Update

fresh.gen.ts

@@ -5,7 +5,7 @@
 import config from "./deno.json" assert { type: "json" };
 import * as $0 from "./routes/api/config.ts";
 import * as $1 from "./routes/api/export/gallery/zip/[gid].ts";
-import * as $2 from "./routes/api/task/list.ts";
+import * as $2 from "./routes/api/task.ts";
 import * as $3 from "./routes/index.tsx";
 import * as $$0 from "./islands/Container.tsx";
 import * as $$1 from "./islands/Settings.tsx";
@@ -14,7 +14,7 @@ const manifest = {
     routes: {
         "./routes/api/config.ts": $0,
         "./routes/api/export/gallery/zip/[gid].ts": $1,
-        "./routes/api/task/list.ts": $2,
+        "./routes/api/task.ts": $2,
         "./routes/index.tsx": $3,
     },
     islands: {

routes/api/task.ts

@@ -0,0 +1,37 @@
+import { Handlers } from "$fresh/server.ts";
+import { get_task_manager } from "../../server.ts";
+import { Task } from "../../task.ts";
+
+export const handler: Handlers<Task[]> = {
+    GET(req, _ctx) {
+        const t = get_task_manager();
+        const { socket, response } = Deno.upgradeWebSocket(req);
+        const new_task_handle = (e: CustomEvent<Task>) => {
+            socket.send(JSON.stringify({ type: "new_task", detail: e.detail }));
+        };
+        const removeListener = () => {
+            t.removeEventListener("new_task", new_task_handle);
+        };
+        socket.onclose = () => {
+            removeListener();
+        };
+        socket.onerror = () => {
+            removeListener();
+            console.error("WebSocket error.");
+        };
+        socket.onmessage = (e) => {
+            try {
+                const d = JSON.parse(e.data);
+                if (d.type == "close") {
+                    socket.close();
+                }
+            } catch (_) {
+                null;
+            }
+        };
+        socket.onopen = () => {
+            t.addEventListener("new_task", new_task_handle);
+        };
+        return response;
+    },
+};

routes/api/task/list.ts

@@ -1,13 +0,0 @@
-import { Handlers } from "$fresh/server.ts";
-import { get_task_manager } from "../../../server.ts";
-import { Task } from "../../../task.ts";
-
-export const handler: Handlers<Task[]> = {
-    async GET(_, _ctx) {
-        const t = get_task_manager();
-        const tasks = await t.db.get_tasks_by_pid(Deno.pid);
-        return new Response(JSON.stringify(tasks), {
-            headers: { "Content-Type": "application/json" },
-        });
-    },
-};

task_manager.ts

@@ -15,7 +15,11 @@ import { promiseState, PromiseStatus, sleep } from "./utils.ts";
 export class AlreadyClosedError extends Error {
 }
 
-export class TaskManager {
+type EventMap = {
+    new_task: CustomEvent<Task>;
+};
+
+export class TaskManager extends EventTarget {
     #closed = false;
     cfg;
     client;
@@ -25,6 +29,7 @@ export class TaskManager {
     #abort;
     #force_abort;
     constructor(cfg: Config) {
+        super();
         this.cfg = cfg;
         this.#abort = new AbortController();
         this.#force_abort = new AbortController();
@@ -40,6 +45,14 @@ export class TaskManager {
     abort(reason?: unknown) {
         this.#abort.abort(reason);
     }
+    // @ts-ignore Checked type
+    addEventListener<T extends keyof EventMap>(
+        type: T,
+        callback: ((e: EventMap[T]) => void | Promise<void>) | null,
+        options?: boolean | AddEventListenerOptions,
+    ): void {
+        super.addEventListener(type, <EventListener | null> callback, options);
+    }
     get aborted() {
         return this.#abort.signal.aborted;
     }
@@ -131,6 +144,18 @@ export class TaskManager {
     get force_aborts() {
         return this.#force_abort.signal;
     }
+    // @ts-ignore Checked type
+    removeEventListener<T extends keyof EventMap>(
+        type: T,
+        callback: ((e: EventMap[T]) => void | Promise<void>) | null,
+        options?: boolean | EventListenerOptions,
+    ): void {
+        super.removeEventListener(
+            type,
+            <EventListener | null> callback,
+            options,
+        );
+    }
     async run() {
         if (this.aborted || this.force_aborted) throw new AlreadyClosedError();
         this.#check_closed();