"""Exception and error handling.
This contains the core exceptions that the implementations should raise
as well as the IActiveScriptError interface code.
"""
import sys, traceback
from win32com.axscript import axscript
import winerror
import win32com.server.exception
import win32com.server.util
import pythoncom
import re
debugging = 0
def FormatForAX(text):
"""Format a string suitable for an AX Host
"""
# Replace all " with ', so it works OK in HTML (ie, ASP)
return ExpandTabs(AddCR(text))
def ExpandTabs(text):
return re.sub('\t',' ', text)
def AddCR(text):
return re.sub('\n','\r\n',text)
class IActiveScriptError:
"""An implementation of IActiveScriptError
The ActiveX Scripting host calls this client whenever we report
an exception to it. This interface provides the exception details
for the host to report to the user.
"""
_com_interfaces_ = [axscript.IID_IActiveScriptError]
_public_methods_ = ["GetSourceLineText","GetSourcePosition","GetExceptionInfo"]
def _query_interface_(self, iid):
print "IActiveScriptError QI - unknown IID", iid
return 0
def _SetExceptionInfo(self, exc):
self.exception = exc
def GetSourceLineText(self):
return self.exception.linetext
def GetSourcePosition(self):
ctx = self.exception.sourceContext
# Zero based in the debugger (but our columns are too!)
return ctx, self.exception.lineno + self.exception.startLineNo-1, self.exception.colno
def GetExceptionInfo(self):
return self.exception
class AXScriptException(win32com.server.exception.COMException):
"""A class used as a COM exception.
Note this has attributes which conform to the standard attributes
for COM exceptions, plus a few others specific to our IActiveScriptError
object.
"""
def __init__(self, site, codeBlock, exc_type, exc_value, exc_traceback):
# set properties base class shares via base ctor...
win32com.server.exception.COMException.__init__( self, \
description = "Unknown Exception", \
scode = winerror.DISP_E_EXCEPTION, \
source = "Python ActiveX Scripting Engine",
)
# And my other values...
if codeBlock is None:
self.sourceContext = 0
self.startLineNo = 0
else:
self.sourceContext = codeBlock.sourceContextCookie
self.startLineNo = codeBlock.startLineNumber
self.linetext = ""
self.__BuildFromException(site, exc_type, exc_value, exc_traceback)
def __BuildFromException(self, site, type , value, tb):
if debugging:
import linecache
linecache.clearcache()
try:
if issubclass(type, SyntaxError):
self._BuildFromSyntaxError(site, value, tb)
else:
self._BuildFromOther(site, type, value, tb)
except: # Error extracting traceback info!!!
traceback.print_exc()
# re-raise.
raise
def _BuildFromSyntaxError(self, site, value, tb):
# All syntax errors should have a message as element 0
try:
msg = value[0]
except:
msg = "Unknown Error (%s)" % (value,)
try:
(filename, lineno, offset, line) = value[1]
# Some of these may be None, which upsets us!
if offset is None:
offset = 0
if line is None:
line = ""
except:
msg = "Unknown"
lineno = 0
offset = 0
line = "Unknown"
self.description=FormatForAX(msg)
self.lineno = lineno
self.colno = offset - 1
self.linetext = ExpandTabs(line.rstrip())
def _BuildFromOther(self, site, exc_type, value, tb):
self.colno = -1
self.lineno = 0
if debugging: # Full traceback if debugging.
list=traceback.format_exception(exc_type, value, tb)
self.description = ExpandTabs(''.join(list))
return
# Run down the traceback list, looking for the first "<Script..>"
# Hide traceback above this. In addition, keep going down
# looking for a "_*_" attribute, and below hide these also.
hide_names = ["r_import","r_reload","r_open"] # hide from these functions down in the traceback.
depth = None
tb_top = tb
while tb_top:
filename, lineno, name, line = self.ExtractTracebackInfo(tb_top, site)
if filename[:7]=="<Script":
break
tb_top = tb_top.tb_next
format_items = []
if tb_top: # found one.
depth = 0
tb_look = tb_top
# Look down for our bottom
while tb_look:
filename, lineno, name, line = self.ExtractTracebackInfo(tb_look, site)
if name in hide_names:
break
# We can report a line-number, but not a filename. Therefore,
# we return the last line-number we find in one of our script
# blocks.
if filename.startswith("<Script"):
self.lineno = lineno
self.linetext = line
format_items.append((filename, lineno, name, line))
depth = depth + 1
tb_look = tb_look.tb_next
else:
depth = None
tb_top = tb
bits = ['Traceback (most recent call last):\n']
bits.extend(traceback.format_list(format_items))
if exc_type==pythoncom.com_error:
desc = "%s (0x%x)" % (value[1], value[0])
if value[0]==winerror.DISP_E_EXCEPTION and value[2] and value[2][2]:
desc = value[2][2]
bits.append("COM Error: "+desc)
else:
bits.extend(traceback.format_exception_only(exc_type, value))
# XXX - this utf8 encoding seems bogus. From well before py3k,
# we had the comment:
# > all items in the list are utf8 courtesy of Python magically
# > converting unicode to utf8 before compilation.
# but that is likely just confusion from early unicode days;
# Python isn't doing it, pywin32 probably was, so 'mbcs' would
# be the default encoding. We should never hit this these days
# anyway, but on py3k, we *never* will, and str objects there
# don't have a decode method...
if sys.version_info < (3,):
for i in xrange(len(bits)):
if type(bits[i]) is str:
#assert type(bits[i]) is str, type(bits[i])
bits[i] = bits[i].decode('utf8')
self.description = ExpandTabs(u''.join(bits))
# Clear tracebacks etc.
tb = tb_top = tb_look = None
def ExtractTracebackInfo(self, tb, site):
import linecache
f = tb.tb_frame
lineno = tb.tb_lineno
co = f.f_code
filename = co.co_filename
name = co.co_name
line = linecache.getline(filename, lineno)
if not line:
try:
codeBlock = site.scriptCodeBlocks[filename]
except KeyError:
codeBlock = None
if codeBlock:
# Note: 'line' will now be unicode.
line = codeBlock.GetLineNo(lineno)
if line:
line = line.strip()
else:
line = None
return filename, lineno, name, line
def __repr__(self):
return "AXScriptException Object with description:" + self.description
def ProcessAXScriptException(scriptingSite, debugManager, exceptionInstance):
"""General function to handle any exception in AX code
This function creates an instance of our IActiveScriptError interface, and
gives it to the host, along with out exception class. The host will
likely call back on the IActiveScriptError interface to get the source text
and other information not normally in COM exceptions.
"""
# traceback.print_exc()
instance = IActiveScriptError()
instance._SetExceptionInfo(exceptionInstance)
gateway = win32com.server.util.wrap(instance, axscript.IID_IActiveScriptError)
if debugManager:
fCallOnError = debugManager.HandleRuntimeError()
if not fCallOnError:
return None
try:
result = scriptingSite.OnScriptError(gateway)
except pythoncom.com_error, details:
print "**OnScriptError failed:", details
print "Exception description:'%s'" % (repr(exceptionInstance.description))
print "Exception text:'%s'" % (repr(exceptionInstance.linetext))
result = winerror.S_FALSE
if result==winerror.S_OK:
# If the above returns NOERROR, it is assumed the error has been
# correctly registered and the value SCRIPT_E_REPORTED is returned.
ret = win32com.server.exception.COMException(scode=axscript.SCRIPT_E_REPORTED)
return ret
else:
# The error is taken to be unreported and is propagated up the call stack
# via the IDispatch::Invoke's EXCEPINFO parameter (hr returned is DISP_E_EXCEPTION.
return exceptionInstance
|