Gut (and purge) the anemic 'debug' module

* lib/common.py
  (print_exception_data): Was debug.PrintException().
  (get_exception_data): Was debug.GetExceptionData().

* lib/viewvc.py
  (): Track renamed/relocated methods.
  (download_tarball): Implement the tarball debugging stuff using a
    local variable instead of referring to something in the
    (now-removed) debug.py module.

* lib/debug.py
  Remove now-empty module.

* notes/HACKING.md
  Lose reference to the debug module.

lib/common.py

@@ -14,6 +14,8 @@
 #
 # -----------------------------------------------------------------------
 
+import sys
+
 # Special type indicators for diff header processing and idiff return codes
 _RCSDIFF_IS_BINARY = 'binary-diff'
 _RCSDIFF_ERROR = 'error'
@@ -72,3 +74,57 @@ def __str__(self):
  if self.status:
  return '%s: %s' % (self.status, self.msg)
  return "ViewVC Unrecoverable Error: %s" % self.msg
+
+
+def print_exception_data(server, exc_data):
+ status = exc_data['status']
+ msg = exc_data['msg']
+ tb = exc_data['stacktrace']
+
+ server.header(status=status)
+ server.write(b"<h3>An Exception Has Occurred</h3>\n")
+
+ s = ''
+ if msg:
+ s = '<p><pre>%s</pre></p>' % server.escape(msg)
+ if status:
+ s = s + ('<h4>HTTP Response Status</h4>\n<p><pre>\n%s</pre></p><hr />\n'
+ % status)
+ s = s.encode('utf-8', 'xmlcharrefreplace')
+ server.write(s)
+
+ server.write(b"<h4>Python Traceback</h4>\n<p><pre>")
+ server.write(server.escape(tb).encode('utf-8', 'xmlcharrefreplace'))
+ server.write(b"</pre></p>\n")
+
+
+def get_exception_data():
+ # Capture the exception before doing anything else.
+ exc_type, exc, exc_tb = sys.exc_info()
+
+ exc_dict = {
+ 'status' : None,
+ 'msg' : None,
+ 'stacktrace' : None,
+ }
+
+ try:
+ # Build a string from the formatted exception, but skipping the
+ # first line.
+ import traceback
+ if isinstance(exc, ViewVCException):
+ exc_dict['msg'] = exc.msg
+ exc_dict['status'] = exc.status
+ formatted = traceback.format_exception(exc_type, exc, exc_tb)
+ if exc_tb is not None:
+ formatted = formatted[1:]
+ exc_dict['stacktrace'] = ''.join(formatted)
+ finally:
+ # Prevent circular reference. The documentation for sys.exc_info
+ # warns "Assigning the traceback return value to a local variable
+ # in a function that is handling an exception will cause a
+ # circular reference..." This is all based on 'exc_tb', and we're
+ # now done with it, so toss it.
+ del exc_tb
+
+ return exc_dict

lib/viewvc.py

@@ -17,10 +17,7 @@
 
 __version__ = '1.3.0-dev'
 
-# this comes from our library; measure the startup time
-import debug
-
-# standard modules that we know are in the path or builtin
+# Standard modules that we know are in the path or builtin.
 import sys
 import os
 import calendar
@@ -41,8 +38,9 @@
 import subprocess
 
 # These modules come from our library (the stub has set up the path)
-from common import (ViewVCException, TemplateData, _item, _RCSDIFF_NO_CHANGES,
- _RCSDIFF_IS_BINARY, _RCSDIFF_ERROR)
+from common import (ViewVCException, get_exception_data, print_exception_data,
+ _RCSDIFF_NO_CHANGES, _RCSDIFF_IS_BINARY, _RCSDIFF_ERROR,
+ TemplateData, _item)
 import accept
 import config
 import ezt
@@ -4121,12 +4119,18 @@ def download_tarball(request):
  raise ViewVCException('Tarball generation is disabled',
  '403 Forbidden')
 
- # If debugging, we just need to open up the specified tar path for
- # writing. Otherwise, we get a writeable server output stream --
- # disabling any default compression thereupon -- and wrap that in
- # our own gzip stream wrapper.
- if debug.TARFILE_PATH:
- fp = open(debug.TARFILE_PATH, 'wb')
+ # Set DEBUG_TARFILE_PATH to a server-local path to enable tarball
+ # generation debugging and cause ViewVC to write the generated
+ # tarball (minus the compression layer) to that server filesystem
+ # location. This is *NOT* suitable for production environments!
+ #
+ # Otherwise, we do tarball generation as usual by getting a
+ # writeable server output stream -- disabling any default
+ # compression thereupon -- and wrapping that in our own gzip stream
+ # wrapper.
+ DEBUG_TARFILE_PATH = None
+ if DEBUG_TARFILE_PATH is not None:
+ fp = open(DEBUG_TARFILE_PATH, 'wb')
  else:
  tarfile = request.rootname
  if request.path_parts:
@@ -4145,14 +4149,14 @@ def download_tarball(request):
  fp.write(b'\0' * 1024)
  fp.close()
 
- if debug.TARFILE_PATH:
+ if DEBUG_TARFILE_PATH:
  request.server.header('')
  print("""
 <html>
 <body>
 <p>Tarball '%s' successfully generated!</p>
 </body>
-</html>""" % (debug.TARFILE_PATH))
+</html>""" % (DEBUG_TARFILE_PATH))
 
 
 def view_revision(request):
@@ -5176,7 +5180,7 @@ def load_config(pathname=None, server=None):
 
 
 def view_error(server, cfg):
- exc_dict = debug.GetExceptionData()
+ exc_dict = get_exception_data()
  status = exc_dict['status']
  if exc_dict['msg']:
  exc_dict['msg'] = server.escape(exc_dict['msg'])
@@ -5195,7 +5199,7 @@ def view_error(server, cfg):
 
  # Fallback to the old exception printer if no configuration is
  # available, or if something went wrong.
- debug.PrintException(server, exc_dict)
+ print_exception_data(server, exc_dict)
 
 def main(server, cfg):
  try:

notes/HACKING.md

@@ -71,9 +71,6 @@ new features require modifications to the [ViewVC URL
 schema](./docs/url-reference.html), make sure those modifications
 preserve the existing functionality of all ViewVC URLs.
 
-The `lib` subdirectory contains a module `debug.py` which you may find
-useful for performance testing.
-
 If a new file or module is added, a new line in the installer program
 `viewvc-install` is required.