|  |
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This method reconstructs the node element
and its children.
# - - - L o c . r e a d N o d e
@staticmethod
def readNode(node):
"""Convert XML to a Loc instance.
"""
First we'll create a new Loc instance
with attribute values taken from the node.
See Section 10.1, “Loc.__init__(): Constructor”.
#-- 1 --
# [ code := rnc.CODE_A attribute from node
# name := rnc.NAME_A attribute from node ]
code = node.attrib[rnc.CODE_A]
name = node.attrib[rnc.NAME_A]
#-- 2 --
# [ loc := a new Loc instance with code=(code) and
# name=(name) and no text ]
loc = Loc(code, name)
Next we look to see if there are any gps
children and, if so, make them into Gps
instances and add them to the Loc
instance. See Section 11.2, “Gps.readNode() (static method)”.
#-- 3 --
# [ gpsNodeList := a list containing all rnc.GPS_N
# children of node
# lastGps := None ]
gpsNodeList = node.xpath(rnc.GPS_N)
#-- 4 --
# [ if gpsNodeList is non-empty ->
# loc := loc with Gps instances added, made from
# elements of gpsNodeList
# lastGps := the last Gps instance added
# else -> I ]
for gpsNode in gpsNodeList:
lastGps = Gps.readNode(gpsNode)
loc.addGps(lastGps)
Next we check for the optional narrative describing the
location. To get around the strange way lxml handles text, we'll use the XPath
expression "text()" to get a list of all
the text node children of node, which we
will then concatenate. If any of the gps
element children have text nodes, they will not be
included. The .strip() method will delete
leading and trailing space, and if there is nothing left,
we consider that no narrative.
#-- 5 --
# [ if (node has any nonblank text children) and
# (lastGps is None) ->
# loc.text := all text children, minus leading and
# trailing space
# else if node has any nonblank text children ->
# lastGps.tail := all text children, minus leading
# and trailing space
# else -> I ]
textList = node.xpath('text()')
s = "".join(textList).strip()
if s:
loc.text = s
All that remains is to return the newly built Loc instance.
#-- 6 --
return loc