dify/api/core/spiltter/fixed_text_splitter.py
John Wang 3241e4015b
feat: upgrade langchain (#430)
Co-authored-by: jyong <718720800@qq.com>
2023-06-25 16:49:14 +08:00

69 lines
2.3 KiB
Python

"""Functionality for splitting text."""
from __future__ import annotations
from typing import (
Any,
List,
Optional,
)
from langchain.text_splitter import RecursiveCharacterTextSplitter
class FixedRecursiveCharacterTextSplitter(RecursiveCharacterTextSplitter):
def __init__(self, fixed_separator: str = "\n\n", separators: Optional[List[str]] = None, **kwargs: Any):
"""Create a new TextSplitter."""
super().__init__(**kwargs)
self._fixed_separator = fixed_separator
self._separators = separators or ["\n\n", "\n", " ", ""]
def split_text(self, text: str) -> List[str]:
"""Split incoming text and return chunks."""
if self._fixed_separator:
chunks = text.split(self._fixed_separator)
else:
chunks = list(text)
final_chunks = []
for chunk in chunks:
if self._length_function(chunk) > self._chunk_size:
final_chunks.extend(self.recursive_split_text(chunk))
else:
final_chunks.append(chunk)
return final_chunks
def recursive_split_text(self, text: str) -> List[str]:
"""Split incoming text and return chunks."""
final_chunks = []
# Get appropriate separator to use
separator = self._separators[-1]
for _s in self._separators:
if _s == "":
separator = _s
break
if _s in text:
separator = _s
break
# Now that we have the separator, split the text
if separator:
splits = text.split(separator)
else:
splits = list(text)
# Now go merging things, recursively splitting longer texts.
_good_splits = []
for s in splits:
if self._length_function(s) < self._chunk_size:
_good_splits.append(s)
else:
if _good_splits:
merged_text = self._merge_splits(_good_splits, separator)
final_chunks.extend(merged_text)
_good_splits = []
other_info = self.recursive_split_text(s)
final_chunks.extend(other_info)
if _good_splits:
merged_text = self._merge_splits(_good_splits, separator)
final_chunks.extend(merged_text)
return final_chunks