Fix config validation when elastic.apm is defined

src/core/server/config/ensure_valid_configuration.test.ts

@@ -16,14 +16,40 @@ describe('ensureValidConfiguration', () => {
   beforeEach(() => {
     jest.clearAllMocks();
     configService = configServiceMock.create();
-    configService.getUsedPaths.mockReturnValue(Promise.resolve(['core', 'elastic']));
+
+    configService.validate.mockResolvedValue();
+    configService.getUsedPaths.mockReturnValue(Promise.resolve([]));
   });
 
-  it('returns normally when there is no unused keys', async () => {
-    configService.getUnusedPaths.mockResolvedValue([]);
+  it('returns normally when there is no unused keys and when the config validates', async () => {
     await expect(ensureValidConfiguration(configService as any)).resolves.toBeUndefined();
   });
 
+  it('throws when config validation fails', async () => {
+    configService.validate.mockImplementation(() => {
+      throw new Error('some message');
+    });
+
+    await expect(ensureValidConfiguration(configService as any)).rejects.toMatchInlineSnapshot(
+      `[Error: some message]`
+    );
+  });
+
+  it('throws a `CriticalError` with the correct processExitCode value when config validation fails', async () => {
+    expect.assertions(2);
+
+    configService.validate.mockImplementation(() => {
+      throw new Error('some message');
+    });
+
+    try {
+      await ensureValidConfiguration(configService as any);
+    } catch (e) {
+      expect(e).toBeInstanceOf(CriticalError);
+      expect(e.processExitCode).toEqual(78);
+    }
+  });
+
   it('throws when there are some unused keys', async () => {
     configService.getUnusedPaths.mockResolvedValue(['some.key', 'some.other.key']);
 
@@ -44,4 +70,18 @@ describe('ensureValidConfiguration', () => {
       expect(e.processExitCode).toEqual(64);
     }
   });
+
+  it('does not throw when all unused keys are included in the ignored paths', async () => {
+    configService.getUnusedPaths.mockResolvedValue(['dev.someDevKey', 'elastic.apm.enabled']);
+
+    await expect(ensureValidConfiguration(configService as any)).resolves.toBeUndefined();
+  });
+
+  it('throws when only some keys are included in the ignored paths', async () => {
+    configService.getUnusedPaths.mockResolvedValue(['dev.someDevKey', 'some.key']);
+
+    await expect(ensureValidConfiguration(configService as any)).rejects.toMatchInlineSnapshot(
+      `[Error: Unknown configuration key(s): "some.key". Check for spelling errors and ensure that expected plugins are installed.]`
+    );
+  });
 });

src/core/server/config/ensure_valid_configuration.ts

@@ -9,22 +9,27 @@
 import { ConfigService } from '@kbn/config';
 import { CriticalError } from '../errors';
 
+const ignoredPaths = ['dev.', 'elastic.apm.'];
+
+const invalidConfigExitCode = 78;
+const legacyInvalidConfigExitCode = 64;
+
 export async function ensureValidConfiguration(configService: ConfigService) {
-  await configService.validate();
+  try {
+    await configService.validate();
+  } catch (e) {
+    throw new CriticalError(e.message, 'InvalidConfig', invalidConfigExitCode, e);
+  }
 
-  const unusedConfigKeys = await configService.getUnusedPaths();
+  const unusedPaths = await configService.getUnusedPaths();
+  const unusedConfigKeys = unusedPaths.filter((unusedPath) => {
+    return !ignoredPaths.some((ignoredPath) => unusedPath.startsWith(ignoredPath));
+  });
 
   if (unusedConfigKeys.length > 0) {
     const message = `Unknown configuration key(s): ${unusedConfigKeys
       .map((key) => `"${key}"`)
       .join(', ')}. Check for spelling errors and ensure that expected plugins are installed.`;
-    throw new InvalidConfigurationError(message);
-  }
-}
-
-class InvalidConfigurationError extends CriticalError {
-  constructor(message: string) {
-    super(message, 'InvalidConfig', 64);
-    Object.setPrototypeOf(this, InvalidConfigurationError.prototype);
+    throw new CriticalError(message, 'InvalidConfig', legacyInvalidConfigExitCode);
   }
 }

src/core/server/server.ts

@@ -36,7 +36,6 @@ import { config as cspConfig } from './csp';
 import { config as elasticsearchConfig } from './elasticsearch';
 import { config as httpConfig } from './http';
 import { config as loggingConfig } from './logging';
-import { config as devConfig } from './dev';
 import { config as kibanaConfig } from './kibana_config';
 import { savedObjectsConfig, savedObjectsMigrationConfig } from './saved_objects';
 import { config as uiSettingsConfig } from './ui_settings';
@@ -303,7 +302,6 @@ export class Server {
       loggingConfig,
       httpConfig,
       pluginsConfig,
-      devConfig,
       kibanaConfig,
       savedObjectsConfig,
       savedObjectsMigrationConfig,