Viewing file:  namespace.py (4.73 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
"""
A parser filter for namespace support. Placed externally to the parser
for efficiency reasons.
$Id: namespace.py,v 1.5 2001/12/30 12:09:14 loewis Exp $
"""
import string
import xmlapp
# --- ParserFilter
class ParserFilter(xmlapp.Application):
"A generic parser filter class."
def __init__(self):
xmlapp.Application.__init__(self)
self.app=xmlapp.Application()
def set_application(self,app):
"Sets the application to report events to."
self.app=app
# --- Methods inherited from xmlapp.Application
def set_locator(self,locator):
xmlapp.Application.set_locator(self,locator)
self.app.set_locator(locator)
def doc_start(self):
self.app.doc_start()
def doc_end(self):
self.app.doc_end()
def handle_comment(self,data):
self.app.handle_comment(data)
def handle_start_tag(self,name,attrs):
self.app.handle_start_tag(name,attrs)
def handle_end_tag(self,name):
self.app.handle_end_tag(name)
def handle_data(self,data,start,end):
self.app.handle_data(data,start,end)
def handle_ignorable_data(self,data,start,end):
self.app.handle_ignorable_data(data,start,end)
def handle_pi(self,target,data):
self.app.handle_pi(target,data)
def handle_doctype(self,root,pubID,sysID):
self.app.handle_doctype(root,pubID,sysID)
def set_entity_info(self,xmlver,enc,sddecl):
self.app.set_entity_info(xmlver,enc,sddecl)
# --- NamespaceFilter
class NamespaceFilter(ParserFilter):
"""An xmlproc application that processes qualified names and reports them
as 'URI local-part' names. It reports errors through the error reporting
mechanisms of the parser."""
def __init__(self,parser):
ParserFilter.__init__(self)
self.ns_map={} # Current prefix -> URI map
self.ns_stack=[] # Pushed for each element, used to maint ns_map
self.rep_ns_attrs=0 # Report xmlns-attributes?
self.parser=parser
def set_report_ns_attributes(self,action):
"Tells the filter whether to report or delete xmlns-attributes."
self.rep_ns_attrs=action
# --- Overridden event methods
def handle_start_tag(self,name,attrs):
old_ns={} # Reset ns_map to these values when we leave this element
del_ns=[] # Delete these prefixes from ns_map when we leave element
# attrs=attrs.copy() Will have to do this if more filters are made
# Find declarations, update self.ns_map and self.ns_stack
for (a,v) in attrs.items():
if a[:6]=="xmlns:":
prefix=a[6:]
if string.find(prefix,":")!=-1:
self.parser.report_error(1900)
if v=="":
self.parser.report_error(1901)
elif a=="xmlns":
prefix=""
else:
continue
if self.ns_map.has_key(prefix):
old_ns[prefix]=self.ns_map[prefix]
else:
del_ns.append(prefix)
if prefix=="" and v=="":
del self.ns_map[prefix]
else:
self.ns_map[prefix]=v
if not self.rep_ns_attrs:
del attrs[a]
self.ns_stack.append((old_ns,del_ns))
# Process elem and attr names
name=self.__process_name(name)
parts=string.split(name)
if len(parts)>1:
ns=parts[0]
else:
ns=None
for (a,v) in attrs.items():
del attrs[a]
aname=self.__process_name(a,ns)
if attrs.has_key(aname):
self.parser.report_error(1903)
attrs[aname]=v
# Report event
self.app.handle_start_tag(name,attrs)
def handle_end_tag(self,name):
name=self.__process_name(name)
# Clean up self.ns_map and self.ns_stack
(old_ns,del_ns)=self.ns_stack[-1]
del self.ns_stack[-1]
self.ns_map.update(old_ns)
for prefix in del_ns:
del self.ns_map[prefix]
self.app.handle_end_tag(name)
# --- Internal methods
def __process_name(self,name,default_to=None):
n=string.split(name,":")
if len(n)>2:
self.parser.report_error(1900)
return name
elif len(n)==2:
if n[0]=="xmlns":
return name
try:
return "%s %s" % (self.ns_map[n[0]],n[1])
except KeyError:
self.parser.report_error(1902)
return name
elif default_to!=None:
return "%s %s" % (default_to,name)
elif self.ns_map.has_key("") and name!="xmlns":
return "%s %s" % (self.ns_map[""],name)
else:
return name
|