[wip] workflow cancellation policy

web/src/pages/actions/WorkflowBuilderPage.tsx

@@ -40,6 +40,7 @@ import type {
   WorkflowBuilderState,
   PaletteAction,
   TransitionPreset,
+  CancellationPolicy,
 } from "@/types/workflow";
 import {
   generateUniqueTaskName,
@@ -53,6 +54,7 @@ import {
   removeTaskFromTransitions,
   renameTaskInTransitions,
   findStartingTaskIds,
+  CANCELLATION_POLICY_LABELS,
 } from "@/types/workflow";
 
 const INITIAL_STATE: WorkflowBuilderState = {
@@ -67,6 +69,7 @@ const INITIAL_STATE: WorkflowBuilderState = {
   tasks: [],
   tags: [],
   enabled: true,
+  cancellationPolicy: "allow_finish",
 };
 
 export default function WorkflowBuilderPage() {
@@ -135,6 +138,7 @@ export default function WorkflowBuilderPage() {
       const name =
         refParts.length > 1 ? refParts.slice(1).join(".") : workflow.ref;
 
+      const defn = workflow.definition as Record<string, unknown> | undefined;
       const builderState = definitionToBuilderState(
         {
           ref: workflow.ref,
@@ -143,10 +147,15 @@ export default function WorkflowBuilderPage() {
           version: workflow.version,
           parameters: workflow.param_schema || undefined,
           output: workflow.out_schema || undefined,
-          tasks:
-            ((workflow.definition as Record<string, unknown>)
-              ?.tasks as WorkflowYamlDefinition["tasks"]) || [],
+          vars: (defn?.vars as Record<string, unknown>) || undefined,
+          tasks: (defn?.tasks as WorkflowYamlDefinition["tasks"]) || [],
+          output_map: (defn?.output_map as Record<string, string>) || undefined,
           tags: workflow.tags,
+          cancellation_policy:
+            (defn?.cancellation_policy as
+              | "allow_finish"
+              | "cancel_running"
+              | undefined) || undefined,
         },
         workflow.pack_ref,
         name,
@@ -843,6 +852,24 @@ export default function WorkflowBuilderPage() {
               />
               Enabled
             </label>
+            <select
+              value={state.cancellationPolicy}
+              onChange={(e) =>
+                updateMetadata({
+                  cancellationPolicy: e.target.value as CancellationPolicy,
+                })
+              }
+              className="px-2 py-1 border border-gray-200 rounded text-xs text-gray-600 focus:ring-1 focus:ring-blue-500 focus:border-blue-500 bg-white"
+              title="Cancellation policy: controls how running tasks behave when the workflow is cancelled"
+            >
+              {Object.entries(CANCELLATION_POLICY_LABELS).map(
+                ([value, label]) => (
+                  <option key={value} value={value}>
+                    {label}
+                  </option>
+                ),
+              )}
+            </select>
           </div>
         </div>
       </div>

web/src/types/workflow.ts

@@ -185,6 +185,23 @@ export interface WorkflowEdge {
   labelPosition?: number;
 }
 
+/**
+ * Cancellation policy for a workflow.
+ *
+ * Controls what happens to running tasks when a workflow is cancelled:
+ * - `allow_finish` (default): Running tasks complete naturally; only
+ *   pending/requested tasks are cancelled and no new tasks are dispatched.
+ * - `cancel_running`: All running and pending tasks are forcefully cancelled.
+ *   Running processes receive SIGINT → SIGTERM → SIGKILL via the worker.
+ */
+export type CancellationPolicy = "allow_finish" | "cancel_running";
+
+/** Human-readable labels for each cancellation policy */
+export const CANCELLATION_POLICY_LABELS: Record<CancellationPolicy, string> = {
+  allow_finish: "Allow running tasks to finish",
+  cancel_running: "Cancel running tasks",
+};
+
 /** Complete workflow builder state */
 export interface WorkflowBuilderState {
   /** Workflow name (used to derive ref and filename) */
@@ -209,6 +226,8 @@ export interface WorkflowBuilderState {
   tags: string[];
   /** Whether the workflow is enabled */
   enabled: boolean;
+  /** Cancellation policy (default: allow_finish) */
+  cancellationPolicy: CancellationPolicy;
 }
 
 /** Parameter definition in flat schema format */
@@ -238,6 +257,7 @@ export interface WorkflowYamlDefinition {
   tasks: WorkflowYamlTask[];
   output_map?: Record<string, string>;
   tags?: string[];
+  cancellation_policy?: CancellationPolicy;
 }
 
 /**
@@ -252,6 +272,7 @@ export interface WorkflowGraphDefinition {
   vars?: Record<string, unknown>;
   tasks: WorkflowYamlTask[];
   output_map?: Record<string, string>;
+  cancellation_policy?: CancellationPolicy;
 }
 
 /**
@@ -450,6 +471,10 @@ export function builderStateToDefinition(
     definition.tags = state.tags;
   }
 
+  if (state.cancellationPolicy !== "allow_finish") {
+    definition.cancellation_policy = state.cancellationPolicy;
+  }
+
   return definition;
 }
 
@@ -537,6 +562,10 @@ export function builderStateToGraph(
     graph.vars = state.vars;
   }
 
+  if (state.cancellationPolicy !== "allow_finish") {
+    graph.cancellation_policy = state.cancellationPolicy;
+  }
+
   return graph;
 }
 
@@ -723,6 +752,7 @@ export function definitionToBuilderState(
     tasks,
     tags: definition.tags || [],
     enabled: true,
+    cancellationPolicy: definition.cancellation_policy || "allow_finish",
   };
 }