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pythonhtml-parsingbeautifulsoup

How to save back changes made to a HTML file using BeautifulSoup in Python?


I have the script below, which modifies href attributes in an HTML file (in the future, it will be a list of HTML files in a directory). Using BeautifulSoup I managed to access the tag values and modify them like I want, but I don't know how to save back the changes made to the file.

import os
import re
from bs4 import BeautifulSoup


htmlDoc = open('adding_computer_c.html',"r+")
soup = BeautifulSoup(htmlDoc)

replacements= [ ('_', '-'), ('../tasks/', prefixUrl), ('../concepts/', prefixUrl) ]

for link in soup.findAll('a', attrs={'href': re.compile("../")}):


    newlink=str(link)

    for k, v in replacements:

        newlink = newlink.replace(k, v)

    extrachars=newlink[newlink.find("."):newlink.find(">")]
    newlink=newlink.replace(extrachars,'')


    link=newlink
    print(link)
    ##How do I save the link I have modified back to the HTML file?

print(soup)##prints the original html tree

htmlDoc.close()

Solution

  • newlink = link['href']
    # .. make replacements
    link['href'] = newlink # store it back
    

    Now print(soup.prettify()) will show changed links. To save the changes to a file:

    htmlDoc.close()
    
    html = soup.prettify("utf-8")
    with open("output.html", "wb") as file:
        file.write(html)
    

    To preserve original character encoding of the document, you could use soup.original_encoding instead of "utf-8". See Encodings.