Ignore old messages middleware

functions/bot.ts

@@ -5,6 +5,7 @@ import { createAuthFailedResponse } from "./lib/json-response/create-auth-failed
 import { onMessage } from "./server-bot/on-message.ts";
 import { onCallbackQuery } from "./server-bot/on-callback-query.ts";
 import { onStart } from "./server-bot/on-start.ts";
+import { ignoreOldMessageMiddleware } from "./server-bot/ignore-old-messages-middleware.ts";
 
 export const onRequestPost: PagesFunction = handleError(
   async ({ env, request }) => {
@@ -15,6 +16,7 @@ export const onRequestPost: PagesFunction = handleError(
     }
 
     const bot = new Bot(envSafe.BOT_TOKEN);
+    bot.use(ignoreOldMessageMiddleware);
     bot.command("start", onStart);
     bot.on("message", onMessage(envSafe));
     bot.on("callback_query:data", onCallbackQuery(envSafe));

functions/server-bot/ignore-old-messages-middleware.ts

@@ -0,0 +1,21 @@
+import { Context, NextFunction } from "grammy";
+
+const threshold = 5 * 60; // 5 minutes
+export async function ignoreOldMessageMiddleware(
+  ctx: Context,
+  next: NextFunction
+): Promise<void> {
+  if (ctx.message) {
+    if (new Date().getTime() / 1000 - ctx.message.date < threshold) {
+      await next();
+    } else {
+      console.log(
+        `Ignoring message from ${ctx.from?.id ?? 'Unknown ID'} at ${
+          ctx.chat?.id ?? 'Unknown Chat ID'
+        } (${new Date().getTime() / 1000}:${ctx.message.date})`
+      );
+    }
+  } else {
+    await next();
+  }
+}