COT.xml_file module

Reading, editing, and writing XML files.

class XML(xml_file)

Bases: object

Class capable of reading, editing, and writing XML files.

__init__(xml_file)

Read the given XML file and store it in memory.

The memory representation is available as properties tree and root.

Parameters:xml_file (str) -- File path to read. Raises:xml.etree.ElementTree.ParseError -- if parsing fails

classmethod add_child(parent, new_child, ordering=None, known_namespaces=None)

Add the given child element under the given parent element.

Parameters:

• parent (xml.etree.ElementTree.Element) -- Parent element
• new_child (xml.etree.ElementTree.Element) -- Child element to attach
• ordering (list) -- (Optional) List describing the expected ordering of child tags under the parent; if a new child element is created, its placement under the parent will respect this sequence.
• known_namespaces (list) -- (Optional) List of well-understood XML namespaces. If a new child is created, and ordering is given, any tag (new or existing) that is encountered but not accounted for in ordering will result in COT logging a warning if and only if the unaccounted-for tag is in a known namespace.

classmethod find_all_children(parent, tag, attrib=None)

Find all matching child elements under the specified parent element.

Parameters:

• parent (xml.etree.ElementTree.Element) -- Parent element
• tag (iterable) -- Child tag string (or list of tags) to match on
• attrib (dict) -- Child attributes to match on

Returns:

list -- (Possibly empty) list of matching child Elements

classmethod find_child(parent, tag, attrib=None, required=False)

Find the unique child element under the specified parent element.

Parameters:

• parent (xml.etree.ElementTree.Element) -- Parent element
• tag (str) -- Child tag to match on
• attrib (dict) -- Child attributes to match on
• required (boolean) -- Whether to raise an error if no child exists

Raises:

• LookupError -- if more than one matching child is found
• KeyError -- if no matching child is found and required is True

Returns:

xml.etree.ElementTree.Element -- Child element found, or None

static get_ns(text)

Get the namespace prefix from an XML element or attribute name.

Parameters:text (str) -- Element name or attribute name, such as "{http://schemas.dmtf.org/ovf/envelope/1}Element". Returns:str -- "" if no prefix is present, or a namespace prefix, such as "http://schemas.dmtf.org/ovf/envelope/1".

classmethod set_or_make_child(parent, tag, text=None, attrib=None, ordering=None, known_namespaces=None)

Update or create a child element under the specified parent element.

Parameters:

• parent (xml.etree.ElementTree.Element) -- Parent element
• tag (str) -- Child element text tag to find or create
• text (str) -- Value to set the child's text attribute to
• attrib (dict) -- Dict of child attributes to match on while searching and set in the final child element
• ordering (list) -- See add_child()
• known_namespaces (list) -- See add_child()

Returns:

xml.etree.ElementTree.Element -- New or updated child Element.

static strip_ns(text)

Remove a namespace prefix from an XML element or attribute name.

Parameters:text (str) -- Element name or attribute name, such as "{http://schemas.dmtf.org/ovf/envelope/1}Element". Returns:str -- Bare name, such as "Element".

write_xml(xml_file)

Write pretty XML out to the given file.

Parameters:xml_file (str) -- Filename to write to

static xml_reindent(parent, depth=0)

Recursively add indentation to XML to make it look nice.

Parameters:

• parent (xml.etree.ElementTree.Element) -- Current parent element
• depth (int) -- How far down the rabbit hole we have recursed. Increments by 2 for each successive level of nesting.

root = None

Root xml.etree.ElementTree.Element instance of the tree.

tree = None

xml.etree.ElementTree.ElementTree describing this file.