Move src/apm.js to @kbn/apm-config-loader (#94315) (#94538)

* Move src/apm.js to @kbn/apm-config-loader

* add unit tests for `initApm`

* return undefined instead of empty config

* use ?.

packages/kbn-apm-config-loader/src/config_loader.ts

@@ -8,13 +8,16 @@
 
 import { getConfigurationFilePaths, getConfigFromFiles, applyConfigOverrides } from './utils';
 import { ApmConfiguration } from './config';
+import { ApmAgentConfig } from './types';
+
+let apmConfig: ApmConfiguration | undefined;
 
 /**
  * Load the APM configuration.
  *
  * @param argv the `process.argv` arguments
  * @param rootDir The root directory of kibana (where the sources and the `package.json` file are)
- * @param production true for production builds, false otherwise
+ * @param isDistributable true for production builds, false otherwise
  */
 export const loadConfiguration = (
   argv: string[],
@@ -24,5 +27,19 @@ export const loadConfiguration = (
   const configPaths = getConfigurationFilePaths(argv);
   const rawConfiguration = getConfigFromFiles(configPaths);
   applyConfigOverrides(rawConfiguration, argv);
-  return new ApmConfiguration(rootDir, rawConfiguration, isDistributable);
+
+  apmConfig = new ApmConfiguration(rootDir, rawConfiguration, isDistributable);
+  return apmConfig;
+};
+
+export const getConfiguration = (serviceName: string): ApmAgentConfig | undefined => {
+  // integration test runner starts a kibana server that import the module without initializing APM.
+  // so we need to check initialization of the config.
+  // note that we can't just load the configuration during this module's import
+  // because jest IT are ran with `--config path-to-jest-config.js` which conflicts with the CLI's `config` arg
+  // causing the config loader to try to load the jest js config as yaml and throws.
+  if (apmConfig) {
+    return apmConfig.getConfig(serviceName);
+  }
+  return undefined;
 };

packages/kbn-apm-config-loader/src/index.ts

@@ -6,6 +6,7 @@
  * Side Public License, v 1.
  */
 
-export { loadConfiguration } from './config_loader';
+export { getConfiguration } from './config_loader';
+export { initApm } from './init_apm';
 export type { ApmConfiguration } from './config';
 export type { ApmAgentConfig } from './types';

packages/kbn-apm-config-loader/src/init_apm.test.mocks.ts

@@ -0,0 +1,12 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+export const mockLoadConfiguration = jest.fn();
+jest.doMock('./config_loader', () => ({
+  loadConfiguration: mockLoadConfiguration,
+}));

packages/kbn-apm-config-loader/src/init_apm.test.ts

@@ -0,0 +1,66 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+import { mockLoadConfiguration } from './init_apm.test.mocks';
+
+import { initApm } from './init_apm';
+import apm from 'elastic-apm-node';
+
+describe('initApm', () => {
+  let apmAddFilterSpy: jest.SpyInstance;
+  let apmStartSpy: jest.SpyInstance;
+  let getConfig: jest.Mock;
+
+  beforeEach(() => {
+    apmAddFilterSpy = jest.spyOn(apm, 'addFilter').mockImplementation(() => undefined);
+    apmStartSpy = jest.spyOn(apm, 'start').mockImplementation(() => undefined as any);
+    getConfig = jest.fn();
+
+    mockLoadConfiguration.mockImplementation(() => ({
+      getConfig,
+    }));
+  });
+
+  afterEach(() => {
+    jest.restoreAllMocks();
+    mockLoadConfiguration.mockReset();
+  });
+
+  it('calls `loadConfiguration` with the correct options', () => {
+    initApm(['foo', 'bar'], 'rootDir', true, 'service-name');
+
+    expect(mockLoadConfiguration).toHaveBeenCalledTimes(1);
+    expect(mockLoadConfiguration).toHaveBeenCalledWith(['foo', 'bar'], 'rootDir', true);
+  });
+
+  it('calls `apmConfigLoader.getConfig` with the correct options', () => {
+    initApm(['foo', 'bar'], 'rootDir', true, 'service-name');
+
+    expect(getConfig).toHaveBeenCalledTimes(1);
+    expect(getConfig).toHaveBeenCalledWith('service-name');
+  });
+
+  it('registers a filter using `addFilter`', () => {
+    initApm(['foo', 'bar'], 'rootDir', true, 'service-name');
+
+    expect(apmAddFilterSpy).toHaveBeenCalledTimes(1);
+    expect(apmAddFilterSpy).toHaveBeenCalledWith(expect.any(Function));
+  });
+
+  it('starts apm with the config returned from `getConfig`', () => {
+    const config = {
+      foo: 'bar',
+    };
+    getConfig.mockReturnValue(config);
+
+    initApm(['foo', 'bar'], 'rootDir', true, 'service-name');
+
+    expect(apmStartSpy).toHaveBeenCalledTimes(1);
+    expect(apmStartSpy).toHaveBeenCalledWith(config);
+  });
+});

packages/kbn-apm-config-loader/src/init_apm.ts

@@ -0,0 +1,39 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+import { loadConfiguration } from './config_loader';
+
+export const initApm = (
+  argv: string[],
+  rootDir: string,
+  isDistributable: boolean,
+  serviceName: string
+) => {
+  const apmConfigLoader = loadConfiguration(argv, rootDir, isDistributable);
+  const apmConfig = apmConfigLoader.getConfig(serviceName);
+
+  // we want to only load the module when effectively used
+  // eslint-disable-next-line @typescript-eslint/no-var-requires
+  const apm = require('elastic-apm-node');
+
+  // Filter out all user PII
+  apm.addFilter((payload: Record<string, any>) => {
+    try {
+      if (payload.context?.user && typeof payload.context.user === 'object') {
+        Object.keys(payload.context.user).forEach((key) => {
+          payload.context.user[key] = '[REDACTED]';
+        });
+      }
+    } catch (e) {
+      // just silently ignore the error
+    }
+    return payload;
+  });
+
+  apm.start(apmConfig);
+};

src/apm.js

@@ -1,52 +0,0 @@
-/*
- * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
- * or more contributor license agreements. Licensed under the Elastic License
- * 2.0 and the Server Side Public License, v 1; you may not use this file except
- * in compliance with, at your election, the Elastic License 2.0 or the Server
- * Side Public License, v 1.
- */
-
-const { join } = require('path');
-const { name, build } = require('../package.json');
-const { loadConfiguration } = require('@kbn/apm-config-loader');
-
-const ROOT_DIR = join(__dirname, '..');
-let apmConfig;
-
-/**
- * Flag to disable APM RUM support on all kibana builds by default
- */
-const isKibanaDistributable = Boolean(build && build.distributable === true);
-
-module.exports = function (serviceName = name) {
-  apmConfig = loadConfiguration(process.argv, ROOT_DIR, isKibanaDistributable);
-  const conf = apmConfig.getConfig(serviceName);
-  const apm = require('elastic-apm-node');
-
-  // Filter out all user PII
-  apm.addFilter((payload) => {
-    try {
-      if (payload.context && payload.context.user && typeof payload.context.user === 'object') {
-        Object.keys(payload.context.user).forEach((key) => {
-          payload.context.user[key] = '[REDACTED]';
-        });
-      }
-    } finally {
-      return payload;
-    }
-  });
-
-  apm.start(conf);
-};
-
-module.exports.getConfig = (serviceName) => {
-  // integration test runner starts a kibana server that import the module without initializing APM.
-  // so we need to check initialization of the config.
-  // note that we can't just load the configuration during this module's import
-  // because jest IT are ran with `--config path-to-jest-config.js` which conflicts with the CLI's `config` arg
-  // causing the config loader to try to load the jest js config as yaml and throws.
-  if (apmConfig) {
-    return apmConfig.getConfig(serviceName);
-  }
-  return {};
-};

src/cli/apm.js

@@ -0,0 +1,18 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+const { join } = require('path');
+const { name, build } = require('../../package.json');
+const { initApm } = require('@kbn/apm-config-loader');
+
+const rootDir = join(__dirname, '../..');
+const isKibanaDistributable = Boolean(build && build.distributable === true);
+
+module.exports = function (serviceName = name) {
+  initApm(process.argv, rootDir, isKibanaDistributable, serviceName);
+};

src/cli/dev.js

@@ -6,7 +6,7 @@
  * Side Public License, v 1.
  */
 
-require('../apm')(process.env.ELASTIC_APM_SERVICE_NAME || 'kibana-proxy');
+require('./apm')(process.env.ELASTIC_APM_SERVICE_NAME || 'kibana-proxy');
 require('../setup_node_env');
 require('../setup_node_env/root');
 require('./cli');

src/cli/dist.js

@@ -6,7 +6,7 @@
  * Side Public License, v 1.
  */
 
-require('../apm')();
+require('./apm')();
 require('../setup_node_env/dist');
 require('../setup_node_env/root');
 require('./cli');

src/core/server/http_resources/get_apm_config.test.mocks.ts

@@ -6,9 +6,9 @@
  * Side Public License, v 1.
  */
 
-export const getConfigMock = jest.fn();
-jest.doMock('../../../apm', () => ({
-  getConfig: getConfigMock,
+export const getConfigurationMock = jest.fn();
+jest.doMock('@kbn/apm-config-loader', () => ({
+  getConfiguration: getConfigurationMock,
 }));
 
 export const agentMock = {} as Record<string, any>;

src/core/server/http_resources/get_apm_config.test.ts

@@ -6,7 +6,7 @@
  * Side Public License, v 1.
  */
 
-import { getConfigMock, agentMock } from './get_apm_config.test.mocks';
+import { getConfigurationMock, agentMock } from './get_apm_config.test.mocks';
 import { getApmConfig } from './get_apm_config';
 
 const defaultApmConfig = {
@@ -16,28 +16,28 @@ const defaultApmConfig = {
 
 describe('getApmConfig', () => {
   beforeEach(() => {
-    getConfigMock.mockReturnValue(defaultApmConfig);
+    getConfigurationMock.mockReturnValue(defaultApmConfig);
   });
 
   afterEach(() => {
-    getConfigMock.mockReset();
+    getConfigurationMock.mockReset();
     agentMock.currentTransaction = null;
   });
 
   it('returns null if apm is disabled', () => {
-    getConfigMock.mockReturnValue({
+    getConfigurationMock.mockReturnValue({
       active: false,
     });
     expect(getApmConfig('/path')).toBeNull();
 
-    getConfigMock.mockReturnValue(undefined);
+    getConfigurationMock.mockReturnValue(undefined);
     expect(getApmConfig('/path')).toBeNull();
   });
 
   it('calls `getConfig` with the correct parameters', () => {
     getApmConfig('/path');
 
-    expect(getConfigMock).toHaveBeenCalledWith('kibana-frontend');
+    expect(getConfigurationMock).toHaveBeenCalledWith('kibana-frontend');
   });
 
   it('returns the configuration from the `getConfig` call', () => {

src/core/server/http_resources/get_apm_config.ts

@@ -7,11 +7,10 @@
  */
 
 import agent from 'elastic-apm-node';
-// @ts-expect-error apm module is a js file outside of core (need to split APM/rum configuration)
-import { getConfig } from '../../../apm';
+import { getConfiguration } from '@kbn/apm-config-loader';
 
 export const getApmConfig = (requestPath: string) => {
-  const baseConfig = getConfig('kibana-frontend');
+  const baseConfig = getConfiguration('kibana-frontend');
   if (!baseConfig?.active) {
     return null;
   }