an xml reader is the sax 2 name for an xml parser xml parsers should be based on this code from import handler from exceptions import saxnotsupportedexception saxnotrecognizedexception xmlreader class xmlreader 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 raise a sax exception applications may request a locale change in the middle of a parse raise saxnotsupportedexceptionlocale support not implemented def getfeatureself name looks up and returns the state of a sax2 feature raise saxnotrecognizedexceptionfeature s not recognized name def setfeatureself name state sets the state of a sax2 feature raise saxnotrecognizedexceptionfeature s not recognized name def getpropertyself name looks up and returns the value of a sax2 property raise saxnotrecognizedexceptionproperty s not recognized name def setpropertyself name value sets the value of a sax2 property raise saxnotrecognizedexceptionproperty s not recognized name class incrementalparserxmlreader 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 notimplementederrorthis method must be implemented def prepareparserself source 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 notimplementederrorthis method must be implemented def resetself 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 getcolumnnumberself return the column number where the current event ends return 1 def getlinenumberself return the line number where the current event ends return 1 def getpublicidself return the public identifier for the current event return none def getsystemidself return the system identifier for the current event return none inputsource class inputsource sets the character encoding of this inputsource the encoding must be a string acceptable for an xml encoding declaration see section 4 3 3 of the xml recommendation the encoding attribute of the inputsource is ignored if the inputsource also contains a character stream self encoding encoding def getencodingself get the character encoding of this inputsource return self encoding def setbytestreamself bytefile get the byte stream for this input source the getencoding method will return the character encoding for this byte stream or none if unknown return self bytefile def setcharacterstreamself charfile attributesimpl nonnsaware implementation attrs should be of the form name value self attrs attrs def getlengthself return lenself attrs def gettypeself name return cdata def getvalueself name return self attrsname def getvaluebyqnameself name return self attrsname def getnamebyqnameself name if name not in self attrs raise keyerrorname return name def getqnamebynameself name if name not in self attrs raise keyerrorname return name def getnamesself return listself attrs keys def getqnamesself return listself attrs keys def lenself return lenself attrs def getitemself name return self attrsname def keysself return listself attrs keys def containsself name return name in self attrs def getself name alternativenone return self attrs getname alternative def copyself return self classself attrs def itemsself return listself attrs items def valuesself return listself attrs values attributesnsimpl class attributesnsimplattributesimpl def initself attrs qnames xmlreader interface for reading an xml document using callbacks xmlreader is the interface that an xml parser s sax2 driver must implement this interface allows an application to set and query features and properties in the parser to register event handlers for document processing and to initiate a document parse all sax interfaces are assumed to be synchronous the parse methods must not return until parsing is complete and readers must wait for an event handler callback to return before reporting the next event 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 raise a sax exception applications may request a locale change in the middle of a parse 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 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 this method is called by the parse implementation to allow the sax 2 0 driver to prepare itself for parsing 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 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 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 inputsource encapsulation of the information needed by the xmlreader to read entities this class may include information about the public identifier system identifier byte stream possibly with character encoding information and or the character stream of an entity applications will create objects of this class for use in the xmlreader parse method and for returning from entityresolver resolveentity an inputsource belongs to the application the xmlreader is not allowed to modify inputsource objects passed to it from the application although it may make copies and modify those sets the character encoding of this inputsource the encoding must be a string acceptable for an xml encoding declaration see section 4 3 3 of the xml recommendation the encoding attribute of the inputsource is ignored if the inputsource also contains a character stream set the byte stream a python file like object which does not perform byte to character conversion for this input source the sax parser will ignore this if there is also a character stream specified but it will use a byte stream in preference to opening a uri connection itself if the application knows the character encoding of the byte stream it should set it with the setencoding method get the byte stream for this input source the getencoding method will return the character encoding for this byte stream or none if unknown set the character stream for this input source the stream must be a python 2 0 unicode wrapped file like that performs conversion to unicode strings if there is a character stream specified the sax parser will ignore any byte stream and will not attempt to open a uri connection to the system identifier attributesimpl non ns aware implementation attrs should be of the form name value attributesnsimpl ns aware implementation attrs should be of the form ns_uri lname value qnames of the form ns_uri lname qname
from . import handler

from ._exceptions import SAXNotSupportedException, SAXNotRecognizedException




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):
        
        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):
    

    def __init__(self, bufsize=2**16):
        self._bufsize = bufsize
        XMLReader.__init__(self)

    def parse(self, source):
        from . import saxutils
        source = saxutils.prepare_input_source(source)

        self.prepareParser(source)
        file = source.getCharacterStream()
        if file is None:
            file = source.getByteStream()
        while buffer := file.read(self._bufsize):
            self.feed(buffer)
        self.close()

    def feed(self, data):
        
        raise NotImplementedError("This method must be implemented!")

    def prepareParser(self, source):
        
        raise NotImplementedError("prepareParser must be overridden!")

    def close(self):
        
        raise NotImplementedError("This method must be implemented!")

    def reset(self):
        
        raise NotImplementedError("This method must be implemented!")



class Locator:
    

    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



class InputSource:
    

    def __init__(self, system_id = None):
        self.__system_id = system_id
        self.__public_id = None
        self.__encoding  = None
        self.__bytefile  = None
        self.__charfile  = None

    def setPublicId(self, public_id):
        "Sets the public identifier of this InputSource."
        self.__public_id = public_id

    def getPublicId(self):
        "Returns the public identifier of this InputSource."
        return self.__public_id

    def setSystemId(self, system_id):
        "Sets the system identifier of this InputSource."
        self.__system_id = system_id

    def getSystemId(self):
        "Returns the system identifier of this InputSource."
        return self.__system_id

    def setEncoding(self, encoding):
        
        self.__encoding = encoding

    def getEncoding(self):
        "Get the character encoding of this InputSource."
        return self.__encoding

    def setByteStream(self, bytefile):
        
        self.__bytefile = bytefile

    def getByteStream(self):
        
        return self.__bytefile

    def setCharacterStream(self, charfile):
        
        self.__charfile = charfile

    def getCharacterStream(self):
        "Get the character stream for this input source."
        return self.__charfile



class AttributesImpl:

    def __init__(self, attrs):
        
        self._attrs = attrs

    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[name]

    def getNameByQName(self, name):
        if name not in self._attrs:
            raise KeyError(name)
        return name

    def getQNameByName(self, name):
        if name not in self._attrs:
            raise KeyError(name)
        return name

    def getNames(self):
        return list(self._attrs.keys())

    def getQNames(self):
        return list(self._attrs.keys())

    def __len__(self):
        return len(self._attrs)

    def __getitem__(self, name):
        return self._attrs[name]

    def keys(self):
        return list(self._attrs.keys())

    def __contains__(self, name):
        return name in self._attrs

    def get(self, name, alternative=None):
        return self._attrs.get(name, alternative)

    def copy(self):
        return self.__class__(self._attrs)

    def items(self):
        return list(self._attrs.items())

    def values(self):
        return list(self._attrs.values())



class AttributesNSImpl(AttributesImpl):

    def __init__(self, attrs, qnames):
        
        self._attrs = attrs
        self._qnames = qnames

    def getValueByQName(self, name):
        for (nsname, qname) in self._qnames.items():
            if qname == name:
                return self._attrs[nsname]

        raise KeyError(name)

    def getNameByQName(self, name):
        for (nsname, qname) in self._qnames.items():
            if qname == name:
                return nsname

        raise KeyError(name)

    def getQNameByName(self, name):
        return self._qnames[name]

    def getQNames(self):
        return list(self._qnames.values())

    def copy(self):
        return self.__class__(self._attrs, self._qnames)


def _test():
    XMLReader()
    IncrementalParser()
    Locator()

if __name__ == "__main__":
    _test()