Feat: Add metadata filtering function for /api/v1/retrieval (#9877)

-Added the metadata_dedition parameter in the document retrieval
interface to filter document metadata -Updated the API documentation and
added explanations for the metadata_dedition parameter

### What problem does this PR solve?

Make /api/v1/retrieval api also can use metadata filter

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

api/apps/sdk/doc.py

@@ -35,6 +35,8 @@ from api.db.services.knowledgebase_service import KnowledgebaseService
 from api.db.services.llm_service import LLMBundle
 from api.db.services.tenant_llm_service import TenantLLMService
 from api.db.services.task_service import TaskService, queue_tasks
+from api.db.services.dialog_service import meta_filter
+from api.apps.sdk.dify_retrieval import convert_conditions
 from api.utils.api_utils import check_duplicate_ids, construct_json_result, get_error_data_result, get_parser_config, get_result, server_error_response, token_required
 from rag.app.qa import beAdoc, rmPrefix
 from rag.app.tag import label_question
@@ -1350,6 +1352,9 @@ def retrieval_test(tenant_id):
             highlight:
               type: boolean
               description: Whether to highlight matched content.
+            metadata_condition:
+              type: object
+              description: metadata filter condition.
       - in: header
         name: Authorization
         type: string
@@ -1413,6 +1418,10 @@ def retrieval_test(tenant_id):
     for doc_id in doc_ids:
         if doc_id not in doc_ids_list:
             return get_error_data_result(f"The datasets don't own the document {doc_id}")
+    if not doc_ids:
+        metadata_condition = req.get("metadata_condition", {})
+        metas = DocumentService.get_meta_by_kbs(kb_ids)
+        doc_ids = meta_filter(metas, convert_conditions(metadata_condition))
     similarity_threshold = float(req.get("similarity_threshold", 0.2))
     vector_similarity_weight = float(req.get("vector_similarity_weight", 0.3))
     top = int(req.get("top_k", 1024))