refactor: decouple Anilist watch status updates from API endpoint to an asynchronous queue worker.

src/index.ts

@@ -5,6 +5,7 @@ import { maybeUpdateLastConnectedAt } from "~/controllers/maybeUpdateLastConnect
 import type { QueueName } from "~/libs/tasks/queueName.ts";
 
 import { onNewEpisode } from "./controllers/internal/new-episode";
+import { AnilistUpdateType } from "./libs/anilist/updateType";
 import type { QueueBody } from "./libs/tasks/queueTask";
 
 export const app = new OpenAPIHono<{ Bindings: Env }>();
@@ -74,7 +75,30 @@ export default {
   async queue(batch) {
     switch (batch.queue as QueueName) {
       case "ANILIST_UPDATES":
-        batch.retryAll();
+        for (const message of (
+          batch as MessageBatch<QueueBody["ANILIST_UPDATES"]>
+        ).messages) {
+          switch (message.body.updateType) {
+            case AnilistUpdateType.UpdateWatchStatus:
+              if (!message.body[AnilistUpdateType.UpdateWatchStatus]) {
+                throw new Error(
+                  `Discarding update, unknown body ${JSON.stringify(message.body)}`,
+                );
+              }
+
+              const { updateWatchStatusOnAnilist } =
+                await import("~/controllers/watch-status/anilist");
+              const payload = message.body[AnilistUpdateType.UpdateWatchStatus];
+              await updateWatchStatusOnAnilist(
+                payload.titleId,
+                payload.watchStatus,
+                payload.aniListToken,
+              );
+              break;
+          }
+
+          message.ack();
+        }
         break;
       case "NEW_EPISODE":
         for (const message of (batch as MessageBatch<QueueBody["NEW_EPISODE"]>)
@@ -89,9 +113,8 @@ export default {
     }
   },
   async scheduled(event, env, ctx) {
-    const { processDelayedTasks } = await import(
-      "~/libs/tasks/processDelayedTasks"
-    );
+    const { processDelayedTasks } =
+      await import("~/libs/tasks/processDelayedTasks");
     await processDelayedTasks(env, ctx);
   },
 } satisfies ExportedHandler<Env>;