Nexus cancellation types

core/src/worker/workflow/machines/nexus_operation_state_machine.rs

@@ -7,6 +7,8 @@ use crate::worker::workflow::{
 };
 use itertools::Itertools;
 use rustfsm::{MachineError, StateMachine, TransitionResult, fsm};
+use temporal_sdk_core_protos::coresdk::nexus::NexusOperationCancellationType;
+use temporal_sdk_core_protos::temporal::api::command::v1::command;
 use temporal_sdk_core_protos::{
     coresdk::{
         nexus::{NexusOperationResult, nexus_operation_result},
@@ -16,7 +18,7 @@ use temporal_sdk_core_protos::{
         workflow_commands::ScheduleNexusOperation,
     },
     temporal::api::{
-        command::v1::{RequestCancelNexusOperationCommandAttributes, command},
+        command::v1::RequestCancelNexusOperationCommandAttributes,
         common::v1::Payload,
         enums::v1::{CommandType, EventType},
         failure::v1::{self as failure, Failure, failure::FailureInfo},
@@ -54,6 +56,7 @@ fsm! {
       --(NexusOperationStarted(NexusOperationStartedEventAttributes), on_started)--> Started;
 
     Started --(Cancel, shared on_issue_cancel)--> Started;
+    Started --(Cancel, shared on_issue_cancel)--> Cancelled;
     Started --(CommandRequestCancelNexusOperation)--> Started;
     Started --(NexusOperationCancelRequested)--> Started;
     Started
@@ -65,10 +68,17 @@ fsm! {
     Started
       --(NexusOperationTimedOut(NexusOperationTimedOutEventAttributes), on_timed_out)--> TimedOut;
 
+    Cancelled --(Cancel)--> Cancelled;
+    Cancelled --(CommandRequestCancelNexusOperation)--> Cancelled;
+    Cancelled --(NexusOperationCancelRequested)--> Cancelled;
+    Cancelled --(NexusOperationCompleted(NexusOperationCompletedEventAttributes), shared on_completed)--> Cancelled;
+    Cancelled --(NexusOperationFailed(NexusOperationFailedEventAttributes), shared on_failed)--> Cancelled;
+    Cancelled --(NexusOperationTimedOut(NexusOperationTimedOutEventAttributes), shared on_timed_out)--> Cancelled;
+    Cancelled --(NexusOperationCanceled(NexusOperationCanceledEventAttributes))--> Cancelled;
+
     // Ignore cancels in all terminal states
     Completed --(Cancel)--> Completed;
     Failed --(Cancel)--> Failed;
-    Cancelled --(Cancel)--> Cancelled;
     TimedOut --(Cancel)--> TimedOut;
 }
 
@@ -102,6 +112,7 @@ pub(super) struct SharedState {
 
     cancelled_before_sent: bool,
     cancel_sent: bool,
+    cancel_type: NexusOperationCancellationType,
 }
 
 impl NexusOperationMachine {
@@ -116,6 +127,7 @@ impl NexusOperationMachine {
                 operation: attribs.operation.clone(),
                 cancelled_before_sent: false,
                 cancel_sent: false,
+                cancel_type: attribs.cancellation_type(),
             },
         );
         NewMachineWithCommand {
@@ -249,12 +261,20 @@ impl Started {
     pub(crate) fn on_issue_cancel(
         &self,
         ss: &mut SharedState,
-    ) -> NexusOperationMachineTransition<Started> {
+    ) -> NexusOperationMachineTransition<StartedOrCancelled> {
         if !ss.cancel_sent {
             ss.cancel_sent = true;
-            NexusOperationMachineTransition::commands([NexusOperationCommand::IssueCancel])
+            let dest = if matches!(
+                ss.cancel_type,
+                NexusOperationCancellationType::Abandon | NexusOperationCancellationType::TryCancel
+            ) {
+                StartedOrCancelled::Cancelled(Default::default())
+            } else {
+                StartedOrCancelled::Started(Default::default())
+            };
+            TransitionResult::ok([NexusOperationCommand::IssueCancel], dest)
         } else {
-            NexusOperationMachineTransition::default()
+            TransitionResult::ok([], StartedOrCancelled::Started(Default::default()))
         }
     }
 
@@ -315,6 +335,49 @@ pub(super) struct TimedOut;
 #[derive(Default, Clone)]
 pub(super) struct Cancelled;
 
+fn completion_of_not_abandoned_err() -> WFMachinesError {
+    WFMachinesError::Nondeterminism(
+        "Nexus operation which don't have the ABANDON cancellation type cannot complete after \
+         being cancelled."
+            .to_string(),
+    )
+}
+
+impl Cancelled {
+    pub(super) fn on_completed(
+        self,
+        ss: &mut SharedState,
+        _: NexusOperationCompletedEventAttributes,
+    ) -> NexusOperationMachineTransition<Cancelled> {
+        if ss.cancel_type == NexusOperationCancellationType::Abandon {
+            return NexusOperationMachineTransition::Err(completion_of_not_abandoned_err());
+        }
+        NexusOperationMachineTransition::ok([], self)
+    }
+
+    pub(super) fn on_failed(
+        self,
+        ss: &mut SharedState,
+        _: NexusOperationFailedEventAttributes,
+    ) -> NexusOperationMachineTransition<Cancelled> {
+        if ss.cancel_type == NexusOperationCancellationType::Abandon {
+            return NexusOperationMachineTransition::Err(completion_of_not_abandoned_err());
+        }
+        NexusOperationMachineTransition::ok([], self)
+    }
+
+    pub(super) fn on_timed_out(
+        self,
+        ss: &mut SharedState,
+        _: NexusOperationTimedOutEventAttributes,
+    ) -> NexusOperationMachineTransition<Cancelled> {
+        if ss.cancel_type == NexusOperationCancellationType::Abandon {
+            return NexusOperationMachineTransition::Err(completion_of_not_abandoned_err());
+        }
+        NexusOperationMachineTransition::ok([], self)
+    }
+}
+
 impl TryFrom<HistEventData> for NexusOperationMachineEvents {
     type Error = WFMachinesError;
 
@@ -497,14 +560,38 @@ impl WFMachinesAdapter for NexusOperationMachine {
                 ]
             }
             NexusOperationCommand::IssueCancel => {
-                vec![MachineResponse::IssueNewCommand(
-                    command::Attributes::RequestCancelNexusOperationCommandAttributes(
-                        RequestCancelNexusOperationCommandAttributes {
-                            scheduled_event_id: self.shared_state.scheduled_event_id,
-                        },
+                let mut resps = vec![];
+                if self.shared_state.cancel_type != NexusOperationCancellationType::Abandon {
+                    resps.push(MachineResponse::IssueNewCommand(
+                        command::Attributes::RequestCancelNexusOperationCommandAttributes(
+                            RequestCancelNexusOperationCommandAttributes {
+                                scheduled_event_id: self.shared_state.scheduled_event_id,
+                            },
+                        )
+                        .into(),
+                    ))
+                }
+                // Immediately resolve abandon/trycancel modes
+                if matches!(
+                    self.shared_state.cancel_type,
+                    NexusOperationCancellationType::Abandon
+                        | NexusOperationCancellationType::TryCancel
+                ) {
+                    resps.push(
+                        ResolveNexusOperation {
+                            seq: self.shared_state.lang_seq_num,
+                            result: Some(NexusOperationResult {
+                                status: Some(nexus_operation_result::Status::Cancelled(
+                                    self.cancelled_failure(
+                                        "Nexus operation cancelled after starting".to_owned(),
+                                    ),
+                                )),
+                            }),
+                        }
+                        .into(),
                     )
-                    .into(),
-                )]
+                }
+                resps
             }
         })
     }

sdk-core-protos/protos/local/temporal/sdk/core/nexus/nexus.proto

@@ -68,4 +68,19 @@ enum NexusTaskCancelReason {
     TIMED_OUT = 0;
     // The worker is shutting down
     WORKER_SHUTDOWN = 1;
-}
+}
+
+// Controls at which point to report back to lang when a nexus operation is cancelled
+enum NexusOperationCancellationType {
+    // Do not request cancellation of the nexus operation if already scheduled
+    ABANDON = 0;
+
+    // Initiate a cancellation request for the Nexus operation and immediately report cancellation
+    // to the caller. Note that it doesn't guarantee that cancellation is delivered to the operation if calling workflow exits before the delivery is done.
+    // If you want to ensure that cancellation is delivered to the operation, use WAIT_CANCELLATION_REQUESTED.
+    TRY_CANCEL = 1;
+    // Request cancellation of the operation and wait for confirmation that the request was received.
+    WAIT_CANCELLATION_REQUESTED = 2;
+    // Wait for operation cancellation completion. Default.
+    WAIT_CANCELLATION_COMPLETED = 3;
+}

sdk-core-protos/protos/local/temporal/sdk/core/workflow_commands/workflow_commands.proto

@@ -16,6 +16,7 @@ import "temporal/api/enums/v1/workflow.proto";
 import "temporal/api/failure/v1/message.proto";
 import "temporal/api/sdk/v1/user_metadata.proto";
 import "temporal/sdk/core/child_workflow/child_workflow.proto";
+import "temporal/sdk/core/nexus/nexus.proto";
 import "temporal/sdk/core/common/common.proto";
 
 message WorkflowCommand {
@@ -375,6 +376,8 @@ message ScheduleNexusOperation {
     // activities and child workflows, these are transmitted to Nexus operations that may be
     // external and are not traditional payloads.
     map<string, string> nexus_header = 7;
+    // Defines behaviour of the underlying nexus operation when operation cancellation has been requested.
+    nexus.NexusOperationCancellationType cancellation_type = 8;
 }
 
 // Request cancellation of a nexus operation started via `ScheduleNexusOperation`

sdk/src/workflow_context/options.rs

@@ -1,6 +1,7 @@
 use std::{collections::HashMap, time::Duration};
 
 use temporal_client::{Priority, WorkflowOptions};
+use temporal_sdk_core_protos::coresdk::nexus::NexusOperationCancellationType;
 use temporal_sdk_core_protos::{
     coresdk::{
         child_workflow::ChildWorkflowCancellationType,
@@ -397,6 +398,8 @@ pub struct NexusOperationOptions {
     /// activities and child workflows, these are transmitted to Nexus operations that may be
     /// external and are not traditional payloads.
     pub nexus_header: HashMap<String, String>,
+    /// Cancellation type for the operation
+    pub cancellation_type: Option<NexusOperationCancellationType>,
 }
 
 impl IntoWorkflowCommand for NexusOperationOptions {
@@ -414,6 +417,10 @@ impl IntoWorkflowCommand for NexusOperationOptions {
                         .schedule_to_close_timeout
                         .and_then(|t| t.try_into().ok()),
                     nexus_header: self.nexus_header,
+                    cancellation_type: self
+                        .cancellation_type
+                        .unwrap_or(NexusOperationCancellationType::WaitCancellationCompleted)
+                        .into(),
                 }
                 .into(),
             ),