NuKVM/virt-manager
3
0
Fork 0
mirror of https://github.com/virt-manager/virt-manager.git synced 2025-02-25 18:55:27 -06:00
Code Issues Packages Projects Releases Wiki Activity

xmlbuilder: More comments for _build_xpath_node

Browse Source
This commit is contained in:
Cole Robinson 2016-07-18 13:50:25 -04:00
parent a931a1a6ad
commit 835ddc5f77
1 changed files with 30 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
virtinst/xmlbuilder.py
View File

@ -158,44 +158,56 @@ def _add_pretty_child(parentnode, newnode):
def _build_xpath_node(ctx, xpath): def _build_xpath_node(ctx, xpath):
""" """
Build all nodes required to set an xpath. If we have XML <foo/>, and want Build all nodes for the passed xpath. For example, if 'ctx' xml=<foo/>,
to set xpath /foo/bar/baz@booyeah, we create node 'bar' and 'baz' and xpath=./bar/@baz, after this function the 'ctx' XML will be:
returning the last node created.
<foo>
<bar baz=''/>
</foo>
And the node pointing to @baz will be returned, for the caller to
do with as they please.
""" """
parentpath = "" def _handle_node(nodename, parentnode, parentpath):
parentnode = None # If the passed xpath snippet (nodename) exists, return the node
# If it doesn't exist, create it, and return the new node
nodelist = xpath.split("/") # If nodename is a node property, we can handle it up front
for nodename in nodelist:
if not nodename:
continue
# If xpath is a node property, set it and move on
if nodename.startswith("@"): if nodename.startswith("@"):
nodename = nodename.strip("@") nodename = nodename.strip("@")
parentnode = parentnode.setProp(nodename, "") return parentnode.setProp(nodename, ""), parentpath
continue
if not parentpath: if not parentpath:
parentpath = nodename parentpath = nodename
else: else:
parentpath += "/%s" % nodename parentpath += "/%s" % nodename
# Node found, nothing to create for now # See if the xpath node already exists
node = _get_xpath_node(ctx, parentpath) node = _get_xpath_node(ctx, parentpath)
if node: if node:
parentnode = node # xpath node already exists, so we don't need to create anything
continue return node, parentpath
# If we don't have a parentnode by this point, the root of the
# xpath didn't find anything. Usually a coding error
if not parentnode: if not parentnode:
raise RuntimeError("Could not find XML root node") raise RuntimeError("Could not find XML root node")
# Remove conditional xpath elements for node creation # Remove conditional xpath elements for node creation. We preserved
# them up until this point since it was needed for proper xpath
# lookup, but they aren't valid syntax when creating the node
if nodename.count("["): if nodename.count("["):
nodename = nodename[:nodename.index("[")] nodename = nodename[:nodename.index("[")]
newnode = libxml2.newNode(nodename) newnode = libxml2.newNode(nodename)
parentnode = _add_pretty_child(parentnode, newnode) return _add_pretty_child(parentnode, newnode), parentpath
# Split the xpath and lookup/create each individual piece
parentpath = None
parentnode = None
for nodename in xpath.split("/"):
parentnode, parentpath = _handle_node(nodename, parentnode, parentpath)
return parentnode return parentnode