import handler """An XML Reader is the SAX 2 name for an XML parser. XML Parsers should be based on this code. """ # ===== XMLREADER ===== class XMLReader: def __init__(self): self._cont_handler = handler.ContentHandler() #self._dtd_handler = handler.DTDHandler() #self._ent_handler = handler.EntityResolver() self._err_handler = handler.ErrorHandler() def parse(self, source): "Parse an XML document from a system identifier or an InputSource." raise NotImplementedError("This method must be implemented!") def getContentHandler(self): "Returns the current ContentHandler." return self._cont_handler def setContentHandler(self, handler): "Registers a new object to receive document content events." self._cont_handler = handler def getDTDHandler(self): "Returns the current DTD handler." return self._dtd_handler def setDTDHandler(self, handler): "Register an object to receive basic DTD-related events." self._dtd_handler = handler def getEntityResolver(self): "Returns the current EntityResolver." return self._ent_handler def setEntityResolver(self, resolver): "Register an object to resolve external entities." self._ent_handler = resolver def getErrorHandler(self): "Returns the current ErrorHandler." return self._err_handler def setErrorHandler(self, handler): "Register an object to receive error-message events." self._err_handler = handler def setLocale(self, locale): """Allow an application to set the locale for errors and warnings. SAX parsers are not required to provide localization for errors and warnings; if they cannot support the requested locale, however, they must throw a SAX exception. Applications may request a locale change in the middle of a parse.""" raise SAXNotSupportedException("Locale support not implemented") def getFeature(self, name): "Looks up and returns the state of a SAX2 feature." raise SAXNotRecognizedException("Feature '%s' not recognized" % name) def setFeature(self, name, state): "Sets the state of a SAX2 feature." raise SAXNotRecognizedException("Feature '%s' not recognized" % name) def getProperty(self, name): "Looks up and returns the value of a SAX2 property." raise SAXNotRecognizedException("Property '%s' not recognized" % name) def setProperty(self, name, value): "Sets the value of a SAX2 property." raise SAXNotRecognizedException("Property '%s' not recognized" % name) class IncrementalParser(XMLReader): """This interface adds three extra methods to the XMLReader interface that allow XML parsers to support incremental parsing. Support for this interface is optional, since not all underlying XML parsers support this functionality. When the parser is instantiated it is ready to begin accepting data from the feed method immediately. After parsing has been finished with a call to close the reset method must be called to make the parser ready to accept new data, either from feed or using the parse method. Note that these methods must _not_ be called during parsing, that is, after parse has been called and before it returns. By default, the class also implements the parse method of the XMLReader interface using the feed, close and reset methods of the IncrementalParser interface as a convenience to SAX 2.0 driver writers.""" def __init__(self, bufsize=2**16 ): self._bufsize=bufsize XMLReader.__init__( self ) def parse(self, source): self.prepareParser(source) #FIXME: do some type checking: could be already stream, URL or # filename inf=open( source ) buffer = inf.read(self._bufsize) while buffer != "": self.feed(buffer) buffer = inf.read(self._bufsize) self.close() self.reset() def feed(self, data): """This method gives the raw XML data in the data parameter to the parser and makes it parse the data, emitting the corresponding events. It is allowed for XML constructs to be split across several calls to feed. feed may raise SAXException.""" raise NotImplementedError("This method must be implemented!") def prepareParser(self, source): """This method is called by the parse implementation to allow the SAX 2.0 driver to prepare itself for parsing.""" raise NotImplementedError("prepareParser must be overridden!") def close(self): """This method is called when the entire XML document has been passed to the parser through the feed method, to notify the parser that there are no more data. This allows the parser to do the final checks on the document and empty the internal data buffer. The parser will not be ready to parse another document until the reset method has been called. close may raise SAXException.""" raise NotImplementedError("This method must be implemented!") def reset(self): """This method is called after close has been called to reset the parser so that it is ready to parse new documents. The results of calling parse or feed after close without calling reset are undefined.""" raise NotImplementedError("This method must be implemented!") # ===== LOCATOR ===== class Locator: """Interface for associating a SAX event with a document location. A locator object will return valid results only during calls to DocumentHandler methods; at any other time, the results are unpredictable.""" def getColumnNumber(self): "Return the column number where the current event ends." return -1 def getLineNumber(self): "Return the line number where the current event ends." return -1 def getPublicId(self): "Return the public identifier for the current event." return None def getSystemId(self): "Return the system identifier for the current event." return None # --- AttributesImpl class AttributesImpl: def __init__(self, attrs, rawnames): self._attrs = attrs self._rawnames = rawnames def getLength(self): return len(self._attrs) def getType(self, name): return "CDATA" def getValue(self, name): return self._attrs[name] def getValueByQName(self, name): return self._attrs[self._rawnames[name]] def getNameByQName(self, name): return self._rawnames[name] def getNames(self): return self._attrs.keys() def getQNames(self): return self._rawnames.keys() def __len__(self): return len(self._attrs) def __getitem__(self, name): return self._attrs[name] def keys(self): return self._attrs.keys() def has_key(self, name): return self._attrs.has_key(name) def get(self, name, alternative=None): return self._attrs.get(name, alternative) def copy(self): return self.__class__(self._attrs, self._rawnames) def items(self): return self._attrs.items() def values(self): return self._attrs.values() def _test(): XMLReader() IncrementalParser() Locator() AttributesImpl() if __name__=="__main__": _test()