fix: allow persist Flow state with BaseModel entries (#3276)

Co-authored-by: Lorenze Jay <63378463+lorenzejay@users.noreply.github.com>

src/crewai/flow/persistence/sqlite.py

@@ -81,7 +81,7 @@ class SQLiteFlowPersistence(FlowPersistence):
         """
         # Convert state_data to dict, handling both Pydantic and dict cases
         if isinstance(state_data, BaseModel):
-            state_dict = dict(state_data)  # Use dict() for better type compatibility
+            state_dict = state_data.model_dump()
         elif isinstance(state_data, dict):
             state_dict = state_data
         else:

tests/test_flow_persistence.py

@@ -1,9 +1,8 @@
 """Test flow state persistence functionality."""
 
 import os
-from typing import Dict
+from typing import Dict, List
 
-import pytest
 from pydantic import BaseModel
 
 from crewai.flow.flow import Flow, FlowState, listen, start
@@ -208,3 +207,44 @@ def test_persist_decorator_verbose_logging(tmp_path, caplog):
     flow = VerboseFlow(persistence=persistence)
     flow.kickoff()
     assert "Saving flow state" in caplog.text
+
+
+
+def test_persistence_with_base_model(tmp_path):
+    db_path = os.path.join(tmp_path, "test_flows.db")
+    persistence = SQLiteFlowPersistence(db_path)
+
+    class Message(BaseModel):
+        role: str
+        type: str
+        content: str
+
+    class State(FlowState):
+        latest_message: Message | None = None
+        history: List[Message] = []
+
+    @persist(persistence)
+    class BaseModelFlow(Flow[State]):
+        initial_state = State(latest_message=None, history=[])
+
+        @start()
+        def init_step(self):
+            self.state.latest_message = Message(role="user", type="text", content="Hello, World!")
+            self.state.history.append(self.state.latest_message)
+
+    flow = BaseModelFlow(persistence=persistence)
+    flow.kickoff()
+
+    latest_message = flow.state.latest_message
+    message, = flow.state.history
+
+    assert latest_message is not None
+    assert latest_message.role == "user"
+    assert latest_message.type == "text"
+    assert latest_message.content == "Hello, World!"
+
+    assert len(flow.state.history) == 1
+    assert message.role == "user"
+    assert message.type == "text"
+    assert message.content == "Hello, World!"
+    assert isinstance(flow.state, State)