Module document_cleaner

DocumentCleaner

Cleans the text in the documents.

It removes extra whitespaces, empty lines, specified substrings, regexes, page headers and footers (in this order).

Usage example:

from haystack import Document
from haystack.components.preprocessors import DocumentCleaner

doc = Document(content="This   is  a  document  to  clean\n\n\nsubstring to remove")

cleaner = DocumentCleaner(remove_substrings = ["substring to remove"])
result = cleaner.run(documents=[doc])

assert result["documents"][0].content == "This is a document to clean "

DocumentCleaner.__init__

def __init__(remove_empty_lines: bool = True,
             remove_extra_whitespaces: bool = True,
             remove_repeated_substrings: bool = False,
             keep_id: bool = False,
             remove_substrings: Optional[List[str]] = None,
             remove_regex: Optional[str] = None,
             unicode_normalization: Optional[Literal["NFC", "NFKC", "NFD",
                                                     "NFKD"]] = None,
             ascii_only: bool = False)

Initialize DocumentCleaner.

Arguments:

• remove_empty_lines: If True, removes empty lines.
• remove_extra_whitespaces: If True, removes extra whitespaces.
• remove_repeated_substrings: If True, removes repeated substrings (headers and footers) from pages. Pages must be separated by a form feed character "\f", which is supported by TextFileToDocument and AzureOCRDocumentConverter.
• remove_substrings: List of substrings to remove from the text.
• remove_regex: Regex to match and replace substrings by "".
• keep_id: If True, keeps the IDs of the original documents.
• unicode_normalization: Unicode normalization form to apply to the text. Note: This will run before any other steps.
• ascii_only: Whether to convert the text to ASCII only. Will remove accents from characters and replace them with ASCII characters. Other non-ASCII characters will be removed. Note: This will run before any pattern matching or removal.

DocumentCleaner.run

@component.output_types(documents=List[Document])
def run(documents: List[Document])

Cleans up the documents.

Arguments:

• documents: List of Documents to clean.

Raises:

• TypeError: if documents is not a list of Documents.

Returns:

A dictionary with the following key:

• documents: List of cleaned Documents.

Module document_splitter

DocumentSplitter

Splits long documents into smaller chunks.

This is a common preprocessing step during indexing. It helps Embedders create meaningful semantic representations and prevents exceeding language model context limits.

The DocumentSplitter is compatible with the following DocumentStores:

• Astra
• Chroma limited support, overlapping information is not stored
• Elasticsearch
• OpenSearch
• Pgvector
• Pinecone limited support, overlapping information is not stored
• Qdrant
• Weaviate

Usage example

from haystack import Document
from haystack.components.preprocessors import DocumentSplitter

doc = Document(content="Moonlight shimmered softly, wolves howled nearby, night enveloped everything.")

splitter = DocumentSplitter(split_by="word", split_length=3, split_overlap=0)
result = splitter.run(documents=[doc])

DocumentSplitter.__init__

def __init__(split_by: Literal["function", "page", "passage", "period", "word",
                               "line", "sentence"] = "word",
             split_length: int = 200,
             split_overlap: int = 0,
             split_threshold: int = 0,
             splitting_function: Optional[Callable[[str], List[str]]] = None,
             respect_sentence_boundary: bool = False,
             language: Language = "en",
             use_split_rules: bool = True,
             extend_abbreviations: bool = True)

Initialize DocumentSplitter.

Arguments:

• split_by: The unit for splitting your documents. Choose from:
• word for splitting by spaces (" ")
• period for splitting by periods (".")
• page for splitting by form feed ("\f")
• passage for splitting by double line breaks ("\n\n")
• line for splitting each line ("\n")
• sentence for splitting by NLTK sentence tokenizer
• split_length: The maximum number of units in each split.
• split_overlap: The number of overlapping units for each split.
• split_threshold: The minimum number of units per split. If a split has fewer units than the threshold, it's attached to the previous split.
• splitting_function: Necessary when split_by is set to "function". This is a function which must accept a single str as input and return a list of str as output, representing the chunks after splitting.
• respect_sentence_boundary: Choose whether to respect sentence boundaries when splitting by "word". If True, uses NLTK to detect sentence boundaries, ensuring splits occur only between sentences.
• language: Choose the language for the NLTK tokenizer. The default is English ("en").
• use_split_rules: Choose whether to use additional split rules when splitting by sentence.
• extend_abbreviations: Choose whether to extend NLTK's PunktTokenizer abbreviations with a list of curated abbreviations, if available. This is currently supported for English ("en") and German ("de").

DocumentSplitter.warm_up

def warm_up()

Warm up the DocumentSplitter by loading the sentence tokenizer.

DocumentSplitter.run

@component.output_types(documents=List[Document])
def run(documents: List[Document])

Split documents into smaller parts.

Splits documents by the unit expressed in split_by, with a length of split_length and an overlap of split_overlap.

Arguments:

• documents: The documents to split.

Raises:

• TypeError: if the input is not a list of Documents.
• ValueError: if the content of a document is None.

Returns:

A dictionary with the following key:

• documents: List of documents with the split texts. Each document includes:
• A metadata field source_id to track the original document.
• A metadata field page_number to track the original page number.
• All other metadata copied from the original document.

DocumentSplitter.to_dict

def to_dict() -> Dict[str, Any]

Serializes the component to a dictionary.

DocumentSplitter.from_dict

@classmethod
def from_dict(cls, data: Dict[str, Any]) -> "DocumentSplitter"

Deserializes the component from a dictionary.

Module nltk_document_splitter

NLTKDocumentSplitter

NLTKDocumentSplitter.__init__

def __init__(split_by: Literal["word", "sentence", "page", "passage",
                               "function"] = "word",
             split_length: int = 200,
             split_overlap: int = 0,
             split_threshold: int = 0,
             respect_sentence_boundary: bool = False,
             language: Language = "en",
             use_split_rules: bool = True,
             extend_abbreviations: bool = True,
             splitting_function: Optional[Callable[[str], List[str]]] = None)

Splits your documents using NLTK to respect sentence boundaries.

Initialize the NLTKDocumentSplitter.

Arguments:

• split_by: Select the unit for splitting your documents. Choose from word for splitting by spaces (" "), sentence for splitting by NLTK sentence tokenizer, page for splitting by the form feed ("\f") or passage for splitting by double line breaks ("\n\n").
• split_length: The maximum number of units in each split.
• split_overlap: The number of overlapping units for each split.
• split_threshold: The minimum number of units per split. If a split has fewer units than the threshold, it's attached to the previous split.
• respect_sentence_boundary: Choose whether to respect sentence boundaries when splitting by "word". If True, uses NLTK to detect sentence boundaries, ensuring splits occur only between sentences.
• language: Choose the language for the NLTK tokenizer. The default is English ("en").
• use_split_rules: Choose whether to use additional split rules when splitting by sentence.
• extend_abbreviations: Choose whether to extend NLTK's PunktTokenizer abbreviations with a list of curated abbreviations, if available. This is currently supported for English ("en") and German ("de").
• splitting_function: Necessary when split_by is set to "function". This is a function which must accept a single str as input and return a list of str as output, representing the chunks after splitting.

NLTKDocumentSplitter.warm_up

def warm_up()

Warm up the NLTKDocumentSplitter by loading the sentence tokenizer.

NLTKDocumentSplitter.run

@component.output_types(documents=List[Document])
def run(documents: List[Document]) -> Dict[str, List[Document]]

Split documents into smaller parts.

Splits documents by the unit expressed in split_by, with a length of split_length and an overlap of split_overlap.

Arguments:

• documents: The documents to split.

Raises:

• TypeError: if the input is not a list of Documents.
• ValueError: if the content of a document is None.

Returns:

A dictionary with the following key:

• documents: List of documents with the split texts. Each document includes:
• A metadata field source_id to track the original document.
• A metadata field page_number to track the original page number.
• All other metadata copied from the original document.

NLTKDocumentSplitter.to_dict

def to_dict() -> Dict[str, Any]

Serializes the component to a dictionary.

NLTKDocumentSplitter.from_dict

@classmethod
def from_dict(cls, data: Dict[str, Any]) -> "DocumentSplitter"

Deserializes the component from a dictionary.

Module recursive_splitter

RecursiveDocumentSplitter

Recursively chunk text into smaller chunks.

This component is used to split text into smaller chunks, it does so by recursively applying a list of separators to the text.

The separators are applied in the order they are provided, typically this is a list of separators that are applied in a specific order, being the last separator the most specific one.

Each separator is applied to the text, it then checks each of the resulting chunks, it keeps the chunks that are within the chunk_size, for the ones that are larger than the chunk_size, it applies the next separator in the list to the remaining text.

This is done until all chunks are smaller than the chunk_size parameter.

Example:

```python
from haystack import Document
from haystack.components.preprocessors import RecursiveDocumentSplitter

chunker = RecursiveDocumentSplitter(split_length=260, split_overlap=0, separators=["

", " ", ".", " "]) text = '''Artificial intelligence (AI) - Introduction

AI, in its broadest sense, is intelligence exhibited by machines, particularly computer systems.
AI technology is widely used throughout industry, government, and science. Some high-profile applications include advanced web search engines; recommendation systems; interacting via human speech; autonomous vehicles; generative and creative tools; and superhuman play and analysis in strategy games.'''
chunker.warm_up()
doc = Document(content=text)
doc_chunks = chunker.run([doc])
print(doc_chunks["documents"])
>[
>Document(id=..., content: 'Artificial intelligence (AI) - Introduction

', meta: {'original_id': '65167a9823dd883de577e828ca4fd529e6f7241f0ff616acfce454d808478951', 'split_id': 0, 'split_idx_start': 0, '_split_overlap': []}) >Document(id=..., content: 'AI, in its broadest sense, is intelligence exhibited by machines, particularly computer systems. ', meta: {'original_id': '65167a9823dd883de577e828ca4fd529e6f7241f0ff616acfce454d808478951', 'split_id': 1, 'split_idx_start': 45, '_split_overlap': []}) >Document(id=..., content: 'AI technology is widely used throughout industry, government, and science.', meta: {'original_id': '65167a9823dd883de577e828ca4fd529e6f7241f0ff616acfce454d808478951', 'split_id': 2, 'split_idx_start': 142, '_split_overlap': []}) >Document(id=..., content: ' Some high-profile applications include advanced web search engines; recommendation systems; interac...', meta: {'original_id': '65167a9823dd883de577e828ca4fd529e6f7241f0ff616acfce454d808478951', 'split_id': 3, 'split_idx_start': 216, '_split_overlap': []}) >] ```

RecursiveDocumentSplitter.__init__

def __init__(*,
             split_length: int = 200,
             split_overlap: int = 0,
             split_unit: Literal["word", "char"] = "word",
             separators: Optional[List[str]] = None,
             sentence_splitter_params: Optional[Dict[str, Any]] = None)

Initializes a RecursiveDocumentSplitter.

:param split_length: The maximum length of each chunk by default in words, but can be in characters. See the split_units parameter. :param split_overlap: The number of characters to overlap between consecutive chunks. :param split_unit: The unit of the split_length parameter. It can be either "word" or "char". :param separators: An optional list of separator strings to use for splitting the text. The string separators will be treated as regular expressions unless the separator is "sentence", in that case the text will be split into sentences using a custom sentence tokenizer based on NLTK. See: haystack.components.preprocessors.sentence_tokenizer.SentenceSplitter. If no separators are provided, the default separators ["

", "sentence", " ", " "] are used. :param sentence_splitter_params: Optional parameters to pass to the sentence tokenizer. See: haystack.components.preprocessors.sentence_tokenizer.SentenceSplitter for more information.

    :raises ValueError: If the overlap is greater than or equal to the chunk size or if the overlap is negative, or
                        if any separator is not a string.

RecursiveDocumentSplitter.warm_up

def warm_up() -> None

Warm up the sentence tokenizer.

RecursiveDocumentSplitter.run

@component.output_types(documents=List[Document])
def run(documents: List[Document]) -> Dict[str, List[Document]]

Split a list of documents into documents with smaller chunks of text.

Arguments:

• documents: List of Documents to split.

Returns:

A dictionary containing a key "documents" with a List of Documents with smaller chunks of text corresponding to the input documents.

Module text_cleaner

TextCleaner

Cleans text strings.

It can remove substrings matching a list of regular expressions, convert text to lowercase, remove punctuation, and remove numbers. Use it to clean up text data before evaluation.

Usage example

from haystack.components.preprocessors import TextCleaner

text_to_clean = "1Moonlight shimmered softly, 300 Wolves howled nearby, Night enveloped everything."

cleaner = TextCleaner(convert_to_lowercase=True, remove_punctuation=False, remove_numbers=True)
result = cleaner.run(texts=[text_to_clean])

TextCleaner.__init__

def __init__(remove_regexps: Optional[List[str]] = None,
             convert_to_lowercase: bool = False,
             remove_punctuation: bool = False,
             remove_numbers: bool = False)

Initializes the TextCleaner component.

Arguments:

• remove_regexps: A list of regex patterns to remove matching substrings from the text.
• convert_to_lowercase: If True, converts all characters to lowercase.
• remove_punctuation: If True, removes punctuation from the text.
• remove_numbers: If True, removes numerical digits from the text.

TextCleaner.run

@component.output_types(texts=List[str])
def run(texts: List[str]) -> Dict[str, Any]

Cleans up the given list of strings.

Arguments:

• texts: List of strings to clean.

Returns:

A dictionary with the following key:

• texts: the cleaned list of strings.