| | """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 |
| |
|
| |
|
| | |
| |
|
| | class 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.""" |
| |
|
| | 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 raise 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): |
| | from . import saxutils |
| | source = saxutils.prepare_input_source(source) |
| |
|
| | self.prepareParser(source) |
| | file = source.getCharacterStream() |
| | if file is None: |
| | file = source.getByteStream() |
| | buffer = file.read(self._bufsize) |
| | while buffer: |
| | self.feed(buffer) |
| | buffer = file.read(self._bufsize) |
| | self.close() |
| |
|
| | 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!") |
| |
|
| | |
| |
|
| | 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 |
| |
|
| | |
| |
|
| | class 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.""" |
| |
|
| | 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): |
| | """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 getEncoding(self): |
| | "Get the character encoding of this InputSource." |
| | return self.__encoding |
| |
|
| | def setByteStream(self, bytefile): |
| | """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.""" |
| | self.__bytefile = bytefile |
| |
|
| | def getByteStream(self): |
| | """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 setCharacterStream(self, charfile): |
| | """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.""" |
| | self.__charfile = charfile |
| |
|
| | def getCharacterStream(self): |
| | "Get the character stream for this input source." |
| | return self.__charfile |
| |
|
| | |
| |
|
| | class AttributesImpl: |
| |
|
| | def __init__(self, attrs): |
| | """Non-NS-aware implementation. |
| | |
| | attrs should be of the form {name : value}.""" |
| | 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): |
| | """NS-aware implementation. |
| | |
| | attrs should be of the form {(ns_uri, lname): value, ...}. |
| | qnames of the form {(ns_uri, lname): qname, ...}.""" |
| | 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() |
| |
|