Log uncaughtExceptions in our logging system

packages/core/environment/core-environment-server-internal/src/environment_service.test.ts

@@ -8,7 +8,7 @@
 
 import { BehaviorSubject } from 'rxjs';
 
-import type { CoreContext } from '@kbn/core-base-server-internal';
+import { type CoreContext, CriticalError } from '@kbn/core-base-server-internal';
 import type { AnalyticsServicePreboot } from '@kbn/core-analytics-server';
 
 import { EnvironmentService } from './environment_service';
@@ -127,36 +127,58 @@ describe('UuidService', () => {
         warning.name = 'DeprecationWarning';
         process.emit('warning', warning);
 
-        expect(logger.get('process').warn).not.toHaveBeenCalled();
+        expect(logger.get('environment').warn).not.toHaveBeenCalled();
       });
     });
 
-    // TODO: From Nodejs v16 emitting an unhandledRejection will kill the process
-    describe.skip('unhandledRejection warnings', () => {
-      it('logs warn for an unhandeld promise rejected with an Error', async () => {
+    describe('unhandledRejection warnings', () => {
+      it('logs warn for an unhandled promise rejected with an Error', async () => {
         await service.preboot({ analytics });
 
         const err = new Error('something went wrong');
-        process.emit('unhandledRejection', err, new Promise((res, rej) => rej(err)));
+        process.emit('unhandledRejection', err, new Promise((res, rej) => {}));
 
-        expect(logger.get('process').warn).toHaveBeenCalledTimes(1);
+        expect(logger.get('environment').warn).toHaveBeenCalledTimes(1);
         expect(loggingSystemMock.collect(logger).warn[0][0]).toMatch(
           /Detected an unhandled Promise rejection: Error: something went wrong\n.*at /
         );
       });
 
-      it('logs warn for an unhandeld promise rejected with a string', async () => {
+      it('logs warn for an unhandled promise rejected with a string', async () => {
         await service.preboot({ analytics });
 
         const err = 'something went wrong';
-        process.emit('unhandledRejection', err, new Promise((res, rej) => rej(err)));
+        process.emit('unhandledRejection', err, new Promise((res, rej) => {}));
 
-        expect(logger.get('process').warn).toHaveBeenCalledTimes(1);
+        expect(logger.get('environment').warn).toHaveBeenCalledTimes(1);
         expect(loggingSystemMock.collect(logger).warn[0][0]).toMatch(
           /Detected an unhandled Promise rejection: "something went wrong"/
         );
       });
     });
+
+    describe('uncaughtException warnings', () => {
+      it('logs warn for an uncaught exception with an Error', async () => {
+        await service.preboot({ analytics });
+
+        const err = new Error('something went wrong');
+        process.emit('uncaughtExceptionMonitor', err); // Types won't allow me to provide the `origin`
+
+        expect(logger.get('environment').warn).toHaveBeenCalledTimes(1);
+        expect(loggingSystemMock.collect(logger).warn[0][0]).toMatch(
+          /Detected an undefined: Error: something went wrong\n.*at /
+        );
+      });
+
+      it('does not log warn for an uncaught exception with a CriticalError', async () => {
+        await service.preboot({ analytics });
+
+        const err = new CriticalError('something went wrong', 'ERROR_CODE', 1234);
+        process.emit('uncaughtExceptionMonitor', err); // Types won't allow me to provide the `origin`
+
+        expect(logger.get('environment').warn).toHaveBeenCalledTimes(0);
+      });
+    });
   });
 
   describe('#setup()', () => {

packages/core/environment/core-environment-server-internal/src/environment_service.ts

@@ -10,7 +10,7 @@ import { firstValueFrom, of } from 'rxjs';
 import { PathConfigType, config as pathConfigDef } from '@kbn/utils';
 import type { Logger } from '@kbn/logging';
 import type { IConfigService } from '@kbn/config';
-import { CoreContext, coreConfigPaths } from '@kbn/core-base-server-internal';
+import { CoreContext, coreConfigPaths, CriticalError } from '@kbn/core-base-server-internal';
 import type { AnalyticsServicePreboot } from '@kbn/core-analytics-server';
 import { HttpConfigType } from './types';
 import { PidConfigType, pidConfig as pidConfigDef } from './pid_config';
@@ -56,7 +56,7 @@ export class EnvironmentService {
 
   public async preboot({ analytics }: EnvironmentServicePrebootDeps) {
     // IMPORTANT: This code is based on the assumption that none of the configuration values used
-    // here is supposed to change during preboot phase and it's safe to read them only once.
+    // here is supposed to change during preboot phase, and it's safe to read them only once.
     const [pathConfig, serverConfig, pidConfig] = await Promise.all([
       firstValueFrom(this.configService.atPath<PathConfigType>(pathConfigDef.path)),
       firstValueFrom(this.configService.atPath<HttpConfigType>(coreConfigPaths.http)),
@@ -68,6 +68,14 @@ export class EnvironmentService {
       const message = (reason as Error)?.stack ?? JSON.stringify(reason);
       this.log.warn(`Detected an unhandled Promise rejection: ${message}`);
     });
+    // Log uncaughtExceptions in our logger before crashing the process: https://github.com/elastic/kibana/issues/183182
+    process.on('uncaughtExceptionMonitor', (error, origin) => {
+      // CriticalErrors are handled in a different path
+      if (!(error instanceof CriticalError)) {
+        const message = error?.stack ?? JSON.stringify(error);
+        this.log.warn(`Detected an ${origin}: ${message}`);
+      }
+    });
 
     await createDataFolder({ pathConfig, logger: this.log });
     await writePidFile({ pidConfig, logger: this.log });