Specific pathing to find XML elements using minidom in Python
As per this thread, I am using xml.dom.minidom to do some very basic XML traversing, read-only.
What confuses me is why its getElementsByTagName is finding nodes several hierarchy levels deep without explicitly supplying it with their exact path.
XML:
<data>
<items>
<item name="item1"></item>
<item name="item2"></item>
<item name="item3"></item>
<item name="item4"></item>
</items>
<secondSetOfItems>
<item name="item5"></item>
<item name="item6"></item>
<item name="item7"></item>
<item name="item8"></item>
</secondSetOfItems>
</data>
Python code:
xmldoc = minidom.parse('sampleXML.xml')
items = xmldoc.getElementsByTagName('item')
for item in items:
print item.attributes['name'].value
Prints:
item1
item2
item3
item4
item5
item6
item7
item8
What bothers me is that it implicitly finds tags named item under both data->items as well as data->secondSetOfItems .
How do I make it follow an explicit path and only extract items under one of the two categories? Eg under data->secondSetOfItems :
item5
item6
item7
item8
If you want to get items from a specific category, you can do so by grabbing the parent element first.
For example:
Code :
xmldoc = minidom.parse('sampleXML.xml')
#Grab the first occurence of the "secondSetOfItems" element
second_items = xmldoc.getElementsByTagName("secondSetOfItems")[0]
item_list = second_items.getElementsByTagName("item")
for item in item_list:
print item.attributes['name'].value
Output :
item5
item6
item7
item8
this is the declared behavior of getElementsByTagName
Search for all descendants (direct children, children's children, etc.) with a particular element type name.
some wrote a "filter" on it, see this answer
seem to me that minidom is too simple, consider using lxml xpath:
tree.xpath('//secondSetOfItems/item/@name')
or BeautifulSoup findAll:
data.secondSetOfItems.item.findAll('name')
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