This pull request updates the `HTMLHeaderTextSplitter` by replacing the
`split_text_from_file` method's implementation. The original method used
`lxml` and XSLT for processing HTML files, which caused
`lxml.etree.xsltapplyerror maxhead` when handling large HTML documents
due to limitations in the XSLT processor. Fixes#13149
By switching to BeautifulSoup (`bs4`), we achieve:
- **Improved Performance and Reliability:** BeautifulSoup efficiently
processes large HTML files without the errors associated with `lxml` and
XSLT.
- **Simplified Dependencies:** Removes the dependency on `lxml` and
external XSLT files, relying instead on the widely used `beautifulsoup4`
library.
- **Maintained Functionality:** The new method replicates the original
behavior, ensuring compatibility with existing code and preserving the
extraction of content and metadata.
**Issue:**
This change addresses issues related to processing large HTML files with
the existing `HTMLHeaderTextSplitter` implementation. It resolves
problems where users encounter lxml.etree.xsltapplyerror maxhead due to
large HTML documents.
**Dependencies:**
- **BeautifulSoup (`beautifulsoup4`):** The `beautifulsoup4` library is
now used for parsing HTML content.
- Installation: `pip install beautifulsoup4`
**Code Changes:**
Updated the `split_text_from_file` method in `HTMLHeaderTextSplitter` as
follows:
```python
def split_text_from_file(self, file: Any) -> List[Document]:
"""Split HTML file using BeautifulSoup.
Args:
file: HTML file path or file-like object.
Returns:
List of Document objects with page_content and metadata.
"""
from bs4 import BeautifulSoup
from langchain.docstore.document import Document
import bs4
# Read the HTML content from the file or file-like object
if isinstance(file, str):
with open(file, 'r', encoding='utf-8') as f:
html_content = f.read()
else:
# Assuming file is a file-like object
html_content = file.read()
# Parse the HTML content using BeautifulSoup
soup = BeautifulSoup(html_content, 'html.parser')
# Extract the header tags and their corresponding metadata keys
headers_to_split_on = [tag[0] for tag in self.headers_to_split_on]
header_mapping = dict(self.headers_to_split_on)
documents = []
# Find the body of the document
body = soup.body if soup.body else soup
# Find all header tags in the order they appear
all_headers = body.find_all(headers_to_split_on)
# If there's content before the first header, collect it
first_header = all_headers[0] if all_headers else None
if first_header:
pre_header_content = ''
for elem in first_header.find_all_previous():
if isinstance(elem, bs4.Tag):
text = elem.get_text(separator=' ', strip=True)
if text:
pre_header_content = text + ' ' + pre_header_content
if pre_header_content.strip():
documents.append(Document(
page_content=pre_header_content.strip(),
metadata={} # No metadata since there's no header
))
else:
# If no headers are found, return the whole content
full_text = body.get_text(separator=' ', strip=True)
if full_text.strip():
documents.append(Document(
page_content=full_text.strip(),
metadata={}
))
return documents
# Process each header and its associated content
for header in all_headers:
current_metadata = {}
header_name = header.name
header_text = header.get_text(separator=' ', strip=True)
current_metadata[header_mapping[header_name]] = header_text
# Collect all sibling elements until the next header of the same or higher level
content_elements = []
for sibling in header.find_next_siblings():
if sibling.name in headers_to_split_on:
# Stop at the next header
break
if isinstance(sibling, bs4.Tag):
content_elements.append(sibling)
# Get the text content of the collected elements
current_content = ''
for elem in content_elements:
text = elem.get_text(separator=' ', strip=True)
if text:
current_content += text + ' '
# Create a Document if there is content
if current_content.strip():
documents.append(Document(
page_content=current_content.strip(),
metadata=current_metadata.copy()
))
else:
# If there's no content, but we have metadata, still create a Document
documents.append(Document(
page_content='',
metadata=current_metadata.copy()
))
return documents
```
---------
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
**Description:**
With current HTML splitters, they rely on secondary use of the
`RecursiveCharacterSplitter` to further chunk the document into
manageable chunks. The issue with this is it fails to maintain important
structures such as tables, lists, etc within HTML.
This Implementation of a HTML splitter, allows the user to define a
maximum chunk size, HTML elements to preserve in full, options to
preserve `<a>` href links in the output and custom handlers.
The core splitting begins with headers, similar to `HTMLHeaderSplitter`.
If these sections exceed the length of the `max_chunk_size` further
recursive splitting is triggered. During this splitting, elements listed
to preserve, will be excluded from the splitting process. This can cause
chunks to be slightly larger then the max size, depending on preserved
length. However, all contextual relevance of the preserved item remains
intact.
**Custom Handlers**: Sometimes, companies such as Atlassian have custom
HTML elements, that are not parsed by default with `BeautifulSoup`.
Custom handlers allows a user to provide a function to be ran whenever a
specific html tag is encountered. This allows the user to preserve and
gather information within custom html tags that `bs4` will potentially
miss during extraction.
**Dependencies:** User will need to install `bs4` in their project to
utilise this class
I have also added in `how_to` and unit tests, which require `bs4` to
run, otherwise they will be skipped.
Flowchart of process:
---------
Co-authored-by: Bagatur <baskaryan@gmail.com>
Co-authored-by: Chester Curme <chester.curme@gmail.com>
- **Description:**
This PR resolves an issue with the
`ExperimentalMarkdownSyntaxTextSplitter` class, which retains the
internal state across multiple calls to the `split_text` method. This
behaviour caused an unintended accumulation of chunks in `self`
variables, leading to incorrect outputs when processing multiple
Markdown files sequentially.
- Modified `libs\text-splitters\langchain_text_splitters\markdown.py` to
reset the relevant internal attributes at the start of each `split_text`
invocation. This ensures each call processes the input independently.
- Added unit tests in
`libs\text-splitters\tests\unit_tests\test_text_splitters.py` to verify
the fix and ensure the state does not persist across calls.
- **Issue:**
Fixes [#26440](https://github.com/langchain-ai/langchain/issues/26440).
- **Dependencies:**
No additional dependencies are introduced with this change.
- [x] Unit tests were added to verify the changes.
- [x] Updated documentation where necessary.
- [x] Ran `make format`, `make lint`, and `make test` to ensure
compliance with project standards.
---------
Co-authored-by: Angel Chen <angelchen396@gmail.com>
Co-authored-by: Chester Curme <chester.curme@gmail.com>
This PR closes#27781
# Problem
The current implementation of `NLTKTextSplitter` is using
`sent_tokenize`. However, this `sent_tokenize` doesn't handle chars
between 2 tokenized sentences... hence, this behavior throws errors when
we are using `add_start_index=True`, as described in issue #27781. In
particular:
```python
from nltk.tokenize import sent_tokenize
output1 = sent_tokenize("Innovation drives our success. Collaboration fosters creative solutions. Efficiency enhances data management.", language="english")
print(output1)
output2 = sent_tokenize("Innovation drives our success. Collaboration fosters creative solutions. Efficiency enhances data management.", language="english")
print(output2)
>>> ['Innovation drives our success.', 'Collaboration fosters creative solutions.', 'Efficiency enhances data management.']
>>> ['Innovation drives our success.', 'Collaboration fosters creative solutions.', 'Efficiency enhances data management.']
```
# Solution
With this new `use_span_tokenize` parameter, we can use NLTK to create
sentences (with `span_tokenize`), but also add extra chars to be sure
that we still can map the chunks to the original text.
---------
Co-authored-by: Erick Friis <erick@langchain.dev>
Co-authored-by: Erick Friis <erickfriis@gmail.com>
Previously, regardless of whether or not strip_whitespace was set to
true or false, the strip text method in the SpacyTextSplitter class used
`sent.text` to get the sentence. I modified this to include a ternary
such that if strip_whitespace is false, it uses `sent.text_with_ws`
I also modified the project.toml to include the spacy pipeline package
and to lock the numpy version, as higher versions break spacy.
- **Issue:** N/a
- **Dependencies:** None
Thank you for contributing to LangChain!
**Description:** Noticed an issue with when I was calling
`RecursiveJsonSplitter().split_json()` multiple times that I was getting
weird results. I found an issue where `chunks` list in the `_json_split`
method. If chunks is not provided when _json_split (which is the case
when split_json calls _json_split) then the same list is used for
subsequent calls to `_json_split`.
You can see this in the test case i also added to this commit.
Output should be:
```
[{'a': 1, 'b': 2}]
[{'c': 3, 'd': 4}]
```
Instead you get:
```
[{'a': 1, 'b': 2}]
[{'a': 1, 'b': 2, 'c': 3, 'd': 4}]
```
---------
Co-authored-by: Nuno Campos <nuno@langchain.dev>
Co-authored-by: isaac hershenson <ihershenson@hmc.edu>
Co-authored-by: Isaac Francisco <78627776+isahers1@users.noreply.github.com>
#### Description
This MR defines a `ExperimentalMarkdownSyntaxTextSplitter` class. The
main goal is to replicate the functionality of the original
`MarkdownHeaderTextSplitter` which extracts the header stack as metadata
but with one critical difference: it keeps the whitespace of the
original text intact.
This draft reimplements the `MarkdownHeaderTextSplitter` with a very
different algorithmic approach. Instead of marking up each line of the
text individually and aggregating them back together into chunks, this
method builds each chunk sequentially and applies the metadata to each
chunk. This makes the implementation simpler. However, since it's
designed to keep white space intact its not a full drop in replacement
for the original. Since it is a radical implementation change to the
original code and I would like to get feedback to see if this is a
worthwhile replacement, should be it's own class, or is not a good idea
at all.
Note: I implemented the `return_each_line` parameter but I don't think
it's a necessary feature. I'd prefer to remove it.
This implementation also adds the following additional features:
- Splits out code blocks and includes the language in the `"Code"`
metadata key
- Splits text on the horizontal rule `---` as well
- The `headers_to_split_on` parameter is now optional - with sensible
defaults that can be overridden.
#### Issue
Keeping the whitespace keeps the paragraphs structure and the formatting
of the code blocks intact which allows the caller much more flexibility
in how they want to further split the individuals sections of the
resulting documents. This addresses the issues brought up by the
community in the following issues:
- https://github.com/langchain-ai/langchain/issues/20823
- https://github.com/langchain-ai/langchain/issues/19436
- https://github.com/langchain-ai/langchain/issues/22256
#### Dependencies
N/A
#### Twitter handle
@RyanElston
---------
Co-authored-by: isaac hershenson <ihershenson@hmc.edu>
Update former pull request:
https://github.com/langchain-ai/langchain/pull/22654.
Modified `langchain_text_splitters.HTMLSectionSplitter`, where in the
latest version `dict` data structure is used to store sections from a
html document, in function `split_html_by_headers`. The header/section
element names serve as dict keys. This can be a problem when duplicate
header/section element names are present in a single html document.
Latter ones can replace former ones with the same name. Therefore some
contents can be miss after html text splitting is conducted.
Using a list to store sections can hopefully solve the problem. A Unit
test considering duplicate header names has been added.
---------
Co-authored-by: Bagatur <baskaryan@gmail.com>
## Description
This PR allows passing the HTMLSectionSplitter paths to xslt files. It
does so by fixing two trivial bugs with how passed paths were being
handled. It also changes the default value of the param `xslt_path` to
`None` so the special case where the file was part of the langchain
package could be handled.
## Issue
#22175
**Description:** Added extra functionality to `CharacterTextSplitter`,
`TextSplitter` classes.
The user can select whether to append the separator to the previous
chunk with `keep_separator='end' ` or else prepend to the next chunk.
Previous functionality prepended by default to next chunk.
**Issue:** Fixes#20908
---------
Co-authored-by: Bagatur <22008038+baskaryan@users.noreply.github.com>
Description: MarkdownHeaderTextSplitter Fails to Parse Headers with
non-printable characters. more #20643
The following is the official test case. Just replacing `# Foo\n\n` with
`\ufeff# Foo\n\n` will cause the test case to fail.
chunk metadata is empty
```python
def test_md_header_text_splitter_1() -> None:
"""Test markdown splitter by header: Case 1."""
markdown_document = (
"\ufeff# Foo\n\n"
" ## Bar\n\n"
"Hi this is Jim\n\n"
"Hi this is Joe\n\n"
" ## Baz\n\n"
" Hi this is Molly"
)
headers_to_split_on = [
("#", "Header 1"),
("##", "Header 2"),
]
markdown_splitter = MarkdownHeaderTextSplitter(
headers_to_split_on=headers_to_split_on,
)
output = markdown_splitter.split_text(markdown_document)
expected_output = [
Document(
page_content="Hi this is Jim \nHi this is Joe",
metadata={"Header 1": "Foo", "Header 2": "Bar"},
),
Document(
page_content="Hi this is Molly",
metadata={"Header 1": "Foo", "Header 2": "Baz"},
),
]
assert output == expected_output
```
twitter: @coolbeevip
Co-authored-by: Bagatur <22008038+baskaryan@users.noreply.github.com>
- **Description:** Complete the support for Lua code in
langchain.text_splitter module.
- **Dependencies:** No
- **Twitter handle:** @saberuster
If no one reviews your PR within a few days, please @-mention one of
baskaryan, efriis, eyurtsev, hwchase17.
---------
Co-authored-by: Bagatur <baskaryan@gmail.com>
- **Description:** the layout of html pages can be variant based on the
bootstrap framework or the styles of the pages. So we need to have a
splitter to transform the html tags to a proper layout and then split
the html content based on the provided list of tags to determine its
html sections. We are using BS4 library along with xslt structure to
split the html content using an section aware approach.
- **Dependencies:** No new dependencies
- **Twitter handle:** @m_setayesh
Please make sure your PR is passing linting and testing before
submitting. Run `make format`, `make lint` and `make test` from the root
of the package you've modified to check this locally.
See contribution guidelines for more information on how to write/run
tests, lint, etc: https://python.langchain.com/docs/contributing/
If you're adding a new integration, please include:
1. a test for the integration, preferably unit tests that do not rely on
network access,
2. an example notebook showing its use. It lives in
`docs/docs/integrations` directory.
If no one reviews your PR within a few days, please @-mention one of
@baskaryan, @eyurtsev, @hwchase17.
-->
---------
Co-authored-by: Bagatur <baskaryan@gmail.com>
- **Description:** Haskell language support added in text_splitter
module
- **Dependencies:** No
- **Twitter handle:** @nisargtr
If no one reviews your PR within a few days, please @-mention one of
@baskaryan, @eyurtsev, @hwchase17.
---------
Co-authored-by: Bagatur <baskaryan@gmail.com>
