PyXB XML Object to String

Question

Given a PyXB object, how can one turn it into a string?

I used PyXB to generate an XML document, which I would like to then turn into a dictionary using the xmltodict module. The issue is that xmltodict.parse takes a bytes-like object, which the PyXB object of course, is not.

Answer 1

I found a method in the python d1_python library that accomplishes this. The method takes a PyXB object and will serialize it with the given encoding.

  def serialize_gen(obj_pyxb, encoding, pretty=False, strip_prolog=False):
  """Serialize a PyXB object to XML
  - If {pretty} is True, format for human readability.
  - If {strip_prolog} is True, remove any XML prolog (e.g., <?xml version="1.0"
  encoding="utf-8"?>), from the resulting string.
  """
  assert is_pyxb(obj_pyxb)
  assert encoding in (None, 'utf-8')
  try:
    if pretty:
      pretty_xml = obj_pyxb.toDOM().toprettyxml(indent='  ', encoding=encoding)
      # Remove empty lines in the result caused by a bug in toprettyxml()
      if encoding is None:
        pretty_xml = re.sub(r'^\s*$\n', r'', pretty_xml, flags=re.MULTILINE)
      else:
        pretty_xml = re.sub(b'^\s*$\n', b'', pretty_xml, flags=re.MULTILINE)
    else:
      pretty_xml = obj_pyxb.toxml(encoding)
    if strip_prolog:
      if encoding is None:
        pretty_xml = re.sub(r'^<\?(.*)\?>', r'', pretty_xml)
      else:
        pretty_xml = re.sub(b'^<\?(.*)\?>', b'', pretty_xml)
    return pretty_xml.strip()
  except pyxb.ValidationError as e:
    raise ValueError(
      'Unable to serialize PyXB to XML. error="{}"'.format(e.details())
    )
  except pyxb.PyXBException as e:
    raise ValueError(
      'Unable to serialize PyXB to XML. error="{}"'.format(str(e))
    )

As an example, you can parse a PyXB object to UTF-8 with

serialize_gen(pyxb_object, utf-8)

To convert the object to a string, it would be called as

serialize_gen(pyxb_object, None)