smtplib, capturing output from set_debuglevel ??

[Andrew Dalke]

Tim Williams wrote:
> Can anyone suggest a way of capturing the output from smtplib's
> set_debuglevel  into a list or dictionary  (or anything else I can work
> with),

Looking at smtplib.py, all of the debug messages go to
the module variable 'stderr', which is a reference to sys.stderr.

That means you can replace smtplib.stderr  with something
of your own.  Try this untested bit of code

import cStringIO
old_error = smtplib.error
new_error = cStringIO.StringIO()
try:
   smtplib.error = new_error
    ... do your smtplib call here ...
finally:
   smtplib.error = old_error
   print "Debug messages"
   print new_error.getvalue()

What this does is replace smtplib.error with a StringIO,
which is a file-like object that stays in memory.  I used
the try/finally to ensure that the original error output
file is restored after the smtplib call ends.

There are other things you could do by making your own
sufficiently file-like object instead of using StringIO.
All it needs to do is implement the 'write' method.
But it may have to accumulate several writes before it
gets a full line.

class ShowWrites:
   def write(self, text):
     print "Got", repr(text)

To test it out, change my first example so it uses
ShowWrite instead of StringIO and get rid of the
last two lines

new_error = ShowWrite()

and get rid of these two lines

old_error = smtplib.error
new_error = ShowWrites()
try:
   smtplib.error = new_error
    ... do your smtplib call here ...
finally:
   smtplib.error = old_error



				Andrew
				dalke at dalkescientific.com