def add_iso_md_element(xml_obj: _Element, new_link: str):
""" Adds a new MetadataURL element to the parent xml_obj
Args:
xml_obj (_Element): The parent xml object which holds all MetadataURL elements
new_link (str): The link of the new metadata resource
Returns:
nothing
"""
iso_elem = etree.Element("MetadataURL", {"type": "ISO19115:2003"},
nsmap={"xlink": "http://www.w3.org/1999/xlink"})
iso_elem_format = etree.SubElement(iso_elem, "Format")
iso_elem_format.text = "text/xml"
iso_elem_resource = etree.SubElement(
iso_elem, "OnlineResource", {
"{http://www.w3.org/1999/xlink}type": "simple",
"{http://www.w3.org/1999/xlink}href": new_link
})
# try to append where other metadaURL elements might already exist
# if there are no other elements -> just append it at the end
other_iso_md_elements = try_get_element_from_xml("./MetadataURL", xml_obj)
if len(other_iso_md_elements):
index = 0
for other_iso in other_iso_md_elements:
i = xml_obj.index(other_iso)
if i > index:
index = i
index += 1
xml_obj.insert(index, iso_elem)
else:
xml_obj.append(iso_elem)
def sign(
*,
element: Element,
private_key: RSAPrivateKey,
certificate: Certificate,
config: SigningConfig = SigningConfig.default(),
index: int = 0,
) -> bytes:
try:
element_id = element.attrib["ID"]
except KeyError:
raise NoIDAttribute(element)
# Generate the digest value of the element/content to be signed
content_digest_value = utils.ascii_b64(
utils.hash_digest(config.digest_method, utils.serialize_xml(element)))
# Build the SignedInfo tag, referencing the element we got passed,
# including the digest value we just created.
signed_info = ds.SignedInfo(
ds.CanonicalizationMethod(Algorithm=XML_EXC_C14N),
ds.SignatureMethod(Algorithm=utils.signature_method_algorithm(
config.signature_method)),
ds.Reference(
ds.Transforms(
ds.Transform(Algorithm=XMLDSIG_ENVELOPED_SIGNATURE),
ds.Transform(Algorithm=XML_EXC_C14N),
),
ds.DigestMethod(
Algorithm=utils.digest_method_algorithm(config.digest_method)),
ds.DigestValue(content_digest_value), # Embed the digest value
URI="#" + element_id, # Reference the element to sign
),
)
# Sign the digest of the SignedInfo element
signature = utils.sign(utils.serialize_xml(signed_info), private_key,
config.signature_method)
signature_value = utils.ascii_b64(signature)
# Encode the certificate to embed into the signature.
cert_data = utils.ascii_b64(certificate.public_bytes(Encoding.DER))
signature_element = ds.Signature(
signed_info,
ds.SignatureValue(signature_value),
ds.KeyInfo(ds.X509Data(ds.X509Certificate(cert_data))),
)
element.insert(index, signature_element)
root = utils.get_root(element)
result = utils.serialize_xml(root)
element.remove(signature_element)
return result
def create_subelement(xml_elem: _Element, tag_name, after: str = None, attrib: dict = None, nsmap: dict = {}):
""" Creates a new xml element as a child of xml_elem with the name tag_name
Args:
xml_elem: The xml element
tag_name: The tag name for the new element
after (str): The tag name of the element after which the new one should be inserted
attrib: The attribute dict for the new element
Returns:
A new subelement of xml_elem
"""
ret_element = etree.Element(tag_name, attrib=attrib, nsmap=nsmap)
if after is not None:
after_element = try_get_single_element_from_xml("./{}".format(after), xml_elem)
after_element_index = xml_elem.index(after_element) + 1
xml_elem.insert(after_element_index, ret_element)
else:
xml_elem.append(ret_element)
return ret_element
def add_subelement(parent_elem: _Element, sub_element: _Element, after: str = None):
""" Adds an existing xml element after
Args:
parent_elem: The parent xml element
sub_element: The sub xml element
Returns:
parent_elem: The modified xml element, holding the subelement as a child
"""
if after is not None:
after_element = try_get_single_element_from_xml("./{}".format(after), parent_elem)
if after_element is None:
# If this element could not be found, we append this element at the end
after_element_index = -1
else:
after_element_index = parent_elem.index(after_element) + 1
parent_elem.insert(after_element_index, sub_element)
else:
parent_elem.append(sub_element)
return parent_elem
def arrange_feed_top_level_element(self, dom: etree._Element, rss_url_prefix: str, parameters: Dict[str, str], favicon_url:str):
icons = xpath(dom, "./icon")
icon_node: etree._Element
if len(icons) == 0:
icon_node = etree.Element("icon")
dom.insert(0, icon_node)
else:
icon_node = icons[0]
icon_node.text = favicon_url
icon = etree.Element("{%s}icon" %
NAMESPACES["atom"], nsmap=NAMESPACES)
icon.text = favicon_url
dom.insert(0, icon)
# arrange links in channel
other_link_nodes = xpath(
dom, "./*[local-name()='link' and @type='application/atom+xml']")
for link_node in other_link_nodes:
if "href" in link_node.attrib:
link_node.attrib["href"] = self._generated_complete_url(
rss_url_prefix, parameters)
else:
link_node.text = self._generated_complete_url(
rss_url_prefix, parameters)
