python - finding elements by attribute with lxml -

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i need parse xml file extract data. need elements attributes, here's example of document:

<root>     <articles>         <article type="news">              <content>some text</content>         </article>         <article type="info">              <content>some text</content>         </article>         <article type="news">              <content>some text</content>         </article>     </articles> </root>

here article type "news". what's efficient , elegant way lxml?

i tried find method it's not nice:

from lxml import etree f = etree.parse("myfile") root = f.getroot() articles = root.getchildren()[0] article_list = articles.findall('article') article in article_list:     if "type" in article.keys():         if article.attrib['type'] == 'news':             content = article.find('content')             content = content.text

you can use xpath, e.g. root.xpath("//article[@type='news']")

this xpath expression return list of <article/> elements "type" attributes value "news". can iterate on want, or pass wherever.

to text content, can extend xpath so:

root = etree.fromstring(""" <root>     <articles>         <article type="news">              <content>some text</content>         </article>         <article type="info">              <content>some text</content>         </article>         <article type="news">              <content>some text</content>         </article>     </articles> </root> """)  print root.xpath("//article[@type='news']/content/text()")

and output ['some text', 'some text']. or if wanted content elements, "//article[@type='news']/content" -- , on.


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