HTML formatted traceback
I grew tired of scrolling down through the very long tracbacks to get
to the actual error, so I wrote a function that lets me skip
everything up to my handler function. While I was at it I figured I
may as well highlight the things I want to see to make the tracebacks
easier to read. When I was finished I liked it so much I had to share,
it would be nice if this found it's way into mod_python. To adapt it
for your purposes, change the condition func == 'handler' to something
else (you probably don't want to cut out the call to handler like me.)
Please excuse my lousy html, I wrote it to be small so it didn't
clutter up my source, I hate html in my python code. Feel free to
change whatever you like.
-Dan
import sys, os, re, traceback
re_traceback = re.compile(r'File (?Pfile[^]+?), line
(?Pline\d+?), in (?Pfunc.+?)\s+(?Pcontext.+?)$',
re.DOTALL | re.MULTILINE)
def get_formatted_traceback(req):
''' Returns an html formatted traceback for the exception. '''
req.content_type = 'text/html'
buf = ['!DOCTYPE HTML PUBLIC -//W3C//DTD HTML 4.01 Transitional//EN',
'http://www.w3.org/TR/html4/loose.dtd;',
'htmlhead',
'style type=text/css',
'b { color: navy }',
'strong { color: green }',
'.context { font-style: italic; margin-left: 30px }',
'.trace { margin: 10px }'
'span { font-weight: bold; color: blue }',
'/style',
'/headbody']
begin_trace = False
for e in traceback.format_exception(*sys.exc_info()):
m = re_traceback.search(e)
if m is not None:
path, line, func, context = m.group('file', 'line', 'func', 'context')
path, filename = os.path.split(path)
if begin_trace:
buf.append('divFile %s\b%s/b, line %s, in
strong%s/strong\r\ndiv class=context%s/div/div' \
% (path, filename, line, func, context))
else:
# Ignore the stuff up to and including the entry point of
the application at the call to handler
if func == 'handler': begin_trace = True
else:
if begin_trace: buf.append('/divspan%s/span' % e) #
Last Line (the error)
else: buf.append('%sdiv class=trace' % e) # First line (Traceback:)
buf.append('/body/html')
return '\r\n'.join(buf)
Re: HTML formatted traceback
Dan Eloff wrote .. I grew tired of scrolling down through the very long tracbacks to get to the actual error, so I wrote a function that lets me skip everything up to my handler function. While I was at it I figured I may as well highlight the things I want to see to make the tracebacks easier to read. When I was finished I liked it so much I had to share, it would be nice if this found it's way into mod_python. To adapt it for your purposes, change the condition func == 'handler' to something else (you probably don't want to cut out the call to handler like me.) Please excuse my lousy html, I wrote it to be small so it didn't clutter up my source, I hate html in my python code. Feel free to change whatever you like. I'll agree that mod_python 3.3 tracebacks are perhaps longer than they need to be given that I factored out various stuff into some functions so as to be able to reuse it across connection, handler and filter dispatch. I also like the idea of using colour to highlight important stuff. Thus, probably a good time to upgrade the standard traceback page that mod_python generates when there is an error. In others words, incorporate your ideas into the CallBack.ReportError function in the mod_python.apache module. When integrated, will have to be a bit more tricky to deal with fact that could be any phase and handler name for phase can be overridden. The information to do all that should be available though. Anyone else got any other ideas of what to put in the page? For example, perhaps stuff like what req.filename, req.path_info, req.uri etc are set to. Once we get a feel what would be good to see, I'll create a JIRA issue for it and reference the discussion in the mailing list archive. With all my talk of dependency graphs, am thinking I could also put that code in mod_python.testhandler module so as to be optionally used by people as an aid for debugging applications as well. Graham
Re: HTML formatted traceback
I'll agree that mod_python 3.3 tracebacks are perhaps longer than they need to be given that I factored out various stuff into some functions so as to be able to reuse it across connection, handler and filter dispatch. I also like the idea of using colour to highlight important stuff. Thus, probably a good time to upgrade the standard traceback page that mod_python generates when there is an error. In others words, incorporate your ideas into the CallBack.ReportError function in the mod_python.apache module. When integrated, will have to be a bit more tricky to deal with fact that could be any phase and handler name for phase can be overridden. The information to do all that should be available though. I'll get it working for regular handlers, and if the others are non-obvious I'll get help on this mailing list. Anyone else got any other ideas of what to put in the page? For example, perhaps stuff like what req.filename, req.path_info, req.uri etc are set to. That kind of thing should go below the traceback, so as to prevent the problem of having to scroll to see the error from being repeated. I wonder if it would be useful to present a formatted dump of lots of information in the req, server, connection objects. Once we get a feel what would be good to see, I'll create a JIRA issue for it and reference the discussion in the mailing list archive. With all my talk of dependency graphs, am thinking I could also put that code in mod_python.testhandler module so as to be optionally used by people as an aid for debugging applications as well. Yes, good idea. -Dan
