Source code for ocrd_models.ocrd_xml_base

"""
Base class for XML documents loaded from either content or filename.
"""
from os.path import exists
from lxml import etree as ET

from .constants import NAMESPACES
from .utils import xmllint_format


for curie in NAMESPACES:
    ET.register_namespace(curie, NAMESPACES[curie])



class OcrdXmlDocument():
    """
    Base class for XML documents loaded from either content or filename.
    """

    def __init__(self, filename=None, content=None, cache_flag=False):
        """
        Args:
            filename (string):
            content (string):
            cache_flag (bool):
        """
        #  print(self, filename, content)
        if filename is None and content is None:
            raise Exception("Must pass 'filename' or 'content' to " + self.__class__.__name__)
        elif content:
            self._tree = ET.ElementTree(ET.XML(content, parser=ET.XMLParser(encoding='utf-8')))
        else:
            assert filename
            filename = filename.replace('file://', '')
            if not exists(filename):
                raise Exception('File does not exist: %s' % filename)
            self._tree = ET.parse(filename)

        # Cache enabled - True/False
        self._cache_flag = cache_flag



    def to_xml(self, xmllint=False):
        """
        Serialize all properties as pretty-printed XML

        Args:
            xmllint (boolean): Format with ``xmllint`` in addition to pretty-printing
        """
        root = self._tree.getroot()
        ret = ET.tostring(ET.ElementTree(root), pretty_print=True, encoding='UTF-8')
        if xmllint:
            ret = xmllint_format(ret)
        return ret