delete xmark.bracket

from lxml import etree

import lxml.sax

from xml.sax.handler import ContentHandler

# This class implements the sax-like events for converting XML elemnts into

# bracket-notation nodes and labels.

class XMarkContentHandler(ContentHandler):

    def __init__(self):

        self.bn = ""

    # Open tag.

    def startElementNS(self, name, qname, attributes):

        uri, localname = name

        self.bn += "{" + localname

        d = dict(attributes)

        # Sort the attributes by their keys.

        for key, value in sorted(d.items(), key = lambda element : element[0][1]):

            self.bn += "{" + key[1].translate(str.maketrans({"{":  r"\{",

                                          "}":  r"\}",

                                          "\\": r"\\"})) + "{" + value.translate(str.maketrans({"{":  r"\{",

                                          "}":  r"\}",

                                          "\\": r"\\"})) + "}}"

    # Close tag.

    def endElementNS(self, name, qname):

        self.bn += "}"

    # Tag content.

    def characters(self, data):

        self.bn += "{" + data.translate(str.maketrans({"{":  r"\{",

                                          "}":  r"\}",

                                          "\\": r"\\"})) + "}"

print("--- Loading XMARK dataset.")

xmark_parser = etree.XMLParser(load_dtd=True, remove_blank_text=True)

xmark_data_tree = etree.parse('standard', xmark_parser)

root = xmark_data_tree.getroot()

# Output files.

xmark_bracket = open('xmark.bracket', 'w')

print("--- Processing each child of xmark's root.")

tree_id = 0

for child in root:

    tree_id += 1

    # Printing simple progress.

    if tree_id % 10000 == 0:

        print("- Tree %s" % (tree_id))

    handler = XMarkContentHandler()

    lxml.sax.saxify(child, handler)

    xmark_bracket.write(handler.bn + "\n")

print("--- Closing output files.")

xmark_bracket.close()