def __init__(self, href, opf_str = None, container_path = None, package = None):
'''
Parameters
----------
href : string
Absolute file path of this opf through which it is being opened.
Keyword arguments:
opf_str -- if available the contents of the OPF file itself to parse (Default None)
container_path -- the path of this opf within the epub container (Default None)
'''
# The etree root element
if opf_str:
self.package_el = etree.fromstring(opf_str)
#check for a title - old versions of eXe made invalid opfs with no title
if self._get_title_el() is None:
metadata_el = self.package_el.find(".//{%s}metadata" % EPUBOPF.NAMESPACE_OPF)
title_el = etree.SubElement(metadata_el, "{%s}title" % EPUBOPF.NAMESPACE_DC)
title_el.text = "Package"
else:
self.package_el = None # this could be construction of a blank item
self.href = href
self.nav_el_id = None
self.navigation_doc = None
self.container_path = container_path
self.package = package
self.resource_manager = EPUBResourceManager(self.package, self)
