Update email worker to reply to too long emails

Author: satwikkansal

email-worker/package-lock.json

@@ -11,6 +11,7 @@
 		"wrangler": "^4.20.3"
 	},
 	"dependencies": {
-		"postal-mime": "^2.4.3"
+		"postal-mime": "^2.4.3",
+		"mimetext": "^3.0.27"
 	}
 }

email-worker/package.json

@@ -2,6 +2,8 @@
 const API_ENDPOINT = "https://api.mxgo.ai/process-email";
 // const API_ENDPOINT = "https://f9cb-2401-4900-1f27-802d-9dc8-c5a1-9434-c1f1.ngrok-free.app/process-email"
 import PostalMime from 'postal-mime';
+import { EmailMessage } from "cloudflare:email";
+import { createMimeMessage } from "mimetext";
 
 // Helper function to calculate size of base64 string
 function base64Size(base64String) {
@@ -112,6 +114,32 @@ export default {
         responseText = "Your query is being processed.";
       } else if (response.status === 401) {
         responseText = "Please sign up first to use our service.";
+      } else if (response.status === 413) {
+        responseText = "Your email and attachments combined are too large to process. Please try with smaller attachments or contact support.";
+
+        // Send reply email for 413 error
+        try {
+          const replyMsg = createMimeMessage();
+          replyMsg.setHeader("In-Reply-To", message.headers.get("Message-ID"));
+          replyMsg.setSender({ name: "MXGo Support", addr: message.to });
+          replyMsg.setRecipient(message.from);
+          replyMsg.setSubject(`Re: ${subject}`);
+          replyMsg.addMessage({
+            contentType: 'text/plain',
+            data: responseText
+          });
+
+          const replyMessage = new EmailMessage(
+            message.to,
+            message.from,
+            replyMsg.asRaw()
+          );
+
+          await message.reply(replyMessage);
+          console.log("Sent 413 error reply email to:", message.from);
+        } catch (replyError) {
+          console.error("Error sending reply email:", replyError);
+        }
       } else {
         responseText = "There was an error processing your request. Please try again later.";
       }

email-worker/src/worker.js

@@ -1,7 +1,6 @@
 name = "mxgo-email-worker"
 main = "src/worker.js"
-compatibility_date = "2000-01-01"
+compatibility_date = "2024-09-23"
 workers_dev = true
 preview_urls = false
-compatibility_flags = [ "set_forwardable_email_full_headers" ]
-
+compatibility_flags = [ "set_forwardable_email_full_headers", "nodejs_compat" ]

email-worker/wrangler.toml

@@ -121,7 +121,6 @@ async def lifespan(_app: FastAPI):
 bearer_auth_scheme = HTTPBearer()
 
 
-
 @app.get("/health")
 async def health_check():
     """Health check endpoint for Docker and load balancers."""