fix: truncate large error messages before printing to customer (#2260)

* fix: truncate large error messages before printing to customer

* PR Updates

Author: Amplifiyer

.changeset/rude-wasps-look.md

@@ -0,0 +1,5 @@
+---
+'@aws-amplify/backend-deployer': patch
+---
+
+truncate large error messages before printing to customer

packages/backend-deployer/src/cdk_deployer.ts

@@ -199,14 +199,24 @@ export class CDKDeployer implements BackendDeployer {
       // However if the cdk process didn't run or produced no output, then we have nothing to go on with. So we throw
       // this error to aid in some debugging.
       if (aggregatedStderr.trim()) {
+        // If the string is more than 65KB, truncate and keep the last portion.
         // eslint-disable-next-line amplify-backend-rules/prefer-amplify-errors
-        throw new Error(aggregatedStderr);
+        throw new Error(this.truncateString(aggregatedStderr, 65000));
       } else {
         throw error;
       }
     }
   };
 
+  private truncateString = (str: string, size: number) => {
+    const encoder = new TextEncoder();
+    const decoder = new TextDecoder();
+    const encoded = encoder.encode(str);
+    return encoded.byteLength > size
+      ? '...truncated...' + decoder.decode(encoded.slice(-size))
+      : str;
+  };
+
   private getAppCommand = () =>
     this.packageManagerController.getCommand([
       'tsx',