fix(e-signer): file upload error handling

platforms/esigner-api/src/controllers/FileController.ts

@@ -2,8 +2,10 @@ import { Request, Response } from "express";
 import { FileService, ReservedFileNameError } from "../services/FileService";
 import multer from "multer";
 
+export const MAX_FILE_SIZE = 20 * 1024 * 1024; // 20MB limit
+
 const upload = multer({
-    limits: { fileSize: 10 * 1024 * 1024 }, // 10MB limit
+    limits: { fileSize: MAX_FILE_SIZE },
     storage: multer.memoryStorage(),
 });
 
@@ -200,7 +202,7 @@ export class FileController {
             }
 
             const signatures = await this.fileService.getFileSignatures(fileId);
-            
+
             res.json(signatures.map(sig => ({
                 id: sig.id,
                 userId: sig.userId,

platforms/esigner-api/src/index.ts

@@ -5,7 +5,8 @@ import { config } from "dotenv";
 import { AppDataSource } from "./database/data-source";
 import path from "path";
 import { AuthController } from "./controllers/AuthController";
-import { FileController } from "./controllers/FileController";
+import { FileController, MAX_FILE_SIZE } from "./controllers/FileController";
+import multer from "multer";
 import { InvitationController } from "./controllers/InvitationController";
 import { SignatureController } from "./controllers/SignatureController";
 import { UserController } from "./controllers/UserController";
@@ -24,12 +25,12 @@ AppDataSource.initialize()
     .then(async () => {
         console.log("Database connection established");
         console.log("Web3 adapter initialized");
-        
+
         // Initialize platform eVault for eSigner
         try {
             const platformService = PlatformEVaultService.getInstance();
             const exists = await platformService.checkPlatformEVaultExists();
-            
+
             if (!exists) {
                 console.log("🔧 Creating platform eVault for eSigner...");
                 const result = await platformService.createPlatformEVault();
@@ -61,8 +62,8 @@ app.use(
         credentials: true,
     }),
 );
-app.use(express.json({ limit: "50mb" }));
-app.use(express.urlencoded({ limit: "50mb", extended: true }));
+app.use(express.json({ limit: "20mb" }));
+app.use(express.urlencoded({ limit: "20mb", extended: true }));
 
 // Controllers
 const authController = new AuthController();
@@ -105,6 +106,27 @@ app.post("/api/signatures/session", authGuard, signatureController.createSigning
 app.get("/api/signatures/session/:id", signatureController.getSigningSessionStatus);
 app.post("/api/signatures/callback", signatureController.handleSignedPayload);
 
+// Global error handler for multer file size errors
+app.use((err: Error, req: express.Request, res: express.Response, next: express.NextFunction) => {
+    if (err instanceof multer.MulterError && err.code === "LIMIT_FILE_SIZE") {
+        const maxSizeMB = Math.round(MAX_FILE_SIZE / (1024 * 1024));
+        return res.status(413).json({
+            error: `File size exceeds the maximum limit of ${maxSizeMB} MB`,
+            code: "LIMIT_FILE_SIZE",
+            maxSize: MAX_FILE_SIZE,
+        });
+    }
+    // Handle other multer errors
+    if (err instanceof multer.MulterError) {
+        return res.status(400).json({
+            error: err.message,
+            code: err.code,
+        });
+    }
+    // Pass other errors to the default handler
+    next(err);
+});
+
 // Start server
 app.listen(port, () => {
     console.log(`eSigner API server running on port ${port}`);

platforms/esigner/src/lib/stores/files.ts

@@ -65,7 +65,25 @@ export const fetchDocuments = async () => {
 // Keep fetchFiles alias for backward compatibility
 export const fetchFiles = fetchDocuments;
 
+const MAX_FILE_SIZE = 20 * 1024 * 1024; // 20MB limit
+
+export class FileSizeError extends Error {
+	constructor(public fileSize: number, public maxSize: number = MAX_FILE_SIZE) {
+		const fileSizeMB = (fileSize / (1024 * 1024)).toFixed(2);
+		const maxSizeMB = (maxSize / (1024 * 1024)).toFixed(0);
+		super(`File size (${fileSizeMB} MB) exceeds the maximum limit of ${maxSizeMB} MB`);
+		this.name = 'FileSizeError';
+	}
+}
+
 export const uploadFile = async (file: File, displayName?: string, description?: string) => {
+	// Client-side file size validation
+	if (file.size > MAX_FILE_SIZE) {
+		const err = new FileSizeError(file.size, MAX_FILE_SIZE);
+		error.set(err.message);
+		throw err;
+	}
+
 	try {
 		isLoading.set(true);
 		error.set(null);
@@ -84,7 +102,20 @@ export const uploadFile = async (file: File, displayName?: string, description?:
 		});
 		await fetchDocuments();
 		return response.data;
-	} catch (err) {
+	} catch (err: unknown) {
+		// Handle HTTP 413 Payload Too Large
+		if (err && typeof err === 'object' && 'response' in err) {
+			const axiosError = err as { response?: { status?: number; data?: { error?: string; maxSize?: number; fileSize?: number } } };
+			if (axiosError.response?.status === 413) {
+				const data = axiosError.response.data;
+				const fileSizeErr = new FileSizeError(
+					data?.fileSize || file.size,
+					data?.maxSize || MAX_FILE_SIZE
+				);
+				error.set(fileSizeErr.message);
+				throw fileSizeErr;
+			}
+		}
 		error.set(err instanceof Error ? err.message : 'Failed to upload file');
 		throw err;
 	} finally {

platforms/esigner/src/routes/(protected)/files/new/+page.svelte

@@ -2,7 +2,7 @@
 	import { onMount } from 'svelte';
 	import { goto } from '$app/navigation';
 	import { isAuthenticated } from '$lib/stores/auth';
-	import { uploadFile } from '$lib/stores/files';
+	import { files, fetchFiles, uploadFile, FileSizeError } from '$lib/stores/files';
 	import { apiClient } from '$lib/utils/axios';
 	import { inviteSignees } from '$lib/stores/invitations';
 
@@ -59,7 +59,11 @@
 			}
 		} catch (err) {
 			console.error('Upload failed:', err);
-			alert('Failed to upload file');
+			if (err instanceof FileSizeError) {
+				alert(err.message);
+			} else {
+				alert('Failed to upload file. Please try again.');
+			}
 			throw err;
 		} finally {
 			isLoading = false;
@@ -126,7 +130,7 @@
 			alert('You cannot invite yourself. You are automatically added as a signee.');
 			return;
 		}
-		
+
 		if (!selectedUsers.find(u => u.id === user.id)) {
 			selectedUsers = [...selectedUsers, user];
 		}
@@ -147,10 +151,10 @@
 		try {
 			isSubmitting = true;
 			const userIds = selectedUsers.map(u => u.id);
-			
+
 			// Backend will automatically add owner as signee
 			await inviteSignees(selectedFile.id, userIds);
-			
+
 			goto(`/files/${selectedFile.id}`);
 		} catch (err) {
 			console.error('Failed to create invitations:', err);