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Create a table of contents from HTML using Python

I am trying to generate a table of contents from an HTML block (not a complete file - only content) based on <h2>and tags <h3>.

My plan so far has been as follows:

  • Retrieve the list of headers with beautifulsoup

  • Use a regular expression for content to place anchor links before / inside title tags (so that the user can click on the table of contents). Perhaps there is a method to replace inside beautifulsoup?

  • Display a nested list of heading links in a predefined location.

It sounds easy when I say it like that, but it hurts a little in the rear.

Is there something that does all this for me at a time, so I don’t waste the next couple of hours inventing the wheel?

Example:

<p>This is an introduction</p>

<h2>This is a sub-header</h2>
<p>...</p>

<h3>This is a sub-sub-header</h3>
<p>...</p>

<h2>This is a sub-header</h2>
<p>...</p>
+5
3

lxml.html.

+1

:

soup = BeautifulSoup(html)

toc = []
header_id = 1
current_list = toc
previous_tag = None

for header in soup.findAll(['h2', 'h3']):
    header['id'] = header_id

    if previous_tag == 'h2' and header.name == 'h3':
        current_list = []
    elif previous_tag == 'h3' and header.name == 'h2':
        toc.append(current_list)
        current_list = toc

    current_list.append((header_id, header.string))

    header_id += 1
    previous_tag = header.name

if current_list != toc:
    toc.append(current_list)


def list_to_html(lst):
    result = ["<ul>"]
    for item in lst:
        if isinstance(item, list):
            result.append(list_to_html(item))
        else:
            result.append('<li><a href="#%s">%s</a></li>' % item)
    result.append("</ul>")
    return "\n".join(result)

# Table of contents
print list_to_html(toc)

# Modified HTML
print soup
+2

How to create a table of contents for HTML text in Python?

But I think you're on the right track, and it will be fun to reinvent the wheel.

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