feat(api): implement conversation variable reset api.

api/controllers/console/app/workflow_draft_variable.py

@@ -245,6 +245,41 @@ class VariableApi(Resource):
         return Response("", 204)
 
 
+class VariableResetApi(Resource):
+    @_api_prerequisite
+    @marshal_with(_WORKFLOW_DRAFT_VARIABLE_FIELDS)
+    def put(self, app_model: App, variable_id: str):
+        draft_var_srv = WorkflowDraftVariableService(
+            session=db.session(),
+        )
+
+        workflow_srv = WorkflowService()
+        draft_workflow = workflow_srv.get_draft_workflow(app_model)
+        if draft_workflow is None:
+            raise NotFoundError(
+                f"Draft workflow not found, app_id={app_model.id}",
+            )
+        variable = draft_var_srv.get_variable(variable_id=variable_id)
+        if variable is None:
+            raise NotFoundError(description=f"variable not found, id={variable_id}")
+        if variable.app_id != app_model.id:
+            raise NotFoundError(description=f"variable not found, id={variable_id}")
+
+        if variable.node_id != CONVERSATION_VARIABLE_NODE_ID:
+            error_msg = "variable is not a conversation variable, id={}, node_id={},  name={}".format(
+                variable.id,
+                variable.node_id,
+                variable.name,
+            )
+            raise InvalidArgumentError(error_msg)
+        resetted = draft_var_srv.reset_conversation_variable(draft_workflow, variable)
+        db.session.commit()
+        if resetted is None:
+            return Response("", 204)
+        else:
+            return variable
+
+
 def _get_variable_list(app_model: App, node_id) -> WorkflowDraftVariableList:
     with Session(bind=db.engine, expire_on_commit=False) as session:
         draft_var_srv = WorkflowDraftVariableService(
@@ -321,6 +356,7 @@ api.add_resource(
 )
 api.add_resource(NodeVariableCollectionApi, "/apps/<uuid:app_id>/workflows/draft/nodes/<string:node_id>/variables")
 api.add_resource(VariableApi, "/apps/<uuid:app_id>/workflows/draft/variables/<uuid:variable_id>")
+api.add_resource(VariableApi, "/apps/<uuid:app_id>/workflows/draft/variables/<uuid:variable_id>/reset")
 
 api.add_resource(ConversationVariableCollectionApi, "/apps/<uuid:app_id>/workflows/draft/conversation-variables")
 api.add_resource(SystemVariableCollectionApi, "/apps/<uuid:app_id>/workflows/draft/system-variables")

api/core/file/constants.py

@@ -1 +1,5 @@
+# TODO(QuantumGhost): Refactor variable type identification. Instead of directly
+# comparing `dify_model_identity` with constants throughout the codebase, extract
+# this logic into a dedicated function. This would encapsulate the implementation
+# details of how different variable types are identified.
 FILE_MODEL_IDENTITY = "__dify__file__"

api/services/workflow_draft_variable_service.py

@@ -32,6 +32,10 @@ class WorkflowDraftVariableList:
     total: int | None = None
 
 
+class _DraftVarServiceError(Exception):
+    pass
+
+
 class DraftVarLoader(VariableLoader):
     # This implements the VariableLoader interface for loading draft variables.
     #
@@ -200,6 +204,25 @@ class WorkflowDraftVariableService:
         self._session.flush()
         return variable
 
+    def reset_conversation_variable(
+        self, workflow: Workflow, variable: WorkflowDraftVariable
+    ) -> WorkflowDraftVariable | None:
+        conv_var_by_name = {i.name: i for i in workflow.conversation_variables}
+        conv_var = conv_var_by_name.get(variable.name)
+
+        if conv_var is None:
+            self._session.delete(instance=variable)
+            self._session.flush()
+            _logger.warning(
+                "Conversation variable not found for draft variable, id=%s, name=%s", variable.id, variable.name
+            )
+            return None
+
+        variable.set_value(conv_var)
+        self._session.add(variable)
+        self._session.flush()
+        return variable
+
     def delete_variable(self, variable: WorkflowDraftVariable):
         self._session.delete(variable)
 

api/services/workflow_service.py

@@ -1,5 +1,4 @@
 import json
-import logging
 import time
 import uuid
 from collections.abc import Callable, Generator, Mapping, Sequence
@@ -32,7 +31,6 @@ from core.workflow.workflow_entry import WorkflowEntry
 from events.app_event import app_draft_workflow_was_synced, app_published_workflow_was_updated
 from extensions.ext_database import db
 from factories.variable_factory import segment_to_variable
-from libs import gen_utils
 from models.account import Account
 from models.model import App, AppMode
 from models.tools import WorkflowToolProvider