Module cache_checker

CacheChecker

@component
class CacheChecker()

Checks for the presence of documents in a Document Store based on a specified field in each document's metadata.

If matching documents are found, they are returned as hits. If not, the items are returned as misses, indicating they are not in the cache.

Usage example:

from haystack import Document
from haystack.document_stores.in_memory import InMemoryDocumentStore
from haystack.components.caching.cache_checker import CacheChecker

docstore = InMemoryDocumentStore()
documents = [
    Document(content="doc1", meta={"url": "https://example.com/1"}),
    Document(content="doc2", meta={"url": "https://example.com/2"}),
    Document(content="doc3", meta={"url": "https://example.com/1"}),
    Document(content="doc4", meta={"url": "https://example.com/2"}),
]
docstore.write_documents(documents)
checker = CacheChecker(docstore, cache_field="url")
results = checker.run(items=["https://example.com/1", "https://example.com/5"])
assert results == {"hits": [documents[0], documents[2]], "misses": ["https://example.com/5"]}

CacheChecker.__init__

def __init__(document_store: DocumentStore, cache_field: str)

Create a CacheChecker component.

Arguments:

• document_store: Document store to check.
• cache_field: Name of the Document metadata field to check for cache hits.

CacheChecker.to_dict

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

Serializes the component to a dictionary.

Returns:

Dictionary with serialized data.

CacheChecker.from_dict

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

Deserializes the component from a dictionary.

Arguments:

• data: Dictionary to deserialize from.

Returns:

Deserialized component.

CacheChecker.run

@component.output_types(hits=List[Document], misses=List)
def run(items: List[Any])

Checks if any document associated with the specified cache field

is already present in the store.

Arguments:

• items: Values to be checked against the cache field.

Returns:

A dictionary with two keys:

• hits - Documents that matched with any of the items.
• misses - Items that were not present in any documents.