Changing class name causes process to 'hang'

[Tim Johnson]

* Tim Johnson <tim at johnsons-web.com> [110313 08:27]:
>   One other thing I just realized:
>   The process stops inside of a function call to another object
>   method, if that method call is removed, the process teminates.
>   :) I may have a solution later today, and will relay it to you if
>   found. Must have coffee first.
  I've had coffee, and also I've eaten a bit of crow. If I had no
  dignity to spare I might have dropped this thread after the last
  post, but I owe it to those who might come after me to explain
  what happened. If I have any excuse, it is that I wrote this code
  when I had about a month of python experience.
  So here we go... 
  The cleanup part is to write a logfile. The logfile is written by
  the write() method of a log object. The method was coded to accept
  any number of data types and execute based on the type from an
  if/elif/else code block. The cgi object was passed to the method.
  The original code follows:
  ## code begins
  		if type(args) == type({}): ## it's a dictionary
			args['time_date_stamp'] = '%s%d' % (std.local_time(),std.randomize(8))
			keys = args.keys()
			keys.sort()
			for key in keys:
				outfile.write('\t%s: %s\n' % (key,args[key]))
		elif type(args) == type(''):
			outfile.write('%s\n%s\n' % (std.local_time(),args))
		elif std.IsCgiObj(args):   ## dump the cgi object 
			dump = args.getEnv('time_date_stamp=%s' % (std.local_time()))
			for line in dump:
				outfile.write('  %s\n' % line)
		else : ## default = it's a list
			if args:
				outfile.write('time_date_stamp=%s\n' % (std.local_time()))
				for arg in args:
					outfile.write('  %s\n' % arg)
  ## /code ends
I did two obvious things wrong here:
First of all, std.IsCgiObj() returned false when I changed
the class name because std.IsCgiObj() tested for an explicit
match of 'cgitools' with the objects __class__.__name__ member.

Secondly, and worse, the default of the test block was an assumption
and I did not test the assumption. Bad, bad, very bad!
Therefore my code attempted to process the object as a list and down
the Rabit Hole we went. And I ended up with some *really* big
logfiles :).

Following is a tentative revision:
  ## code begins
		elif 'instance' in (str(type(args))):   ## it's an object
			if hasattr(args,'getEnv'): ## test for method
				dump = args.getEnv('time_date_stamp=%s' % (std.local_time()))
				for line in dump:
					outfile.write('  %s\n' % line)
			else :
				erh.Report("object passed to logger.write() must have a `getEnv()' method" )
		else : ## it's a list
			if type(args) != []:  ## make no assumptions
				erh.Report('List expected in default condition of logger.write()')
			if args:
				outfile.write('time_date_stamp=%s\n' % (std.local_time()))
				for arg in args:
					outfile.write('  %s\n' % arg)
  ## /code ends
  ## erh.Report() writes a messages and aborts process.
Of course, I could have problems with an object with a
malfunctioning getEnv() method, so I'll have to chew that one over
for a while.
I appreciate Terry's help. I'd welcome any other comments. I'm
also researching the use of __class__.__name__. One of my questions
is: can the implementation of an internal like __class__.__name__
change in the future?

-- 
Tim 
tim at johnsons-web.com or akwebsoft.com
http://www.akwebsoft.com