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| import mathimport threadingfrom collections import Counterfrom typing import Any, Optional, castfrom flask import Flask, current_appfrom core.app.app_config.entities import DatasetEntity, DatasetRetrieveConfigEntityfrom core.app.entities.app_invoke_entities import InvokeFrom, ModelConfigWithCredentialsEntityfrom core.callback_handler.index_tool_callback_handler import DatasetIndexToolCallbackHandlerfrom core.entities.agent_entities import PlanningStrategyfrom core.memory.token_buffer_memory import TokenBufferMemoryfrom core.model_manager import ModelInstance, ModelManagerfrom core.model_runtime.entities.message_entities import PromptMessageToolfrom core.model_runtime.entities.model_entities import ModelFeature, ModelTypefrom core.model_runtime.model_providers.__base.large_language_model import LargeLanguageModelfrom core.ops.entities.trace_entity import TraceTaskNamefrom core.ops.ops_trace_manager import TraceQueueManager, TraceTaskfrom core.ops.utils import measure_timefrom core.rag.data_post_processor.data_post_processor import DataPostProcessorfrom core.rag.datasource.keyword.jieba.jieba_keyword_table_handler import JiebaKeywordTableHandlerfrom core.rag.datasource.retrieval_service import RetrievalServicefrom core.rag.entities.context_entities import DocumentContextfrom core.rag.models.document import Documentfrom core.rag.rerank.rerank_type import RerankModefrom core.rag.retrieval.retrieval_methods import RetrievalMethodfrom core.rag.retrieval.router.multi_dataset_function_call_router import FunctionCallMultiDatasetRouterfrom core.rag.retrieval.router.multi_dataset_react_route import ReactMultiDatasetRouterfrom core.tools.utils.dataset_retriever.dataset_retriever_base_tool import DatasetRetrieverBaseToolfrom extensions.ext_database import dbfrom models.dataset import Dataset, DatasetQuery, DocumentSegmentfrom models.dataset import Document as DatasetDocumentfrom services.external_knowledge_service import ExternalDatasetServicedefault_retrieval_model: dict[str, Any] = {    "search_method": RetrievalMethod.SEMANTIC_SEARCH.value,    "reranking_enable": False,    "reranking_model": {"reranking_provider_name": "", "reranking_model_name": ""},    "top_k": 2,    "score_threshold_enabled": False,}class DatasetRetrieval:    def __init__(self, application_generate_entity=None):        self.application_generate_entity = application_generate_entity    def retrieve(        self,        app_id: str,        user_id: str,        tenant_id: str,        model_config: ModelConfigWithCredentialsEntity,        config: DatasetEntity,        query: str,        invoke_from: InvokeFrom,        show_retrieve_source: bool,        hit_callback: DatasetIndexToolCallbackHandler,        message_id: str,        memory: Optional[TokenBufferMemory] = None,    ) -> Optional[str]:        """        Retrieve dataset.        :param app_id: app_id        :param user_id: user_id        :param tenant_id: tenant id        :param model_config: model config        :param config: dataset config        :param query: query        :param invoke_from: invoke from        :param show_retrieve_source: show retrieve source        :param hit_callback: hit callback        :param message_id: message id        :param memory: memory        :return:        """        dataset_ids = config.dataset_ids        if len(dataset_ids) == 0:            return None        retrieve_config = config.retrieve_config        # check model is support tool calling        model_type_instance = model_config.provider_model_bundle.model_type_instance        model_type_instance = cast(LargeLanguageModel, model_type_instance)        model_manager = ModelManager()        model_instance = model_manager.get_model_instance(            tenant_id=tenant_id, model_type=ModelType.LLM, provider=model_config.provider, model=model_config.model        )        # get model schema        model_schema = model_type_instance.get_model_schema(            model=model_config.model, credentials=model_config.credentials        )        if not model_schema:            return None        planning_strategy = PlanningStrategy.REACT_ROUTER        features = model_schema.features        if features:            if ModelFeature.TOOL_CALL in features or ModelFeature.MULTI_TOOL_CALL in features:                planning_strategy = PlanningStrategy.ROUTER        available_datasets = []        for dataset_id in dataset_ids:            # get dataset from dataset id            dataset = db.session.query(Dataset).filter(Dataset.tenant_id == tenant_id, Dataset.id == dataset_id).first()            # pass if dataset is not available            if not dataset:                continue            # pass if dataset is not available            if dataset and dataset.available_document_count == 0 and dataset.provider != "external":                continue            available_datasets.append(dataset)        all_documents = []        user_from = "account" if invoke_from in {InvokeFrom.EXPLORE, InvokeFrom.DEBUGGER} else "end_user"        if retrieve_config.retrieve_strategy == DatasetRetrieveConfigEntity.RetrieveStrategy.SINGLE:            all_documents = self.single_retrieve(                app_id,                tenant_id,                user_id,                user_from,                available_datasets,                query,                model_instance,                model_config,                planning_strategy,                message_id,            )        elif retrieve_config.retrieve_strategy == DatasetRetrieveConfigEntity.RetrieveStrategy.MULTIPLE:            all_documents = self.multiple_retrieve(                app_id,                tenant_id,                user_id,                user_from,                available_datasets,                query,                retrieve_config.top_k or 0,                retrieve_config.score_threshold or 0,                retrieve_config.rerank_mode or "reranking_model",                retrieve_config.reranking_model,                retrieve_config.weights,                retrieve_config.reranking_enabled or True,                message_id,            )        dify_documents = [item for item in all_documents if item.provider == "dify"]        external_documents = [item for item in all_documents if item.provider == "external"]        document_context_list = []        retrieval_resource_list = []        # deal with external documents        for item in external_documents:            document_context_list.append(DocumentContext(content=item.page_content, score=item.metadata.get("score")))            source = {                "dataset_id": item.metadata.get("dataset_id"),                "dataset_name": item.metadata.get("dataset_name"),                "document_name": item.metadata.get("title"),                "data_source_type": "external",                "retriever_from": invoke_from.to_source(),                "score": item.metadata.get("score"),                "content": item.page_content,            }            retrieval_resource_list.append(source)        # deal with dify documents        if dify_documents:            records = RetrievalService.format_retrieval_documents(dify_documents)            if records:                for record in records:                    segment = record.segment                    if segment.answer:                        document_context_list.append(                            DocumentContext(                                content=f"question:{segment.get_sign_content()} answer:{segment.answer}",                                score=record.score,                            )                        )                    else:                        document_context_list.append(                            DocumentContext(                                content=segment.get_sign_content(),                                score=record.score,                            )                        )                if show_retrieve_source:                    for record in records:                        segment = record.segment                        dataset = Dataset.query.filter_by(id=segment.dataset_id).first()                        document = DatasetDocument.query.filter(                            DatasetDocument.id == segment.document_id,                            DatasetDocument.enabled == True,                            DatasetDocument.archived == False,                        ).first()                        if dataset and document:                            source = {                                "dataset_id": dataset.id,                                "dataset_name": dataset.name,                                "document_id": document.id,                                "document_name": document.name,                                "data_source_type": document.data_source_type,                                "segment_id": segment.id,                                "retriever_from": invoke_from.to_source(),                                "score": record.score or 0.0,                            }                            if invoke_from.to_source() == "dev":                                source["hit_count"] = segment.hit_count                                source["word_count"] = segment.word_count                                source["segment_position"] = segment.position                                source["index_node_hash"] = segment.index_node_hash                            if segment.answer:                                source["content"] = f"question:{segment.content} \nanswer:{segment.answer}"                            else:                                source["content"] = segment.content                            retrieval_resource_list.append(source)        if hit_callback and retrieval_resource_list:            retrieval_resource_list = sorted(retrieval_resource_list, key=lambda x: x.get("score") or 0.0, reverse=True)            for position, item in enumerate(retrieval_resource_list, start=1):                item["position"] = position            hit_callback.return_retriever_resource_info(retrieval_resource_list)        if document_context_list:            document_context_list = sorted(document_context_list, key=lambda x: x.score or 0.0, reverse=True)            return str("\n".join([document_context.content for document_context in document_context_list]))        return ""    def single_retrieve(        self,        app_id: str,        tenant_id: str,        user_id: str,        user_from: str,        available_datasets: list,        query: str,        model_instance: ModelInstance,        model_config: ModelConfigWithCredentialsEntity,        planning_strategy: PlanningStrategy,        message_id: Optional[str] = None,    ):        tools = []        for dataset in available_datasets:            description = dataset.description            if not description:                description = "useful for when you want to answer queries about the " + dataset.name            description = description.replace("\n", "").replace("\r", "")            message_tool = PromptMessageTool(                name=dataset.id,                description=description,                parameters={                    "type": "object",                    "properties": {},                    "required": [],                },            )            tools.append(message_tool)        dataset_id = None        if planning_strategy == PlanningStrategy.REACT_ROUTER:            react_multi_dataset_router = ReactMultiDatasetRouter()            dataset_id = react_multi_dataset_router.invoke(                query, tools, model_config, model_instance, user_id, tenant_id            )        elif planning_strategy == PlanningStrategy.ROUTER:            function_call_router = FunctionCallMultiDatasetRouter()            dataset_id = function_call_router.invoke(query, tools, model_config, model_instance)        if dataset_id:            # get retrieval model config            dataset = db.session.query(Dataset).filter(Dataset.id == dataset_id).first()            if dataset:                results = []                if dataset.provider == "external":                    external_documents = ExternalDatasetService.fetch_external_knowledge_retrieval(                        tenant_id=dataset.tenant_id,                        dataset_id=dataset_id,                        query=query,                        external_retrieval_parameters=dataset.retrieval_model,                    )                    for external_document in external_documents:                        document = Document(                            page_content=external_document.get("content"),                            metadata=external_document.get("metadata"),                            provider="external",                        )                        if document.metadata is not None:                            document.metadata["score"] = external_document.get("score")                            document.metadata["title"] = external_document.get("title")                            document.metadata["dataset_id"] = dataset_id                            document.metadata["dataset_name"] = dataset.name                        results.append(document)                else:                    retrieval_model_config = dataset.retrieval_model or default_retrieval_model                    # get top k                    top_k = retrieval_model_config["top_k"]                    # get retrieval method                    if dataset.indexing_technique == "economy":                        retrieval_method = "keyword_search"                    else:                        retrieval_method = retrieval_model_config["search_method"]                    # get reranking model                    reranking_model = (                        retrieval_model_config["reranking_model"]                        if retrieval_model_config["reranking_enable"]                        else None                    )                    # get score threshold                    score_threshold = 0.0                    score_threshold_enabled = retrieval_model_config.get("score_threshold_enabled")                    if score_threshold_enabled:                        score_threshold = retrieval_model_config.get("score_threshold", 0.0)                    with measure_time() as timer:                        results = RetrievalService.retrieve(                            retrieval_method=retrieval_method,                            dataset_id=dataset.id,                            query=query,                            top_k=top_k,                            score_threshold=score_threshold,                            reranking_model=reranking_model,                            reranking_mode=retrieval_model_config.get("reranking_mode", "reranking_model"),                            weights=retrieval_model_config.get("weights", None),                        )                self._on_query(query, [dataset_id], app_id, user_from, user_id)                if results:                    self._on_retrieval_end(results, message_id, timer)                return results        return []    def multiple_retrieve(        self,        app_id: str,        tenant_id: str,        user_id: str,        user_from: str,        available_datasets: list,        query: str,        top_k: int,        score_threshold: float,        reranking_mode: str,        reranking_model: Optional[dict] = None,        weights: Optional[dict[str, Any]] = None,        reranking_enable: bool = True,        message_id: Optional[str] = None,    ):        if not available_datasets:            return []        threads = []        all_documents: list[Document] = []        dataset_ids = [dataset.id for dataset in available_datasets]        index_type_check = all(            item.indexing_technique == available_datasets[0].indexing_technique for item in available_datasets        )        if not index_type_check and (not reranking_enable or reranking_mode != RerankMode.RERANKING_MODEL):            raise ValueError(                "The configured knowledge base list have different indexing technique, please set reranking model."            )        index_type = available_datasets[0].indexing_technique        if index_type == "high_quality":            embedding_model_check = all(                item.embedding_model == available_datasets[0].embedding_model for item in available_datasets            )            embedding_model_provider_check = all(                item.embedding_model_provider == available_datasets[0].embedding_model_provider                for item in available_datasets            )            if (                reranking_enable                and reranking_mode == "weighted_score"                and (not embedding_model_check or not embedding_model_provider_check)            ):                raise ValueError(                    "The configured knowledge base list have different embedding model, please set reranking model."                )            if reranking_enable and reranking_mode == RerankMode.WEIGHTED_SCORE:                if weights is not None:                    weights["vector_setting"]["embedding_provider_name"] = available_datasets[                        0                    ].embedding_model_provider                    weights["vector_setting"]["embedding_model_name"] = available_datasets[0].embedding_model        for dataset in available_datasets:            index_type = dataset.indexing_technique            retrieval_thread = threading.Thread(                target=self._retriever,                kwargs={                    "flask_app": current_app._get_current_object(),  # type: ignore                    "dataset_id": dataset.id,                    "query": query,                    "top_k": top_k,                    "all_documents": all_documents,                },            )            threads.append(retrieval_thread)            retrieval_thread.start()        for thread in threads:            thread.join()        with measure_time() as timer:            if reranking_enable:                # do rerank for searched documents                data_post_processor = DataPostProcessor(tenant_id, reranking_mode, reranking_model, weights, False)                all_documents = data_post_processor.invoke(                    query=query, documents=all_documents, score_threshold=score_threshold, top_n=top_k                )            else:                if index_type == "economy":                    all_documents = self.calculate_keyword_score(query, all_documents, top_k)                elif index_type == "high_quality":                    all_documents = self.calculate_vector_score(all_documents, top_k, score_threshold)        self._on_query(query, dataset_ids, app_id, user_from, user_id)        if all_documents:            self._on_retrieval_end(all_documents, message_id, timer)        return all_documents    def _on_retrieval_end(        self, documents: list[Document], message_id: Optional[str] = None, timer: Optional[dict] = None    ) -> None:        """Handle retrieval end."""        dify_documents = [document for document in documents if document.provider == "dify"]        for document in dify_documents:            if document.metadata is not None:                query = db.session.query(DocumentSegment).filter(                    DocumentSegment.index_node_id == document.metadata["doc_id"]                )                # if 'dataset_id' in document.metadata:                if "dataset_id" in document.metadata:                    query = query.filter(DocumentSegment.dataset_id == document.metadata["dataset_id"])                # add hit count to document segment                query.update({DocumentSegment.hit_count: DocumentSegment.hit_count + 1}, synchronize_session=False)                db.session.commit()        # get tracing instance        trace_manager: TraceQueueManager | None = (            self.application_generate_entity.trace_manager if self.application_generate_entity else None        )        if trace_manager:            trace_manager.add_trace_task(                TraceTask(                    TraceTaskName.DATASET_RETRIEVAL_TRACE, message_id=message_id, documents=documents, timer=timer                )            )    def _on_query(self, query: str, dataset_ids: list[str], app_id: str, user_from: str, user_id: str) -> None:        """        Handle query.        """        if not query:            return        dataset_queries = []        for dataset_id in dataset_ids:            dataset_query = DatasetQuery(                dataset_id=dataset_id,                content=query,                source="app",                source_app_id=app_id,                created_by_role=user_from,                created_by=user_id,            )            dataset_queries.append(dataset_query)        if dataset_queries:            db.session.add_all(dataset_queries)        db.session.commit()    def _retriever(self, flask_app: Flask, dataset_id: str, query: str, top_k: int, all_documents: list):        with flask_app.app_context():            dataset = db.session.query(Dataset).filter(Dataset.id == dataset_id).first()            if not dataset:                return []            if dataset.provider == "external":                external_documents = ExternalDatasetService.fetch_external_knowledge_retrieval(                    tenant_id=dataset.tenant_id,                    dataset_id=dataset_id,                    query=query,                    external_retrieval_parameters=dataset.retrieval_model,                )                for external_document in external_documents:                    document = Document(                        page_content=external_document.get("content"),                        metadata=external_document.get("metadata"),                        provider="external",                    )                    if document.metadata is not None:                        document.metadata["score"] = external_document.get("score")                        document.metadata["title"] = external_document.get("title")                        document.metadata["dataset_id"] = dataset_id                        document.metadata["dataset_name"] = dataset.name                    all_documents.append(document)            else:                # get retrieval model , if the model is not setting , using default                retrieval_model = dataset.retrieval_model or default_retrieval_model                if dataset.indexing_technique == "economy":                    # use keyword table query                    documents = RetrievalService.retrieve(                        retrieval_method="keyword_search", dataset_id=dataset.id, query=query, top_k=top_k                    )                    if documents:                        all_documents.extend(documents)                else:                    if top_k > 0:                        # retrieval source                        documents = RetrievalService.retrieve(                            retrieval_method=retrieval_model["search_method"],                            dataset_id=dataset.id,                            query=query,                            top_k=retrieval_model.get("top_k") or 2,                            score_threshold=retrieval_model.get("score_threshold", 0.0)                            if retrieval_model["score_threshold_enabled"]                            else 0.0,                            reranking_model=retrieval_model.get("reranking_model", None)                            if retrieval_model["reranking_enable"]                            else None,                            reranking_mode=retrieval_model.get("reranking_mode") or "reranking_model",                            weights=retrieval_model.get("weights", None),                        )                        all_documents.extend(documents)    def to_dataset_retriever_tool(        self,        tenant_id: str,        dataset_ids: list[str],        retrieve_config: DatasetRetrieveConfigEntity,        return_resource: bool,        invoke_from: InvokeFrom,        hit_callback: DatasetIndexToolCallbackHandler,    ) -> Optional[list[DatasetRetrieverBaseTool]]:        """        A dataset tool is a tool that can be used to retrieve information from a dataset        :param tenant_id: tenant id        :param dataset_ids: dataset ids        :param retrieve_config: retrieve config        :param return_resource: return resource        :param invoke_from: invoke from        :param hit_callback: hit callback        """        tools = []        available_datasets = []        for dataset_id in dataset_ids:            # get dataset from dataset id            dataset = db.session.query(Dataset).filter(Dataset.tenant_id == tenant_id, Dataset.id == dataset_id).first()            # pass if dataset is not available            if not dataset:                continue            # pass if dataset is not available            if dataset and dataset.provider != "external" and dataset.available_document_count == 0:                continue            available_datasets.append(dataset)        if retrieve_config.retrieve_strategy == DatasetRetrieveConfigEntity.RetrieveStrategy.SINGLE:            # get retrieval model config            default_retrieval_model = {                "search_method": RetrievalMethod.SEMANTIC_SEARCH.value,                "reranking_enable": False,                "reranking_model": {"reranking_provider_name": "", "reranking_model_name": ""},                "top_k": 2,                "score_threshold_enabled": False,            }            for dataset in available_datasets:                retrieval_model_config = dataset.retrieval_model or default_retrieval_model                # get top k                top_k = retrieval_model_config["top_k"]                # get score threshold                score_threshold = None                score_threshold_enabled = retrieval_model_config.get("score_threshold_enabled")                if score_threshold_enabled:                    score_threshold = retrieval_model_config.get("score_threshold")                from core.tools.utils.dataset_retriever.dataset_retriever_tool import DatasetRetrieverTool                tool = DatasetRetrieverTool.from_dataset(                    dataset=dataset,                    top_k=top_k,                    score_threshold=score_threshold,                    hit_callbacks=[hit_callback],                    return_resource=return_resource,                    retriever_from=invoke_from.to_source(),                )                tools.append(tool)        elif retrieve_config.retrieve_strategy == DatasetRetrieveConfigEntity.RetrieveStrategy.MULTIPLE:            from core.tools.utils.dataset_retriever.dataset_multi_retriever_tool import DatasetMultiRetrieverTool            if retrieve_config.reranking_model is None:                raise ValueError("Reranking model is required for multiple retrieval")            tool = DatasetMultiRetrieverTool.from_dataset(                dataset_ids=[dataset.id for dataset in available_datasets],                tenant_id=tenant_id,                top_k=retrieve_config.top_k or 2,                score_threshold=retrieve_config.score_threshold,                hit_callbacks=[hit_callback],                return_resource=return_resource,                retriever_from=invoke_from.to_source(),                reranking_provider_name=retrieve_config.reranking_model.get("reranking_provider_name"),                reranking_model_name=retrieve_config.reranking_model.get("reranking_model_name"),            )            tools.append(tool)        return tools    def calculate_keyword_score(self, query: str, documents: list[Document], top_k: int) -> list[Document]:        """        Calculate keywords scores        :param query: search query        :param documents: documents for reranking        :return:        """        keyword_table_handler = JiebaKeywordTableHandler()        query_keywords = keyword_table_handler.extract_keywords(query, None)        documents_keywords = []        for document in documents:            if document.metadata is not None:                # get the document keywords                document_keywords = keyword_table_handler.extract_keywords(document.page_content, None)                document.metadata["keywords"] = document_keywords                documents_keywords.append(document_keywords)        # Counter query keywords(TF)        query_keyword_counts = Counter(query_keywords)        # total documents        total_documents = len(documents)        # calculate all documents' keywords IDF        all_keywords = set()        for document_keywords in documents_keywords:            all_keywords.update(document_keywords)        keyword_idf = {}        for keyword in all_keywords:            # calculate include query keywords' documents            doc_count_containing_keyword = sum(1 for doc_keywords in documents_keywords if keyword in doc_keywords)            # IDF            keyword_idf[keyword] = math.log((1 + total_documents) / (1 + doc_count_containing_keyword)) + 1        query_tfidf = {}        for keyword, count in query_keyword_counts.items():            tf = count            idf = keyword_idf.get(keyword, 0)            query_tfidf[keyword] = tf * idf        # calculate all documents' TF-IDF        documents_tfidf = []        for document_keywords in documents_keywords:            document_keyword_counts = Counter(document_keywords)            document_tfidf = {}            for keyword, count in document_keyword_counts.items():                tf = count                idf = keyword_idf.get(keyword, 0)                document_tfidf[keyword] = tf * idf            documents_tfidf.append(document_tfidf)        def cosine_similarity(vec1, vec2):            intersection = set(vec1.keys()) & set(vec2.keys())            numerator = sum(vec1[x] * vec2[x] for x in intersection)            sum1 = sum(vec1[x] ** 2 for x in vec1)            sum2 = sum(vec2[x] ** 2 for x in vec2)            denominator = math.sqrt(sum1) * math.sqrt(sum2)            if not denominator:                return 0.0            else:                return float(numerator) / denominator        similarities = []        for document_tfidf in documents_tfidf:            similarity = cosine_similarity(query_tfidf, document_tfidf)            similarities.append(similarity)        for document, score in zip(documents, similarities):            # format document            if document.metadata is not None:                document.metadata["score"] = score        documents = sorted(documents, key=lambda x: x.metadata.get("score", 0) if x.metadata else 0, reverse=True)        return documents[:top_k] if top_k else documents    def calculate_vector_score(        self, all_documents: list[Document], top_k: int, score_threshold: float    ) -> list[Document]:        filter_documents = []        for document in all_documents:            if score_threshold is None or (document.metadata and document.metadata.get("score", 0) >= score_threshold):                filter_documents.append(document)        if not filter_documents:            return []        filter_documents = sorted(            filter_documents, key=lambda x: x.metadata.get("score", 0) if x.metadata else 0, reverse=True        )        return filter_documents[:top_k] if top_k else filter_documents
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