Refactor event base classes (#2491)

- Renamed `CrewEvent` to `BaseEvent` across the codebase for consistency
- Created a `CrewBaseEvent` that automatically identifies fingerprints for DRY
- Added a new `to_json()` method for serializing events

docs/concepts/event-listener.mdx

@@ -13,7 +13,7 @@ CrewAI provides a powerful event system that allows you to listen for and react
 CrewAI uses an event bus architecture to emit events throughout the execution lifecycle. The event system is built on the following components:
 
 1. **CrewAIEventsBus**: A singleton event bus that manages event registration and emission
-2. **CrewEvent**: Base class for all events in the system
+2. **BaseEvent**: Base class for all events in the system
 3. **BaseEventListener**: Abstract base class for creating custom event listeners
 
 When specific actions occur in CrewAI (like a Crew starting execution, an Agent completing a task, or a tool being used), the system emits corresponding events. You can register handlers for these events to execute custom code when they occur.
@@ -234,7 +234,7 @@ Each event handler receives two parameters:
 1. **source**: The object that emitted the event
 2. **event**: The event instance, containing event-specific data
 
-The structure of the event object depends on the event type, but all events inherit from `CrewEvent` and include:
+The structure of the event object depends on the event type, but all events inherit from `BaseEvent` and include:
 
 - **timestamp**: The time when the event was emitted
 - **type**: A string identifier for the event type

src/crewai/utilities/events/agent_events.py

@@ -4,13 +4,13 @@ from crewai.agents.agent_builder.base_agent import BaseAgent
 from crewai.tools.base_tool import BaseTool
 from crewai.tools.structured_tool import CrewStructuredTool
 
-from .base_events import CrewEvent
+from .base_events import BaseEvent
 
 if TYPE_CHECKING:
     from crewai.agents.agent_builder.base_agent import BaseAgent
 
 
-class AgentExecutionStartedEvent(CrewEvent):
+class AgentExecutionStartedEvent(BaseEvent):
     """Event emitted when an agent starts executing a task"""
 
     agent: BaseAgent
@@ -24,14 +24,17 @@ class AgentExecutionStartedEvent(CrewEvent):
     def __init__(self, **data):
         super().__init__(**data)
         # Set fingerprint data from the agent
-        if hasattr(self.agent, 'fingerprint') and self.agent.fingerprint:
+        if hasattr(self.agent, "fingerprint") and self.agent.fingerprint:
             self.source_fingerprint = self.agent.fingerprint.uuid_str
             self.source_type = "agent"
-            if hasattr(self.agent.fingerprint, 'metadata') and self.agent.fingerprint.metadata:
+            if (
+                hasattr(self.agent.fingerprint, "metadata")
+                and self.agent.fingerprint.metadata
+            ):
                 self.fingerprint_metadata = self.agent.fingerprint.metadata
 
 
-class AgentExecutionCompletedEvent(CrewEvent):
+class AgentExecutionCompletedEvent(BaseEvent):
     """Event emitted when an agent completes executing a task"""
 
     agent: BaseAgent
@@ -42,14 +45,17 @@ class AgentExecutionCompletedEvent(CrewEvent):
     def __init__(self, **data):
         super().__init__(**data)
         # Set fingerprint data from the agent
-        if hasattr(self.agent, 'fingerprint') and self.agent.fingerprint:
+        if hasattr(self.agent, "fingerprint") and self.agent.fingerprint:
             self.source_fingerprint = self.agent.fingerprint.uuid_str
             self.source_type = "agent"
-            if hasattr(self.agent.fingerprint, 'metadata') and self.agent.fingerprint.metadata:
+            if (
+                hasattr(self.agent.fingerprint, "metadata")
+                and self.agent.fingerprint.metadata
+            ):
                 self.fingerprint_metadata = self.agent.fingerprint.metadata
 
 
-class AgentExecutionErrorEvent(CrewEvent):
+class AgentExecutionErrorEvent(BaseEvent):
     """Event emitted when an agent encounters an error during execution"""
 
     agent: BaseAgent
@@ -60,8 +66,11 @@ class AgentExecutionErrorEvent(CrewEvent):
     def __init__(self, **data):
         super().__init__(**data)
         # Set fingerprint data from the agent
-        if hasattr(self.agent, 'fingerprint') and self.agent.fingerprint:
+        if hasattr(self.agent, "fingerprint") and self.agent.fingerprint:
             self.source_fingerprint = self.agent.fingerprint.uuid_str
             self.source_type = "agent"
-            if hasattr(self.agent.fingerprint, 'metadata') and self.agent.fingerprint.metadata:
+            if (
+                hasattr(self.agent.fingerprint, "metadata")
+                and self.agent.fingerprint.metadata
+            ):
                 self.fingerprint_metadata = self.agent.fingerprint.metadata

src/crewai/utilities/events/base_events.py

@@ -3,12 +3,26 @@ from typing import Any, Dict, Optional
 
 from pydantic import BaseModel, Field
 
+from crewai.utilities.serialization import to_serializable
 
-class CrewEvent(BaseModel):
-    """Base class for all crew events"""
+
+class BaseEvent(BaseModel):
+    """Base class for all events"""
 
     timestamp: datetime = Field(default_factory=datetime.now)
     type: str
     source_fingerprint: Optional[str] = None  # UUID string of the source entity
     source_type: Optional[str] = None  # "agent", "task", "crew"
     fingerprint_metadata: Optional[Dict[str, Any]] = None  # Any relevant metadata
+
+    def to_json(self, exclude: set[str] | None = None):
+        """
+        Converts the event to a JSON-serializable dictionary.
+
+        Args:
+            exclude (set[str], optional): Set of keys to exclude from the result. Defaults to None.
+
+        Returns:
+            dict: A JSON-serializable dictionary.
+        """
+        return to_serializable(self, exclude=exclude)

src/crewai/utilities/events/crew_events.py

@@ -1,171 +1,102 @@
-from typing import Any, Dict, Optional, Union
+from typing import TYPE_CHECKING, Any, Dict, Optional, Union
 
-from pydantic import InstanceOf
+from crewai.utilities.events.base_events import BaseEvent
 
-from crewai.utilities.events.base_events import CrewEvent
+if TYPE_CHECKING:
+    from crewai.crew import Crew
+else:
+    Crew = Any
 
 
-class CrewKickoffStartedEvent(CrewEvent):
+class CrewBaseEvent(BaseEvent):
+    """Base class for crew events with fingerprint handling"""
+
+    crew_name: Optional[str]
+    crew: Optional[Crew] = None
+
+    def __init__(self, **data):
+        super().__init__(**data)
+        self.set_crew_fingerprint()
+
+    def set_crew_fingerprint(self) -> None:
+        if self.crew and hasattr(self.crew, "fingerprint") and self.crew.fingerprint:
+            self.source_fingerprint = self.crew.fingerprint.uuid_str
+            self.source_type = "crew"
+            if (
+                hasattr(self.crew.fingerprint, "metadata")
+                and self.crew.fingerprint.metadata
+            ):
+                self.fingerprint_metadata = self.crew.fingerprint.metadata
+
+    def to_json(self, exclude: set[str] | None = None):
+        if exclude is None:
+            exclude = set()
+        exclude.add("crew")
+        return super().to_json(exclude=exclude)
+
+
+class CrewKickoffStartedEvent(CrewBaseEvent):
     """Event emitted when a crew starts execution"""
 
-    crew_name: Optional[str]
     inputs: Optional[Dict[str, Any]]
     type: str = "crew_kickoff_started"
-    crew: Optional[Any] = None
-
-    def __init__(self, **data):
-        super().__init__(**data)
-        # Set fingerprint data from the crew
-        if self.crew and hasattr(self.crew, 'fingerprint') and self.crew.fingerprint:
-            self.source_fingerprint = self.crew.fingerprint.uuid_str
-            self.source_type = "crew"
-            if hasattr(self.crew.fingerprint, 'metadata') and self.crew.fingerprint.metadata:
-                self.fingerprint_metadata = self.crew.fingerprint.metadata
 
 
-class CrewKickoffCompletedEvent(CrewEvent):
+class CrewKickoffCompletedEvent(CrewBaseEvent):
     """Event emitted when a crew completes execution"""
 
-    crew_name: Optional[str]
     output: Any
     type: str = "crew_kickoff_completed"
-    crew: Optional[Any] = None
-
-    def __init__(self, **data):
-        super().__init__(**data)
-        # Set fingerprint data from the crew
-        if self.crew and hasattr(self.crew, 'fingerprint') and self.crew.fingerprint:
-            self.source_fingerprint = self.crew.fingerprint.uuid_str
-            self.source_type = "crew"
-            if hasattr(self.crew.fingerprint, 'metadata') and self.crew.fingerprint.metadata:
-                self.fingerprint_metadata = self.crew.fingerprint.metadata
 
 
-class CrewKickoffFailedEvent(CrewEvent):
+class CrewKickoffFailedEvent(CrewBaseEvent):
     """Event emitted when a crew fails to complete execution"""
 
     error: str
-    crew_name: Optional[str]
     type: str = "crew_kickoff_failed"
-    crew: Optional[Any] = None
-
-    def __init__(self, **data):
-        super().__init__(**data)
-        # Set fingerprint data from the crew
-        if self.crew and hasattr(self.crew, 'fingerprint') and self.crew.fingerprint:
-            self.source_fingerprint = self.crew.fingerprint.uuid_str
-            self.source_type = "crew"
-            if hasattr(self.crew.fingerprint, 'metadata') and self.crew.fingerprint.metadata:
-                self.fingerprint_metadata = self.crew.fingerprint.metadata
 
 
-class CrewTrainStartedEvent(CrewEvent):
+class CrewTrainStartedEvent(CrewBaseEvent):
     """Event emitted when a crew starts training"""
 
-    crew_name: Optional[str]
     n_iterations: int
     filename: str
     inputs: Optional[Dict[str, Any]]
     type: str = "crew_train_started"
-    crew: Optional[Any] = None
-
-    def __init__(self, **data):
-        super().__init__(**data)
-        # Set fingerprint data from the crew
-        if self.crew and hasattr(self.crew, 'fingerprint') and self.crew.fingerprint:
-            self.source_fingerprint = self.crew.fingerprint.uuid_str
-            self.source_type = "crew"
-            if hasattr(self.crew.fingerprint, 'metadata') and self.crew.fingerprint.metadata:
-                self.fingerprint_metadata = self.crew.fingerprint.metadata
 
 
-class CrewTrainCompletedEvent(CrewEvent):
+class CrewTrainCompletedEvent(CrewBaseEvent):
     """Event emitted when a crew completes training"""
 
-    crew_name: Optional[str]
     n_iterations: int
     filename: str
     type: str = "crew_train_completed"
-    crew: Optional[Any] = None
-
-    def __init__(self, **data):
-        super().__init__(**data)
-        # Set fingerprint data from the crew
-        if self.crew and hasattr(self.crew, 'fingerprint') and self.crew.fingerprint:
-            self.source_fingerprint = self.crew.fingerprint.uuid_str
-            self.source_type = "crew"
-            if hasattr(self.crew.fingerprint, 'metadata') and self.crew.fingerprint.metadata:
-                self.fingerprint_metadata = self.crew.fingerprint.metadata
 
 
-class CrewTrainFailedEvent(CrewEvent):
+class CrewTrainFailedEvent(CrewBaseEvent):
     """Event emitted when a crew fails to complete training"""
 
     error: str
-    crew_name: Optional[str]
     type: str = "crew_train_failed"
-    crew: Optional[Any] = None
-
-    def __init__(self, **data):
-        super().__init__(**data)
-        # Set fingerprint data from the crew
-        if self.crew and hasattr(self.crew, 'fingerprint') and self.crew.fingerprint:
-            self.source_fingerprint = self.crew.fingerprint.uuid_str
-            self.source_type = "crew"
-            if hasattr(self.crew.fingerprint, 'metadata') and self.crew.fingerprint.metadata:
-                self.fingerprint_metadata = self.crew.fingerprint.metadata
 
 
-class CrewTestStartedEvent(CrewEvent):
+class CrewTestStartedEvent(CrewBaseEvent):
     """Event emitted when a crew starts testing"""
 
-    crew_name: Optional[str]
     n_iterations: int
     eval_llm: Optional[Union[str, Any]]
     inputs: Optional[Dict[str, Any]]
     type: str = "crew_test_started"
-    crew: Optional[Any] = None
-
-    def __init__(self, **data):
-        super().__init__(**data)
-        # Set fingerprint data from the crew
-        if self.crew and hasattr(self.crew, 'fingerprint') and self.crew.fingerprint:
-            self.source_fingerprint = self.crew.fingerprint.uuid_str
-            self.source_type = "crew"
-            if hasattr(self.crew.fingerprint, 'metadata') and self.crew.fingerprint.metadata:
-                self.fingerprint_metadata = self.crew.fingerprint.metadata
 
 
-class CrewTestCompletedEvent(CrewEvent):
+class CrewTestCompletedEvent(CrewBaseEvent):
     """Event emitted when a crew completes testing"""
 
-    crew_name: Optional[str]
     type: str = "crew_test_completed"
-    crew: Optional[Any] = None
-
-    def __init__(self, **data):
-        super().__init__(**data)
-        # Set fingerprint data from the crew
-        if self.crew and hasattr(self.crew, 'fingerprint') and self.crew.fingerprint:
-            self.source_fingerprint = self.crew.fingerprint.uuid_str
-            self.source_type = "crew"
-            if hasattr(self.crew.fingerprint, 'metadata') and self.crew.fingerprint.metadata:
-                self.fingerprint_metadata = self.crew.fingerprint.metadata
 
 
-class CrewTestFailedEvent(CrewEvent):
+class CrewTestFailedEvent(CrewBaseEvent):
     """Event emitted when a crew fails to complete testing"""
 
     error: str
-    crew_name: Optional[str]
     type: str = "crew_test_failed"
-    crew: Optional[Any] = None
-
-    def __init__(self, **data):
-        super().__init__(**data)
-        # Set fingerprint data from the crew
-        if self.crew and hasattr(self.crew, 'fingerprint') and self.crew.fingerprint:
-            self.source_fingerprint = self.crew.fingerprint.uuid_str
-            self.source_type = "crew"
-            if hasattr(self.crew.fingerprint, 'metadata') and self.crew.fingerprint.metadata:
-                self.fingerprint_metadata = self.crew.fingerprint.metadata

src/crewai/utilities/events/crewai_event_bus.py

@@ -4,10 +4,10 @@ from typing import Any, Callable, Dict, List, Type, TypeVar, cast
 
 from blinker import Signal
 
-from crewai.utilities.events.base_events import CrewEvent
+from crewai.utilities.events.base_events import BaseEvent
 from crewai.utilities.events.event_types import EventTypes
 
-EventT = TypeVar("EventT", bound=CrewEvent)
+EventT = TypeVar("EventT", bound=BaseEvent)
 
 
 class CrewAIEventsBus:
@@ -30,7 +30,7 @@ class CrewAIEventsBus:
     def _initialize(self) -> None:
         """Initialize the event bus internal state"""
         self._signal = Signal("crewai_event_bus")
-        self._handlers: Dict[Type[CrewEvent], List[Callable]] = {}
+        self._handlers: Dict[Type[BaseEvent], List[Callable]] = {}
 
     def on(
         self, event_type: Type[EventT]
@@ -59,7 +59,7 @@ class CrewAIEventsBus:
 
         return decorator
 
-    def emit(self, source: Any, event: CrewEvent) -> None:
+    def emit(self, source: Any, event: BaseEvent) -> None:
         """
         Emit an event to all registered handlers
 

src/crewai/utilities/events/flow_events.py

@@ -2,10 +2,10 @@ from typing import Any, Dict, Optional, Union
 
 from pydantic import BaseModel, ConfigDict
 
-from .base_events import CrewEvent
+from .base_events import BaseEvent
 
 
-class FlowEvent(CrewEvent):
+class FlowEvent(BaseEvent):
     """Base class for all flow events"""
 
     type: str

src/crewai/utilities/events/llm_events.py

@@ -1,7 +1,7 @@
 from enum import Enum
 from typing import Any, Dict, List, Optional, Union
 
-from crewai.utilities.events.base_events import CrewEvent
+from crewai.utilities.events.base_events import BaseEvent
 
 
 class LLMCallType(Enum):
@@ -11,7 +11,7 @@ class LLMCallType(Enum):
     LLM_CALL = "llm_call"
 
 
-class LLMCallStartedEvent(CrewEvent):
+class LLMCallStartedEvent(BaseEvent):
     """Event emitted when a LLM call starts
 
     Attributes:
@@ -26,7 +26,7 @@ class LLMCallStartedEvent(CrewEvent):
     available_functions: Optional[Dict[str, Any]] = None
 
 
-class LLMCallCompletedEvent(CrewEvent):
+class LLMCallCompletedEvent(BaseEvent):
     """Event emitted when a LLM call completes"""
 
     type: str = "llm_call_completed"
@@ -34,14 +34,14 @@ class LLMCallCompletedEvent(CrewEvent):
     call_type: LLMCallType
 
 
-class LLMCallFailedEvent(CrewEvent):
+class LLMCallFailedEvent(BaseEvent):
     """Event emitted when a LLM call fails"""
 
     error: str
     type: str = "llm_call_failed"
 
 
-class LLMStreamChunkEvent(CrewEvent):
+class LLMStreamChunkEvent(BaseEvent):
     """Event emitted when a streaming chunk is received"""
 
     type: str = "llm_stream_chunk"

src/crewai/utilities/events/task_events.py

@@ -1,10 +1,10 @@
 from typing import Any, Optional
 
 from crewai.tasks.task_output import TaskOutput
-from crewai.utilities.events.base_events import CrewEvent
+from crewai.utilities.events.base_events import BaseEvent
 
 
-class TaskStartedEvent(CrewEvent):
+class TaskStartedEvent(BaseEvent):
     """Event emitted when a task starts"""
 
     type: str = "task_started"
@@ -14,14 +14,17 @@ class TaskStartedEvent(CrewEvent):
     def __init__(self, **data):
         super().__init__(**data)
         # Set fingerprint data from the task
-        if hasattr(self.task, 'fingerprint') and self.task.fingerprint:
+        if hasattr(self.task, "fingerprint") and self.task.fingerprint:
             self.source_fingerprint = self.task.fingerprint.uuid_str
             self.source_type = "task"
-            if hasattr(self.task.fingerprint, 'metadata') and self.task.fingerprint.metadata:
+            if (
+                hasattr(self.task.fingerprint, "metadata")
+                and self.task.fingerprint.metadata
+            ):
                 self.fingerprint_metadata = self.task.fingerprint.metadata
 
 
-class TaskCompletedEvent(CrewEvent):
+class TaskCompletedEvent(BaseEvent):
     """Event emitted when a task completes"""
 
     output: TaskOutput
@@ -31,14 +34,17 @@ class TaskCompletedEvent(CrewEvent):
     def __init__(self, **data):
         super().__init__(**data)
         # Set fingerprint data from the task
-        if hasattr(self.task, 'fingerprint') and self.task.fingerprint:
+        if hasattr(self.task, "fingerprint") and self.task.fingerprint:
             self.source_fingerprint = self.task.fingerprint.uuid_str
             self.source_type = "task"
-            if hasattr(self.task.fingerprint, 'metadata') and self.task.fingerprint.metadata:
+            if (
+                hasattr(self.task.fingerprint, "metadata")
+                and self.task.fingerprint.metadata
+            ):
                 self.fingerprint_metadata = self.task.fingerprint.metadata
 
 
-class TaskFailedEvent(CrewEvent):
+class TaskFailedEvent(BaseEvent):
     """Event emitted when a task fails"""
 
     error: str
@@ -48,14 +54,17 @@ class TaskFailedEvent(CrewEvent):
     def __init__(self, **data):
         super().__init__(**data)
         # Set fingerprint data from the task
-        if hasattr(self.task, 'fingerprint') and self.task.fingerprint:
+        if hasattr(self.task, "fingerprint") and self.task.fingerprint:
             self.source_fingerprint = self.task.fingerprint.uuid_str
             self.source_type = "task"
-            if hasattr(self.task.fingerprint, 'metadata') and self.task.fingerprint.metadata:
+            if (
+                hasattr(self.task.fingerprint, "metadata")
+                and self.task.fingerprint.metadata
+            ):
                 self.fingerprint_metadata = self.task.fingerprint.metadata
 
 
-class TaskEvaluationEvent(CrewEvent):
+class TaskEvaluationEvent(BaseEvent):
     """Event emitted when a task evaluation is completed"""
 
     type: str = "task_evaluation"
@@ -65,8 +74,11 @@ class TaskEvaluationEvent(CrewEvent):
     def __init__(self, **data):
         super().__init__(**data)
         # Set fingerprint data from the task
-        if hasattr(self.task, 'fingerprint') and self.task.fingerprint:
+        if hasattr(self.task, "fingerprint") and self.task.fingerprint:
             self.source_fingerprint = self.task.fingerprint.uuid_str
             self.source_type = "task"
-            if hasattr(self.task.fingerprint, 'metadata') and self.task.fingerprint.metadata:
+            if (
+                hasattr(self.task.fingerprint, "metadata")
+                and self.task.fingerprint.metadata
+            ):
                 self.fingerprint_metadata = self.task.fingerprint.metadata

src/crewai/utilities/events/tool_usage_events.py

@@ -1,10 +1,10 @@
 from datetime import datetime
 from typing import Any, Callable, Dict, Optional
 
-from .base_events import CrewEvent
+from .base_events import BaseEvent
 
 
-class ToolUsageEvent(CrewEvent):
+class ToolUsageEvent(BaseEvent):
     """Base event for tool usage tracking"""
 
     agent_key: str
@@ -21,10 +21,13 @@ class ToolUsageEvent(CrewEvent):
     def __init__(self, **data):
         super().__init__(**data)
         # Set fingerprint data from the agent
-        if self.agent and hasattr(self.agent, 'fingerprint') and self.agent.fingerprint:
+        if self.agent and hasattr(self.agent, "fingerprint") and self.agent.fingerprint:
             self.source_fingerprint = self.agent.fingerprint.uuid_str
             self.source_type = "agent"
-            if hasattr(self.agent.fingerprint, 'metadata') and self.agent.fingerprint.metadata:
+            if (
+                hasattr(self.agent.fingerprint, "metadata")
+                and self.agent.fingerprint.metadata
+            ):
                 self.fingerprint_metadata = self.agent.fingerprint.metadata
 
 
@@ -65,7 +68,7 @@ class ToolSelectionErrorEvent(ToolUsageEvent):
     type: str = "tool_selection_error"
 
 
-class ToolExecutionErrorEvent(CrewEvent):
+class ToolExecutionErrorEvent(BaseEvent):
     """Event emitted when a tool execution encounters an error"""
 
     error: Any
@@ -78,8 +81,11 @@ class ToolExecutionErrorEvent(CrewEvent):
     def __init__(self, **data):
         super().__init__(**data)
         # Set fingerprint data from the agent
-        if self.agent and hasattr(self.agent, 'fingerprint') and self.agent.fingerprint:
+        if self.agent and hasattr(self.agent, "fingerprint") and self.agent.fingerprint:
             self.source_fingerprint = self.agent.fingerprint.uuid_str
             self.source_type = "agent"
-            if hasattr(self.agent.fingerprint, 'metadata') and self.agent.fingerprint.metadata:
+            if (
+                hasattr(self.agent.fingerprint, "metadata")
+                and self.agent.fingerprint.metadata
+            ):
                 self.fingerprint_metadata = self.agent.fingerprint.metadata

src/crewai/utilities/serialization.py

@@ -5,35 +5,17 @@ from typing import Any, Dict, List, Union
 
 from pydantic import BaseModel
 
-from crewai.flow import Flow
-
 SerializablePrimitive = Union[str, int, float, bool, None]
 Serializable = Union[
     SerializablePrimitive, List["Serializable"], Dict[str, "Serializable"]
 ]
 
 
-def export_state(flow: Flow) -> dict[str, Serializable]:
-    """Exports the Flow's internal state as JSON-compatible data structures.
-
-    Performs a one-way transformation of a Flow's state into basic Python types
-    that can be safely serialized to JSON. To prevent infinite recursion with
-    circular references, the conversion is limited to a depth of 5 levels.
-
-    Args:
-        flow: The Flow object whose state needs to be exported
-
-    Returns:
-        dict[str, Any]: The transformed state using JSON-compatible Python
-            types.
-    """
-    result = to_serializable(flow._state)
-    assert isinstance(result, dict)
-    return result
-
-
 def to_serializable(
-    obj: Any, exclude: set[str] | None = None, max_depth: int = 5, _current_depth: int = 0
+    obj: Any,
+    exclude: set[str] | None = None,
+    max_depth: int = 5,
+    _current_depth: int = 0,
 ) -> Serializable:
     """Converts a Python object into a JSON-compatible representation.
 

tests/utilities/events/test_crewai_event_bus.py

@@ -1,10 +1,10 @@
 from unittest.mock import Mock
 
-from crewai.utilities.events.base_events import CrewEvent
+from crewai.utilities.events.base_events import BaseEvent
 from crewai.utilities.events.crewai_event_bus import crewai_event_bus
 
 
-class TestEvent(CrewEvent):
+class TestEvent(BaseEvent):
     pass
 
 
@@ -24,7 +24,7 @@ def test_specific_event_handler():
 def test_wildcard_event_handler():
     mock_handler = Mock()
 
-    @crewai_event_bus.on(CrewEvent)
+    @crewai_event_bus.on(BaseEvent)
     def handler(source, event):
         mock_handler(source, event)
 

tests/utilities/test_serialization.py

@@ -5,8 +5,7 @@ from unittest.mock import Mock
 import pytest
 from pydantic import BaseModel
 
-from crewai.flow import Flow
-from crewai.flow.state_utils import export_state, to_serializable, to_string
+from crewai.utilities.serialization import to_serializable, to_string
 
 
 class Address(BaseModel):
@@ -23,16 +22,6 @@ class Person(BaseModel):
     skills: List[str]
 
 
-@pytest.fixture
-def mock_flow():
-    def create_flow(state):
-        flow = Mock(spec=Flow)
-        flow._state = state
-        return flow
-
-    return create_flow
-
-
 @pytest.mark.parametrize(
     "test_input,expected",
     [
@@ -47,9 +36,8 @@ def mock_flow():
         ({"nested": [1, [2, 3], {4, 5}]}, {"nested": [1, [2, 3], [4, 5]]}),
     ],
 )
-def test_basic_serialization(mock_flow, test_input, expected):
-    flow = mock_flow(test_input)
-    result = export_state(flow)
+def test_basic_serialization(test_input, expected):
+    result = to_serializable(test_input)
     assert result == expected
 
 
@@ -60,9 +48,8 @@ def test_basic_serialization(mock_flow, test_input, expected):
         (datetime(2024, 1, 1, 12, 30), "2024-01-01T12:30:00"),
     ],
 )
-def test_temporal_serialization(mock_flow, input_date, expected):
-    flow = mock_flow({"date": input_date})
-    result = export_state(flow)
+def test_temporal_serialization(input_date, expected):
+    result = to_serializable({"date": input_date})
     assert result["date"] == expected
 
 
@@ -75,9 +62,8 @@ def test_temporal_serialization(mock_flow, input_date, expected):
         ("normal", "value", str),
     ],
 )
-def test_dictionary_key_serialization(mock_flow, key, value, expected_key_type):
-    flow = mock_flow({key: value})
-    result = export_state(flow)
+def test_dictionary_key_serialization(key, value, expected_key_type):
+    result = to_serializable({key: value})
     assert len(result) == 1
     result_key = next(iter(result.keys()))
     assert isinstance(result_key, expected_key_type)
@@ -91,14 +77,13 @@ def test_dictionary_key_serialization(mock_flow, key, value, expected_key_type):
         (str.upper, "upper"),
     ],
 )
-def test_callable_serialization(mock_flow, callable_obj, expected_in_result):
-    flow = mock_flow({"func": callable_obj})
-    result = export_state(flow)
+def test_callable_serialization(callable_obj, expected_in_result):
+    result = to_serializable({"func": callable_obj})
     assert isinstance(result["func"], str)
     assert expected_in_result in result["func"].lower()
 
 
-def test_pydantic_model_serialization(mock_flow):
+def test_pydantic_model_serialization():
     address = Address(street="123 Main St", city="Tech City", country="Pythonia")
 
     person = Person(
@@ -109,23 +94,21 @@ def test_pydantic_model_serialization(mock_flow):
         skills=["Python", "Testing"],
     )
 
-    flow = mock_flow(
-        {
+    data = {
         "single_model": address,
         "nested_model": person,
         "model_list": [address, address],
         "model_dict": {"home": address},
     }
-    )
 
-    result = export_state(flow)
+    result = to_serializable(data)
     assert (
         to_string(result)
         == '{"single_model": {"street": "123 Main St", "city": "Tech City", "country": "Pythonia"}, "nested_model": {"name": "John Doe", "age": 30, "address": {"street": "123 Main St", "city": "Tech City", "country": "Pythonia"}, "birthday": "1994-01-01", "skills": ["Python", "Testing"]}, "model_list": [{"street": "123 Main St", "city": "Tech City", "country": "Pythonia"}, {"street": "123 Main St", "city": "Tech City", "country": "Pythonia"}], "model_dict": {"home": {"street": "123 Main St", "city": "Tech City", "country": "Pythonia"}}}'
     )
 
 
-def test_depth_limit(mock_flow):
+def test_depth_limit():
     """Test max depth handling with a deeply nested structure"""
 
     def create_nested(depth):
@@ -134,8 +117,7 @@ def test_depth_limit(mock_flow):
         return {"next": create_nested(depth - 1)}
 
     deep_structure = create_nested(10)
-    flow = mock_flow(deep_structure)
-    result = export_state(flow)
+    result = to_serializable(deep_structure)
 
     assert result == {
         "next": {