[nodes] Add cancelation to the API

invokeai/app/api/routers/sessions.py

@@ -270,3 +270,18 @@ async def invoke_session(
 
     ApiDependencies.invoker.invoke(session, invoke_all=all)
     return Response(status_code=202)
+
+
+@session_router.delete(
+    "/{session_id}/invoke",
+    operation_id="cancel_session_invoke",
+    responses={
+        202: {"description": "The invocation is canceled"}
+    },
+)
+async def cancel_session_invoke(
+    session_id: str = Path(description="The id of the session to cancel"),
+) -> None:
+    """Invokes a session"""
+    ApiDependencies.invoker.cancel(session_id)
+    return Response(status_code=202)

invokeai/app/services/invocation_queue.py

@@ -2,6 +2,7 @@
 
 from abc import ABC, abstractmethod
 from queue import Queue
+import time
 
 
 # TODO: make this serializable
@@ -10,6 +11,7 @@ class InvocationQueueItem:
     graph_execution_state_id: str
     invocation_id: str
     invoke_all: bool
+    timestamp: float
 
     def __init__(
         self,
@@ -22,6 +24,7 @@ class InvocationQueueItem:
         self.graph_execution_state_id = graph_execution_state_id
         self.invocation_id = invocation_id
         self.invoke_all = invoke_all
+        self.timestamp = time.time()
 
 
 class InvocationQueueABC(ABC):
@@ -35,15 +38,44 @@ class InvocationQueueABC(ABC):
     def put(self, item: InvocationQueueItem | None) -> None:
         pass
 
+    @abstractmethod
+    def cancel(self, graph_execution_state_id: str) -> None:
+        pass
+
+    @abstractmethod
+    def is_canceled(self, graph_execution_state_id: str) -> bool:
+        pass
+
 
 class MemoryInvocationQueue(InvocationQueueABC):
     __queue: Queue
+    __cancellations: dict[str, float]
 
     def __init__(self):
         self.__queue = Queue()
+        self.__cancellations = dict()
 
     def get(self) -> InvocationQueueItem:
-        return self.__queue.get()
+        item = self.__queue.get()
+
+        while isinstance(item, InvocationQueueItem) \
+            and item.graph_execution_state_id in self.__cancellations \
+            and self.__cancellations[item.graph_execution_state_id] > item.timestamp:
+            item = self.__queue.get()
+
+        # Clear old items
+        for graph_execution_state_id in list(self.__cancellations.keys()):
+            if self.__cancellations[graph_execution_state_id] < item.timestamp:
+                del self.__cancellations[graph_execution_state_id]
+
+        return item
 
     def put(self, item: InvocationQueueItem | None) -> None:
         self.__queue.put(item)
+
+    def cancel(self, graph_execution_state_id: str) -> None:
+        if graph_execution_state_id not in self.__cancellations:
+            self.__cancellations[graph_execution_state_id] = time.time()
+
+    def is_canceled(self, graph_execution_state_id: str) -> bool:
+        return graph_execution_state_id in self.__cancellations

invokeai/app/services/invoker.py

@@ -50,6 +50,10 @@ class Invoker:
         new_state = GraphExecutionState(graph=Graph() if graph is None else graph)
         self.services.graph_execution_manager.set(new_state)
         return new_state
+    
+    def cancel(self, graph_execution_state_id: str) -> None:
+        """Cancels the given execution state"""
+        self.services.queue.cancel(graph_execution_state_id)
 
     def __start_service(self, service) -> None:
         # Call start() method on any services that have it

invokeai/app/services/processor.py

@@ -58,6 +58,12 @@ class DefaultInvocationProcessor(InvocationProcessorABC):
                         )
                     )
 
+                    # Check queue to see if this is canceled, and skip if so
+                    if self.__invoker.services.queue.is_canceled(
+                        graph_execution_state.id
+                    ):
+                        continue
+
                     # Save outputs and history
                     graph_execution_state.complete(invocation.id, outputs)
 
@@ -95,6 +101,12 @@ class DefaultInvocationProcessor(InvocationProcessorABC):
                     )
 
                     pass
+                
+                # Check queue to see if this is canceled, and skip if so
+                if self.__invoker.services.queue.is_canceled(
+                    graph_execution_state.id
+                ):
+                    continue
 
                 # Queue any further commands if invoking all
                 is_complete = graph_execution_state.is_complete()