fix: preserve content when promise is rejected with plain object

Author: FeironoX5

packages/javascript/src/addons/consoleCatcher.ts

@@ -189,6 +189,25 @@ export class ConsoleCatcher {
     this.consoleOutput.push(logEvent);
   }
 
+  /**
+   * Converts a promise rejection reason to a string message.
+   *
+   * String(obj) gives "[object Object]" and JSON.stringify("str")
+   * adds unwanted quotes.
+   *
+   * @param reason - The rejection reason from PromiseRejectionEvent
+   */
+  private stringifyReason(reason: unknown): string {
+    if (reason instanceof Error) {
+      return reason.message;
+    }
+    if (typeof reason === 'string') {
+      return reason;
+    }
+
+    return JSON.stringify(Sanitizer.sanitize(reason));
+  }
+
   /**
    * Creates a console log event from an error or promise rejection
    *
@@ -212,7 +231,7 @@ export class ConsoleCatcher {
       method: 'error',
       timestamp: new Date(),
       type: 'UnhandledRejection',
-      message: event.reason?.message || String(event.reason),
+      message: this.stringifyReason(event.reason),
       stack: event.reason?.stack || '',
       fileLine: '',
     };

packages/javascript/src/catcher.ts

@@ -14,7 +14,7 @@ import type {
 } from '@hawk.so/types';
 import type { JavaScriptCatcherIntegrations } from './types/integrations';
 import { EventRejectedError } from './errors';
-import { isErrorProcessed, markErrorAsProcessed } from './utils/event';
+import { isErrorProcessed, markErrorAsProcessed, getErrorFromEvent } from './utils/event';
 import { BrowserRandomGenerator } from './utils/random';
 import { ConsoleCatcher } from './addons/consoleCatcher';
 import { BreadcrumbManager } from './addons/breadcrumbs';
@@ -331,21 +331,7 @@ export default class Catcher {
       this.consoleCatcher!.addErrorEvent(event);
     }
 
-    /**
-     * Promise rejection reason is recommended to be an Error, but it can be a string:
-     * - Promise.reject(new Error('Reason message')) ——— recommended
-     * - Promise.reject('Reason message')
-     */
-    let error = (event as ErrorEvent).error || (event as PromiseRejectionEvent).reason;
-
-    /**
-     * Case when error triggered in external script
-     * We can't access event error object because of CORS
-     * Event message will be 'Script error.'
-     */
-    if (event instanceof ErrorEvent && error === undefined) {
-      error = (event as ErrorEvent).message;
-    }
+    const error = getErrorFromEvent(event);
 
     void this.formatAndSend(error);
   }

packages/javascript/src/utils/event.ts

@@ -1,4 +1,5 @@
 import { log } from '@hawk.so/core';
+import Sanitizer from '../modules/sanitizer';
 
 /**
  * Symbol to mark error as processed by Hawk
@@ -44,3 +45,38 @@ export function markErrorAsProcessed(error: unknown): void {
     log('Failed to mark error as processed', 'error', e);
   }
 }
+
+/**
+ * Extracts and normalizes error from ErrorEvent or PromiseRejectionEvent
+ *
+ * @param event - The error or promise rejection event
+ */
+export function getErrorFromEvent(event: ErrorEvent | PromiseRejectionEvent): Error | string {
+  /**
+   * Promise rejection reason is recommended to be an Error, but it can be a string:
+   * - Promise.reject(new Error('Reason message')) ——— recommended
+   * - Promise.reject('Reason message')
+   */
+  let error = (event as ErrorEvent).error || (event as PromiseRejectionEvent).reason;
+
+  /**
+   * Case when error triggered in external script
+   * We can't access event error object because of CORS
+   * Event message will be 'Script error.'
+   */
+  if (event instanceof ErrorEvent && error === undefined) {
+    error = (event as ErrorEvent).message;
+  }
+
+  /**
+   * Case when error rejected with an object
+   * Using a string instead of wrapping in Error is more natural,
+   * it doesn't fake the backtrace, also prefix added for dashboard readability
+   */
+  if (error instanceof Object && !(error instanceof Error) && event instanceof PromiseRejectionEvent) {
+    // Extra sanitize is needed to handle objects with circular references before JSON.stringify
+    error = `Promise rejected with ${JSON.stringify(Sanitizer.sanitize(error))}`;
+  }
+
+  return Sanitizer.sanitize(error);
+}