: [post switches] filename"
>       exit 1
> fi
> 
> find_draftmessage "$@"
> 
> fromhost=$(scan -format '%(host{from})' -file "$draftmessage")
> 
> if [ $? -ne 0 ]; then
>       echo "Unable to run scan on draft file $draftmessage, aborting"
>       exit 1
> fi
> 
> if [ -z "$fromhost" ]; then
>       echo "Could not determine hostname of From: address"
>       exit 1;
> fi
> 
> case "$fromhost" in
>       *.some.other.host)
>       postflags="-server some.other.server -sasl -port submission"
>       ;;
> 
>       pobox.com)
>       postflags="-server smtp.pobox.com -sasl -tls -port submission"
>       ;;
> 
>       *)
>       echo "Don't know how to send email from $fromhost"
>       exit 1
>       ;;
> esac
> 
> exec "$realpost" $postflags "$@"