13.8 xml.sax.xmlreader -- Interface for XML parsers
Keywords: lib

# 13.8 `xml.sax.xmlreader` -- Interface for XML parsers

New in version 2.0.

SAX parsers implement the `XMLReader` interface. They are implemented in a Python module, which must provide a function `create_parser()`. This function is invoked by `xml.sax.make_parser()` with no arguments to create a new parser object.

`XMLReader` ()
  Base class which can be inherited by SAX parsers.

`IncrementalParser` ()
  In some cases, it is desirable not to parse an input source at once, but to feed chunks of the document as they get available. Note that the reader will normally not read the entire file, but read it in chunks as well; still `parse()` won't return until the entire document is processed. So these interfaces should be used if the blocking behaviour of `parse()` is not desirable.

  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.

`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. If information is not available, methods may return `None`.

`InputSource` ([systemId])
  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.

`AttributesImpl` (attrs)
  This is a dictionary-like object which represents the element attributes in a `startElement()` call. In addition to the most useful dictionary operations, it supports a number of other methods as described below. Objects of this class should be instantiated by readers; attrs must be a dictionary-like object.

`AttributesNSImpl` (attrs, qnames)
  Namespace-aware variant of attributes, which will be passed to `startElementNS()`. It is derived from `AttributesImpl`, but understands attribute names as two-tuples of namespaceURI and localname. In addition, it provides a number of methods expecting qualified names as they appear in the original document.

Subsections

- 13.8.1 XMLReader Objects
- 13.8.2 IncrementalParser Objects
- 13.8.3 Locator Objects
- 13.8.4 InputSource Objects
- 13.8.5 AttributesImpl Objects
- 13.8.6 AttributesNSImpl Objects