feat(core): add restart continuation message (#40989)

packages/core/src/session/execution/restart.ts

@@ -2,9 +2,14 @@ export * as SessionRestart from "./restart"
 
 import { Context, Effect, Layer } from "effect"
 import { makeGlobalNode } from "@opencode-ai/util/effect/app-node"
+import { Bus } from "../../bus"
+import { SessionEvent } from "../event"
 import { SessionExecution } from "../execution"
 import { SessionStore } from "../store"
 
+const CONTINUE_AFTER_SERVER_RESTART =
+  "The server restarted while you were working. Continue from where you left off without repeating completed work."
+
 export interface Interface {
   /**
    * Marks every execution active in this process for resumption by the next server start.
@@ -26,6 +31,7 @@ export const layer = Layer.effect(
   Effect.gen(function* () {
     const store = yield* SessionStore.Service
     const execution = yield* SessionExecution.Service
+    const bus = yield* Bus.Service
     return Service.of({
       suspendActiveSessions: Effect.gen(function* () {
         yield* store.suspend(yield* execution.active)
@@ -37,6 +43,11 @@ export const layer = Layer.effect(
           (sessionID) =>
             Effect.gen(function* () {
               if (!(yield* store.consumeSuspended(sessionID))) return
+              yield* bus.publish(SessionEvent.Synthetic, {
+                sessionID,
+                text: CONTINUE_AFTER_SERVER_RESTART,
+                description: "Continuing after restart",
+              })
               // Drain failures are already logged and durably recorded by the execution layer.
               yield* Effect.ignore(execution.resume(sessionID))
             }),
@@ -47,4 +58,8 @@ export const layer = Layer.effect(
   }),
 )
 
-export const node = makeGlobalNode({ service: Service, layer, deps: [SessionStore.node, SessionExecution.node] })
+export const node = makeGlobalNode({
+  service: Service,
+  layer,
+  deps: [SessionStore.node, SessionExecution.node, Bus.node],
+})

packages/core/test/session-execution.test.ts

@@ -13,6 +13,7 @@ import { Session } from "@opencode-ai/core/session"
 import { SessionExecution } from "@opencode-ai/core/session/execution"
 import { SessionRestart } from "@opencode-ai/core/session/execution/restart"
 import { UserInterruptedError } from "@opencode-ai/core/session/error"
+import { SessionEvent } from "@opencode-ai/core/session/event"
 import { SessionRunner } from "@opencode-ai/core/session/runner"
 import { SessionTable } from "@opencode-ai/core/session/sql"
 import { SessionStore } from "@opencode-ai/core/session/store"
@@ -127,23 +128,34 @@ describe("SessionExecution lifecycle", () => {
   it.effect("resumes each suspended Session at most once", () =>
     Effect.gen(function* () {
       const database = yield* Database.Service
+      const bus = yield* Bus.Service
       const first = Session.ID.make("ses_resume_first")
       const second = Session.ID.make("ses_resume_second")
       yield* seedSessions(database, [first, second], { time_suspended: Date.now() })
 
       const drained: string[] = []
+      const continued: SessionEvent.Synthetic[] = []
       const scope = yield* Scope.make()
       const context = yield* buildExecution(scope, ({ sessionID }) => Effect.sync(() => void drained.push(sessionID)))
       const execution = Context.get(context, SessionExecution.Service)
       const restart = Context.get(context, SessionRestart.Service)
+      yield* bus.project(SessionEvent.Synthetic, (event) => Effect.sync(() => void continued.push(event)))
 
       yield* restart.resumeSuspendedSessions
       yield* Effect.forEach([first, second], execution.awaitIdle, { discard: true })
       expect(drained.toSorted()).toEqual([first, second])
+      expect(continued.map((event) => event.data).toSorted((a, b) => a.sessionID.localeCompare(b.sessionID))).toEqual(
+        [first, second].map((sessionID) => ({
+          sessionID,
+          text: "The server restarted while you were working. Continue from where you left off without repeating completed work.",
+          description: "Continuing after restart",
+        })),
+      )
       expect(yield* suspensions(database)).toEqual({ [first]: false, [second]: false })
 
       yield* restart.resumeSuspendedSessions
       expect(drained.length).toBe(2)
+      expect(continued.length).toBe(2)
       yield* Scope.close(scope, Exit.void)
     }),
   )