2 """XML Virtual FileSystem for Midnight Commander
4 The script requires Midnight Commander 3.1+
5 (http://www.midnight-commander.org/), Python 2.4+ (http://www.python.org/).
7 For mc 4.7+ put the script in $HOME/[.local/share/].mc/extfs.d.
8 For older versions put it in /usr/[local/][lib|share]/mc/extfs
9 and add a line "xml" to the /usr/[local/][lib|share]/mc/extfs/extfs.ini.
10 Make the script executable.
12 For mc 4.7+ run this "cd" command in the Midnight Commander (in the "bindings"
13 file the command is "%cd"): cd file/xml://; In older versions it is
14 cd file#xml, where "file" is the name of your XML file.
16 The VFS represents tags as directories; the directories are numbered to
17 distinguish tags with the same name; also numbering helps to sort tags by their
18 order in XML instead of sorting them by name. Attributes, text nodes and
19 comments are represented as text files; attributes are shown in a file named
20 "attributes", attributes are listed in the file as name=value lines (I
21 deliberately ignore a small chance of newline characters in values); names and
22 values are reencoded to the console encoding. Text nodes and comments are
23 collected in a file named "text", stripped and reencoded. The filesystem is
26 It is useful to have a top-down view on an XML structure but it's especially
27 convenient to extract text values from tags. One can get, for example, a
28 base64-encoded image - just walk down the VFS to the tag's directory and copy
29 its text file to a real file.
31 The VFS was inspired by a FUSE xmlfs: https://github.com/halhen/xmlfs
36 __author__ = "Oleg Broytman <phd@phdru.name>"
37 __copyright__ = "Copyright (C) 2013 PhiloSoft Design"
42 import xml.dom.minidom
51 # Get the default charset.
53 lcAll = locale.getdefaultlocale()
54 except locale.Error, err:
55 print >>sys.stderr, "WARNING:", err
59 default_encoding = lcAll[1]
62 default_encoding = locale.getpreferredencoding()
63 except locale.Error, err:
64 print >>sys.stderr, "WARNING:", err
65 default_encoding = sys.getdefaultencoding()
67 default_encoding = sys.getdefaultencoding()
70 logger = logging.getLogger('xml-mcextfs')
71 log_err_handler = logging.StreamHandler(sys.stderr)
72 logger.addHandler(log_err_handler)
73 logger.setLevel(logging.INFO)
77 XML Virtual FileSystem for Midnight Commander version %s
81 This is not a program. Put the script in $HOME/[.local/share/].mc/extfs.d or
82 /usr/[local/][lib|share]/mc/extfs. For more information read the source!""",
83 __version__, __author__, __copyright__
88 locale.setlocale(locale.LC_ALL, '')
94 class MiniDOM(XmlVfs):
96 self.document = xml.dom.minidom.parse(sys.argv[2])
98 def hasattrs(self, node):
99 return bool(node.attributes)
101 def attrs2text(self, node):
102 attrs = node.attributes
103 attrs = [attrs.item(i) for i in range (attrs.length)]
104 return '\n'.join(["%s=%s" %
105 (a.name.encode(default_encoding, "replace"),
106 a.value.encode(default_encoding, "replace"))
109 def collect_text(self, node):
110 text_accumulator = []
111 for element in node.childNodes:
112 if element.localName:
114 elif element.nodeType == element.COMMENT_NODE:
115 text = u"<!--%s-->" % element.nodeValue
116 elif element.nodeType == element.TEXT_NODE:
117 text = element.nodeValue.strip()
119 xml_error("Unknown node type %d" % element.nodeType)
120 if text: text_accumulator.append(text)
121 return '\n'.join(text_accumulator).encode(default_encoding, "replace")
124 self._list(self.document)
126 def _list(self, node, path=''):
127 childNodes = node.childNodes
129 for element in childNodes:
130 if element.localName:
133 width = int(math.log10(n))+1
134 template = "%%0%dd" % width
138 for element in childNodes:
139 if element.localName:
142 subpath = '%s/%s %s' % (path, template % n, element.localName)
144 subpath = '%s %s' % (template % n, element.localName)
145 subpath_encoded = subpath.encode(default_encoding, "replace")
146 print "dr-xr-xr-x 1 user group 0 Jan 1 00:00 %s" % subpath_encoded
147 if self.hasattrs(element):
148 attr_text = self.attrs2text(element)
149 print "-r--r--r-- 1 user group %d Jan 1 00:00 %s/attributes" % (
150 len(attr_text), subpath_encoded)
151 text = self.collect_text(element)
153 print "-r--r--r-- 1 user group %d Jan 1 00:00 %s/text" % (
154 len(text), subpath_encoded)
155 self._list(element, subpath)
160 def get_child_node(self, node, i):
162 for element in node.childNodes:
163 if element.localName:
167 xml_error('There are less than %d nodes' % i)
171 """List the entire VFS"""
178 """Extract a file from the VFS"""
181 xml_filename = sys.argv[3]
182 real_filename = sys.argv[4]
184 node = xmlvfs.getroot()
185 for path_comp in xml_filename.split('/'):
187 i = int(path_comp.split(' ', 1)[0])
188 node = xmlvfs.get_child_node(node, i)
189 elif path_comp in ('attributes', 'text'):
192 xml_error('Unknown file')
194 if path_comp == 'attributes':
195 if xmlvfs.hasattrs(node):
196 text = xmlvfs.attrs2text(node)
198 xml_error('There are no attributes')
200 if path_comp == 'text':
201 text = xmlvfs.collect_text(node)
203 outfile = open(real_filename, 'w')
209 """Put a file to the VFS"""
210 sys.exit("XML VFS doesn't support adding files (read-only filesystem)")
213 """Remove a file from the VFS"""
214 sys.exit("XML VFS doesn't support removing files/directories (read-only filesystem)")
216 mcxml_rmdir = mcxml_rm
219 """Create a directory in the VFS"""
220 sys.exit("XML VFS doesn't support creating directories (read-only filesystem)")
223 def xml_error(error_str):
224 logger.critical("Error walking XML file: %s", error_str)
227 command = sys.argv[1]
228 procname = "mcxml_" + command
231 if not g.has_key(procname):
232 logger.critical("Unknown command %s", command)
240 logger.exception("Error during run")