Generic expat-based XML parser base class.

lib/python/TAL/XMLParser.py

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+##############################################################################
+"""
+Generic expat-based XML parser base class.
+"""
+
+import sys
+
+class XMLParser:
+
+    ordered_attributes = 0
+
+    handler_names = [
+        "StartElementHandler",
+        "EndElementHandler",
+        "ProcessingInstructionHandler",
+        "CharacterDataHandler",
+        "UnparsedEntityDeclHandler",
+        "NotationDeclHandler",
+        "StartNamespaceDeclHandler",
+        "EndNamespaceDeclHandler",
+        "CommentHandler",
+        "StartCdataSectionHandler",
+        "EndCdataSectionHandler",
+        "DefaultHandler",
+        "DefaultHandlerExpand",
+        "NotStandaloneHandler",
+        "ExternalEntityRefHandler",
+        "XmlDeclHandler",
+        "ElementDeclHandler",
+        "AttlistDeclHandler"
+        ]
+
+    def __init__(self, encoding=None):
+        self.parser = p = self.createParser()
+        if self.ordered_attributes:
+            try:
+                self.parser.ordered_attributes = self.ordered_attributes
+            except AttributeError:
+                sys.stderr.write("Can't set ordered_attributes\n")
+                self.ordered_attributes = 0
+        for name in self.handler_names:
+            method = getattr(self, name, None)
+            if method is not None:
+                try:
+                    setattr(p, name, method)
+                except AttributeError:
+                    sys.stderr.write("Can't set expat handler %s\n" % name)
+
+    def createParser(self, encoding=None):
+        try:
+            from Products.ParsedXML.Expat import pyexpat
+            return pyexpat.ParserCreate(encoding, ' ')
+        except ImportError:
+            from xml.parsers import expat
+            return expat.ParserCreate(encoding, ' ')
+
+    def parseFile(self, filename):
+        self.parseStream(open(filename))
+
+    def parseString(self, s):
+        from cStringIO import cStringIO
+        self.ParseStream(cStringIO(s))
+
+    def parseURL(self, url):
+        import urllib
+        self.parseStream(urllib.urlopen(url))
+
+    def parseStream(self, stream):
+        self.parser.ParseFile(stream)