1"""Simple API for XML (SAX) implementation for Python.
2
3This module provides an implementation of the SAX 2 interface;
4information about the Java version of the interface can be found at
5http://www.megginson.com/SAX/.  The Python version of the interface is
6documented at <...>.
7
8This package contains the following modules:
9
10handler -- Base classes and constants which define the SAX 2 API for
11           the 'client-side' of SAX for Python.
12
13saxutils -- Implementation of the convenience classes commonly used to
14            work with SAX.
15
16xmlreader -- Base classes and constants which define the SAX 2 API for
17             the parsers used with SAX for Python.
18
19expatreader -- Driver that allows use of the Expat parser with SAX.
20"""
21
22from xmlreader import InputSource
23from handler import ContentHandler, ErrorHandler
24from _exceptions import SAXException, SAXNotRecognizedException, \
25                        SAXParseException, SAXNotSupportedException, \
26                        SAXReaderNotAvailable
27
28
29def parse(source, handler, errorHandler=ErrorHandler()):
30    parser = make_parser()
31    parser.setContentHandler(handler)
32    parser.setErrorHandler(errorHandler)
33    parser.parse(source)
34
35def parseString(string, handler, errorHandler=ErrorHandler()):
36    try:
37        from cStringIO import StringIO
38    except ImportError:
39        from StringIO import StringIO
40
41    if errorHandler is None:
42        errorHandler = ErrorHandler()
43    parser = make_parser()
44    parser.setContentHandler(handler)
45    parser.setErrorHandler(errorHandler)
46
47    inpsrc = InputSource()
48    inpsrc.setByteStream(StringIO(string))
49    parser.parse(inpsrc)
50
51# this is the parser list used by the make_parser function if no
52# alternatives are given as parameters to the function
53
54default_parser_list = ["xml.sax.expatreader"]
55
56# tell modulefinder that importing sax potentially imports expatreader
57_false = 0
58if _false:
59    import xml.sax.expatreader
60
61import os, sys
62if "PY_SAX_PARSER" in os.environ:
63    default_parser_list = os.environ["PY_SAX_PARSER"].split(",")
64del os
65
66_key = "python.xml.sax.parser"
67if sys.platform[:4] == "java" and sys.registry.containsKey(_key):
68    default_parser_list = sys.registry.getProperty(_key).split(",")
69
70
71def make_parser(parser_list = []):
72    """Creates and returns a SAX parser.
73
74    Creates the first parser it is able to instantiate of the ones
75    given in the list created by doing parser_list +
76    default_parser_list.  The lists must contain the names of Python
77    modules containing both a SAX parser and a create_parser function."""
78
79    for parser_name in parser_list + default_parser_list:
80        try:
81            return _create_parser(parser_name)
82        except ImportError,e:
83            import sys
84            if parser_name in sys.modules:
85                # The parser module was found, but importing it
86                # failed unexpectedly, pass this exception through
87                raise
88        except SAXReaderNotAvailable:
89            # The parser module detected that it won't work properly,
90            # so try the next one
91            pass
92
93    raise SAXReaderNotAvailable("No parsers found", None)
94
95# --- Internal utility methods used by make_parser
96
97if sys.platform[ : 4] == "java":
98    def _create_parser(parser_name):
99        from org.python.core import imp
100        drv_module = imp.importName(parser_name, 0, globals())
101        return drv_module.create_parser()
102
103else:
104    def _create_parser(parser_name):
105        drv_module = __import__(parser_name,{},{},['create_parser'])
106        return drv_module.create_parser()
107
108del sys
109