giscanner/xmlwriter.py

   1 # -*- Mode: Python -*-
   2 # GObject-Introspection - a framework for introspecting GObject libraries
   3 # Copyright (C) 2008  Johan Dahlin
   4 #
   5 # This library is free software; you can redistribute it and/or
   6 # modify it under the terms of the GNU Lesser General Public
   7 # License as published by the Free Software Foundation; either
   8 # version 2 of the License, or (at your option) any later version.
   9 #
  10 # This library is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 # Lesser General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU Lesser General Public
  16 # License along with this library; if not, write to the
  17 # Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18 # Boston, MA 02111-1307, USA.
  19 #
  20
  21 from __future__ import with_statement
  22
  23 import os
  24
  25 from contextlib import contextmanager
  26 from cStringIO import StringIO
  27 from xml.sax.saxutils import escape
  28
  29 from .libtoolimporter import LibtoolImporter
  30
  31
  32 with LibtoolImporter(None, None):
  33     if 'UNINSTALLED_INTROSPECTION_SRCDIR' in os.environ:
  34         from _giscanner import collect_attributes
  35     else:
  36         from giscanner._giscanner import collect_attributes
  37
  38
  39 def build_xml_tag(tag_name, attributes=None, data=None, self_indent=0,
  40                   self_indent_char=' '):
  41     if attributes is None:
  42         attributes = []
  43     prefix = u'<%s' % (tag_name, )
  44     if data is not None:
  45         if isinstance(data, str):
  46             data = data.decode('UTF-8')
  47         suffix = u'>%s</%s>' % (escape(data), tag_name)
  48     else:
  49         suffix = u'/>'
  50     attrs = collect_attributes(
  51         tag_name, attributes,
  52         self_indent,
  53         self_indent_char,
  54         len(prefix) + len(suffix))
  55     return prefix + attrs + suffix
  56
  57
  58 class XMLWriter(object):
  59
  60     def __init__(self):
  61         self._data = StringIO()
  62         self._data.write('<?xml version="1.0"?>\n')
  63         self._tag_stack = []
  64         self._indent = 0
  65         self._indent_unit = 2
  66         self.enable_whitespace()
  67
  68     # Private
  69
  70     def _open_tag(self, tag_name, attributes=None):
  71         if attributes is None:
  72             attributes = []
  73         attrs = collect_attributes(tag_name, attributes,
  74                                    self._indent, self._indent_char, len(tag_name) + 2)
  75         self.write_line(u'<%s%s>' % (tag_name, attrs))
  76
  77     def _close_tag(self, tag_name):
  78         self.write_line(u'</%s>' % (tag_name, ))
  79
  80     # Public API
  81
  82     def enable_whitespace(self):
  83         self._indent_char = ' '
  84         self._newline_char = '\n'
  85
  86     def disable_whitespace(self):
  87         self._indent_char = ''
  88         self._newline_char = ''
  89
  90     def get_xml(self):
  91         return self._data.getvalue()
  92
  93     def write_line(self, line=u'', indent=True, do_escape=False):
  94         if isinstance(line, str):
  95             line = line.decode('utf-8')
  96         assert isinstance(line, unicode)
  97         if do_escape:
  98             line = escape(line)
  99         if indent:
 100             self._data.write('%s%s%s' % (self._indent_char * self._indent,
 101                                          line.encode('utf-8'),
 102                                          self._newline_char))
 103         else:
 104             self._data.write('%s%s' % (line.encode('utf-8'), self._newline_char))
 105
 106     def write_comment(self, text):
 107         self.write_line('<!-- %s -->' % (text, ))
 108
 109     def write_tag(self, tag_name, attributes, data=None):
 110         self.write_line(build_xml_tag(tag_name, attributes, data,
 111                                       self._indent, self._indent_char))
 112
 113     def push_tag(self, tag_name, attributes=None):
 114         if attributes is None:
 115             attributes = []
 116         self._open_tag(tag_name, attributes)
 117         self._tag_stack.append(tag_name)
 118         self._indent += self._indent_unit
 119
 120     def pop_tag(self):
 121         self._indent -= self._indent_unit
 122         tag_name = self._tag_stack.pop()
 123         self._close_tag(tag_name)
 124         return tag_name
 125
 126     @contextmanager
 127     def tagcontext(self, tag_name, attributes=None):
 128         self.push_tag(tag_name, attributes)
 129         try:
 130             yield
 131         finally:
 132             self.pop_tag()
 133
 134
 135 def test():
 136     w = XMLWriter()
 137     w.push_tag('repository')
 138     w.push_tag('namespace')
 139     w.push_tag('enumeration')
 140     w.push_tag('member',
 141                [('name', 'west'),
 142                 ('value', '7'),
 143                 ('c:identifier', 'GTK_ANCHOR_WEST'),
 144                 ('glib:nick', 'west')])
 145
 146     w.pop_tag()
 147     w.pop_tag()
 148     w.pop_tag()
 149     x = w.get_xml()
 150     lines = x.split('\n')
 151     import pprint
 152     pprint.pprint(lines)
 153     assert len(lines[3]) < 80, len(lines[3])
 154
 155 if __name__ == '__main__':
 156     test()