Enhance error handling in RSC modules by introducing extractErrorMessage utility

Author: AbanoubGhadban

node_package/src/RSCRequestTracker.ts

@@ -1,4 +1,5 @@
 import { PassThrough, Readable } from 'stream';
+import { extractErrorMessage } from './utils.ts';
 import {
   RSCPayloadStreamInfo,
   RSCPayloadCallback,
@@ -141,9 +142,7 @@ class RSCRequestTracker {
     } catch (error) {
       // Provide a more helpful error message that includes context
       throw new Error(
-        `Failed to generate RSC payload for component "${componentName}": ${
-          error instanceof Error ? error.message : String(error)
-        }`,
+        `Failed to generate RSC payload for component "${componentName}": ${extractErrorMessage(error)}`,
       );
     }
   }

node_package/src/getReactServerComponent.client.ts

@@ -1,6 +1,6 @@
 import * as React from 'react';
 import { createFromReadableStream } from 'react-on-rails-rsc/client.browser';
-import { createRSCPayloadKey, fetch, wrapInNewPromise } from './utils.ts';
+import { createRSCPayloadKey, fetch, wrapInNewPromise, extractErrorMessage } from './utils.ts';
 import transformRSCStreamAndReplayConsoleLogs from './transformRSCStreamAndReplayConsoleLogs.ts';
 import { RailsContext } from './types/index.ts';
 
@@ -65,17 +65,13 @@ const fetchRSC = ({
 
     return createFromFetch(fetch(fetchUrl)).catch((error: unknown) => {
       throw new Error(
-        `Failed to fetch RSC payload for component "${componentName}" from "${fetchUrl}": ${
-          error instanceof Error ? error.message : String(error)
-        }`,
+        `Failed to fetch RSC payload for component "${componentName}" from "${fetchUrl}": ${extractErrorMessage(error)}`,
       );
     });
   } catch (error: unknown) {
     // Handle JSON.stringify errors or other synchronous errors
     throw new Error(
-      `Failed to prepare RSC request for component "${componentName}": ${
-        error instanceof Error ? error.message : String(error)
-      }`,
+      `Failed to prepare RSC request for component "${componentName}": ${extractErrorMessage(error)}`,
     );
   }
 };

node_package/src/utils.ts

@@ -40,3 +40,7 @@ export const wrapInNewPromise = <T>(promise: Promise<T>) => {
     void promise.catch(reject);
   });
 };
+
+export const extractErrorMessage = (error: unknown): string => {
+  return error instanceof Error ? error.message : String(error);
+};