Entry

Debugging server Python scripts

Apr 10th, 2001 09:44
Engineer TCSI,

A handy thing is the ability to run a server Python script inside the 
debugger.  This can be done as follows.
If I have a module (unit) Xxx, and a function (or method) Yyy, first,
rename the real Yyy to be _Yyy.  Then, write the following:
def Yyy(*args):
        import pdb, sys
        g = sys.modules['Xxx'].__dict__ # Set globals to be module Xxx
        l = {'args' : args}                     # Make "args" visible to 
pdb
        pdb.run("res = apply(_Yyy, args)", g, l)
Then, run the TOM without the +w option.  This will fire off pdb using
stdin and stdout.  You can then step into the function _Yyy and debug at 
will.
Submitted by storey Wed Feb  3 11:45:20 PST 1999
Additional (slightly different) approach:
To run an embedded pdb, you need to add a few lines.  For example, for 
the Test method of fmtoCard in Topo, you do:
    def Test(*args):
       import sys, pdb
       g = sys.modules['Topo'].__dict__
       l = {'args':args}
       pdb.run("res = apply(fmtoCardMix.Test0, args)", g, l)
       return l['res']
    def Test0(self, ret)
        # The test method being debugged.
          ...
g is the globals, so that this runs in the global space of the module 
being debugged.  This needs to be named the correct name for your 
module.
l is the locals, to pass in the args, and get the result.  The 
invocation is done at global scope, not class scope, so you need to pass 
the full name from the module scope, which is <Class>.<Method>, in this 
case, fmtoCardMix.Test0.