feat: Always truncate stored breadcrumb messages to 2kb (#15819)

We had this logic in the console instrumentation before but it probably
makes sense to truncate all breadcrumbs to some degree for memory
consumption reasons.

Acts as prework for
#15818 because if we
don't truncate error messages they will end up as very big strings in
breadcrumbs.

Author: Luca Forstner

packages/core/src/scope.ts

@@ -24,6 +24,7 @@ import { isPlainObject } from './utils-hoist/is';
 import { logger } from './utils-hoist/logger';
 import { uuid4 } from './utils-hoist/misc';
 import { generateTraceId } from './utils-hoist/propagationContext';
+import { truncate } from './utils-hoist/string';
 import { dateTimestampInSeconds } from './utils-hoist/time';
 import { merge } from './utils/merge';
 import { _getSpanForScope, _setSpanForScope } from './utils/spanOnScope';
@@ -474,9 +475,11 @@ export class Scope {
       return this;
     }
 
-    const mergedBreadcrumb = {
+    const mergedBreadcrumb: Breadcrumb = {
       timestamp: dateTimestampInSeconds(),
       ...breadcrumb,
+      // Breadcrumb messages can theoretically be infinitely large and they're held in memory so we truncate them not to leak (too much) memory
+      message: breadcrumb.message ? truncate(breadcrumb.message, 2048) : breadcrumb.message,
     };
 
     this._breadcrumbs.push(mergedBreadcrumb);

packages/core/test/lib/scope.test.ts

@@ -186,6 +186,12 @@ describe('Scope', () => {
       expect(scope['_breadcrumbs']).toHaveLength(111);
     });
 
+    test('addBreadcrumb will truncate the stored messages', () => {
+      const scope = new Scope();
+      scope.addBreadcrumb({ message: 'A'.repeat(10_000) });
+      expect(scope['_breadcrumbs'][0]?.message).toBe(`${'A'.repeat(2048)}...`);
+    });
+
     test('setLevel', () => {
       const scope = new Scope();
       scope.setLevel('fatal');

packages/node/src/integrations/console.ts

@@ -5,7 +5,6 @@ import {
   defineIntegration,
   getClient,
   severityLevelFromString,
-  truncate,
 } from '@sentry/core';
 
 const INTEGRATION_NAME = 'Console';
@@ -26,7 +25,7 @@ export const consoleIntegration = defineIntegration(() => {
           {
             category: 'console',
             level: severityLevelFromString(level),
-            message: truncate(util.format.apply(undefined, args), 2048), // 2KB
+            message: util.format.apply(undefined, args),
           },
           {
             input: [...args],

packages/node/test/integration/console.test.ts

@@ -36,26 +36,4 @@ describe('Console integration', () => {
       },
     );
   });
-
-  it('should truncate breadcrumbs with more than 2 KB message size', () => {
-    consoleIntegration().setup?.(getClient() as NodeClient);
-
-    const longMsg = 'A'.repeat(10_000);
-
-    // eslint-disable-next-line no-console
-    console.log(longMsg);
-
-    expect(addBreadcrumbSpy).toHaveBeenCalledTimes(1);
-    expect(addBreadcrumbSpy).toHaveBeenCalledWith(
-      {
-        category: 'console',
-        level: 'log',
-        message: `${'A'.repeat(2048)}...`,
-      },
-      {
-        input: [longMsg],
-        level: 'log',
-      },
-    );
-  });
 });