langchain/vectorstores/redis.py/Redis/add_texts
class Redis:    def add_texts(
        self,
        texts: Iterable[str],
        metadatas: Optional[List[dict]] = None,
        embeddings: Optional[List[List[float]]] = None,
        keys: Optional[List[str]] = None,
        batch_size: int = 1000,
        **kwargs: Any,
    ) -> List[str]:
        """Add more texts to the vectorstore.

        Args:
            texts (Iterable[str]): Iterable of strings/text to add to the vectorstore.
            metadatas (Optional[List[dict]], optional): Optional list of metadatas.
                Defaults to None.
            embeddings (Optional[List[List[float]]], optional): Optional pre-generated
                embeddings. Defaults to None.
            keys (Optional[List[str]], optional): Optional key values to use as ids.
                Defaults to None.
            batch_size (int, optional): Batch size to use for writes. Defaults to 1000.

        Returns:
            List[str]: List of ids added to the vectorstore
        """
        ids = []
        prefix = _redis_prefix(self.index_name)

        # Write data to redis
        pipeline = self.client.pipeline(transaction=False)
        for i, text in enumerate(texts):
            # Use provided values by default or fallback
            key = keys[i] if keys else _redis_key(prefix)
            metadata = metadatas[i] if metadatas else {}
            embedding = embeddings[i] if embeddings else self.embedding_function(text)
            pipeline.hset(
                key,
                mapping={
                    self.content_key: text,
                    self.vector_key: np.array(embedding, dtype=np.float32).tobytes(),
                    self.metadata_key: json.dumps(metadata),
                },
            )
            ids.append(key)

            # Write batch
            if i % batch_size == 0:
                pipeline.execute()

        # Cleanup final batch
        pipeline.execute()
        return ids