changedetection.io/backend/html_tools.py

from bs4 import BeautifulSoup


# Given a CSS Rule, and a blob of HTML, return the blob of HTML that matches
def css_filter(css_filter, html_content):
    soup = BeautifulSoup(html_content, "html.parser")
    html_block = ""
    for item in soup.select(css_filter, separator=""):
        html_block += str(item)

    return html_block + "\n"


# Extract/find element
def extract_element(find='title', html_content=''):

    #Re #106, be sure to handle when its not found
    element_text = None

    soup = BeautifulSoup(html_content, 'html.parser')
    result = soup.find(find)
    if result and result.string:
        element_text = result.string.strip()

    return element_text