[Backport 2.x] [MD] Support legacy client for data source (#2204)

src/core/server/http/router/router.ts

@@ -306,7 +306,6 @@ export class Router implements IRouter {
           opensearchDashboardsResponseFactory.badRequest({ body: e.message })
         );
       }
-      // TODO: add legacy data source client config error handling
 
       return hapiResponseAdapter.toInternalError();
     }

src/plugins/data/server/index_patterns/fetcher/index_patterns_fetcher.ts

@@ -28,7 +28,7 @@
  * under the License.
  */
 
-import { LegacyAPICaller, OpenSearchClient } from 'opensearch-dashboards/server';
+import { LegacyAPICaller } from 'opensearch-dashboards/server';
 
 import { getFieldCapabilities, resolveTimePattern, createNoMatchingIndicesError } from './lib';
 
@@ -48,9 +48,9 @@ interface FieldSubType {
 }
 
 export class IndexPatternsFetcher {
-  private _callDataCluster: LegacyAPICaller | OpenSearchClient;
+  private _callDataCluster: LegacyAPICaller;
 
-  constructor(callDataCluster: LegacyAPICaller | OpenSearchClient) {
+  constructor(callDataCluster: LegacyAPICaller) {
     this._callDataCluster = callDataCluster;
   }
 

src/plugins/data/server/index_patterns/fetcher/lib/field_capabilities/field_capabilities.ts

@@ -30,7 +30,7 @@
 
 import { defaults, keyBy, sortBy } from 'lodash';
 
-import { LegacyAPICaller, OpenSearchClient } from 'opensearch-dashboards/server';
+import { LegacyAPICaller } from 'opensearch-dashboards/server';
 import { callFieldCapsApi } from '../opensearch_api';
 import { FieldCapsResponse, readFieldCapsResponse } from './field_caps_response';
 import { mergeOverrides } from './overrides';
@@ -47,7 +47,7 @@ import { FieldDescriptor } from '../../index_patterns_fetcher';
  *  @return {Promise<Array<FieldDescriptor>>}
  */
 export async function getFieldCapabilities(
-  callCluster: LegacyAPICaller | OpenSearchClient,
+  callCluster: LegacyAPICaller,
   indices: string | string[] = [],
   metaFields: string[] = [],
   fieldCapsOptions?: { allowNoIndices: boolean }

src/plugins/data/server/index_patterns/fetcher/lib/opensearch_api.ts

@@ -57,23 +57,10 @@ export interface IndexAliasResponse {
  *  @return {Promise<IndexAliasResponse>}
  */
 export async function callIndexAliasApi(
-  callCluster: LegacyAPICaller | OpenSearchClient,
+  callCluster: LegacyAPICaller,
   indices: string[] | string
 ): Promise<IndicesAliasResponse> {
   try {
-    // This approach of identify between OpenSearchClient vs LegacyAPICaller
-    // will be deprecated after support data client with legacy client
-    // https://github.com/opensearch-project/OpenSearch-Dashboards/issues/2133
-    if ('transport' in callCluster) {
-      return (
-        await callCluster.indices.getAlias({
-          index: indices,
-          ignore_unavailable: true,
-          allow_no_indices: true,
-        })
-      ).body as IndicesAliasResponse;
-    }
-
     return (await callCluster('indices.getAlias', {
       index: indices,
       ignoreUnavailable: true,
@@ -97,25 +84,11 @@ export async function callIndexAliasApi(
  *  @return {Promise<FieldCapsResponse>}
  */
 export async function callFieldCapsApi(
-  callCluster: LegacyAPICaller | OpenSearchClient,
+  callCluster: LegacyAPICaller,
   indices: string[] | string,
   fieldCapsOptions: { allowNoIndices: boolean } = { allowNoIndices: false }
 ) {
   try {
-    // This approach of identify between OpenSearchClient vs LegacyAPICaller
-    // will be deprecated after support data client with legacy client
-    // https://github.com/opensearch-project/OpenSearch-Dashboards/issues/2133
-    if ('transport' in callCluster) {
-      return (
-        await callCluster.fieldCaps({
-          index: indices,
-          fields: '*',
-          ignore_unavailable: true,
-          allow_no_indices: fieldCapsOptions.allowNoIndices,
-        })
-      ).body as FieldCapsResponse;
-    }
-
     return (await callCluster('fieldCaps', {
       index: indices,
       fields: '*',

src/plugins/data/server/index_patterns/fetcher/lib/resolve_time_pattern.ts

@@ -47,10 +47,7 @@ import { callIndexAliasApi, IndicesAliasResponse } from './opensearch_api';
  *                            and the indices that actually match the time
  *                            pattern (matches);
  */
-export async function resolveTimePattern(
-  callCluster: LegacyAPICaller | OpenSearchClient,
-  timePattern: string
-) {
+export async function resolveTimePattern(callCluster: LegacyAPICaller, timePattern: string) {
   const aliases = await callIndexAliasApi(callCluster, timePatternToWildcard(timePattern));
 
   const allIndexDetails = chain<IndicesAliasResponse>(aliases)

src/plugins/data/server/index_patterns/routes.ts

@@ -29,7 +29,11 @@
  */
 
 import { schema } from '@osd/config-schema';
-import { HttpServiceSetup, RequestHandlerContext } from 'opensearch-dashboards/server';
+import {
+  HttpServiceSetup,
+  LegacyAPICaller,
+  RequestHandlerContext,
+} from 'opensearch-dashboards/server';
 import { IndexPatternsFetcher } from './fetcher';
 
 export function registerRoutes(http: HttpServiceSetup) {
@@ -151,11 +155,12 @@ export function registerRoutes(http: HttpServiceSetup) {
   );
 }
 
-const decideClient = async (context: RequestHandlerContext, request: any) => {
+const decideClient = async (
+  context: RequestHandlerContext,
+  request: any
+): Promise<LegacyAPICaller> => {
   const dataSourceId = request.query.data_source;
-  if (dataSourceId) {
-    return await context.dataSource.opensearch.getClient(dataSourceId);
-  }
-
-  return context.core.opensearch.legacy.client.callAsCurrentUser;
+  return dataSourceId
+    ? (context.dataSource.opensearch.legacy.getClient(dataSourceId).callAPI as LegacyAPICaller)
+    : context.core.opensearch.legacy.client.callAsCurrentUser;
 };

src/plugins/data_source/server/client/client_pool.ts

@@ -4,31 +4,32 @@
  */
 
 import { Client } from '@opensearch-project/opensearch';
+import { Client as LegacyClient } from 'elasticsearch';
 import LRUCache from 'lru-cache';
 import { Logger } from 'src/core/server';
 import { DataSourcePluginConfigType } from '../../config';
 
 export interface OpenSearchClientPoolSetup {
-  getClientFromPool: (id: string) => Client | undefined;
-  addClientToPool: (endpoint: string, client: Client) => void;
+  getClientFromPool: (id: string) => Client | LegacyClient | undefined;
+  addClientToPool: (endpoint: string, client: Client | LegacyClient) => void;
 }
 
 /**
- * OpenSearch client pool.
+ * OpenSearch client pool for data source.
  *
  * This client pool uses an LRU cache to manage OpenSearch Js client objects.
  * It reuse TPC connections for each OpenSearch endpoint.
  */
 export class OpenSearchClientPool {
   // LRU cache
-  //   key: data source endpoint url
-  //   value: OpenSearch client object
-  private cache?: LRUCache<string, Client>;
+  //   key: data source endpoint
+  //   value: OpenSearch client object | Legacy client object
+  private cache?: LRUCache<string, Client | LegacyClient>;
   private isClosed = false;
 
   constructor(private logger: Logger) {}
 
-  public async setup(config: DataSourcePluginConfigType) {
+  public async setup(config: DataSourcePluginConfigType): Promise<OpenSearchClientPoolSetup> {
     const logger = this.logger;
     const { size } = config.clientPool;
 
@@ -53,7 +54,7 @@ export class OpenSearchClientPool {
       return this.cache!.get(endpoint);
     };
 
-    const addClientToPool = (endpoint: string, client: Client) => {
+    const addClientToPool = (endpoint: string, client: Client | LegacyClient) => {
       this.cache!.set(endpoint, client);
     };
 

src/plugins/data_source/server/client/configure_client.test.ts

@@ -15,6 +15,7 @@ import { ClientOptions } from '@opensearch-project/opensearch';
 // eslint-disable-next-line @osd/eslint/no-restricted-paths
 import { opensearchClientMock } from '../../../../core/server/opensearch/client/mocks';
 import { CryptographyClient } from '../cryptography';
+import { DataSourceClientParams } from '../types';
 
 const DATA_SOURCE_ID = 'a54b76ec86771ee865a0f74a305dfff8';
 const cryptoClient = new CryptographyClient('test', 'test', new Array(32).fill(0));
@@ -28,6 +29,7 @@ describe('configureClient', () => {
   let clientOptions: ClientOptions;
   let dataSourceAttr: DataSourceAttributes;
   let dsClient: ReturnType<typeof opensearchClientMock.createInternalClient>;
+  let dataSourceClientParams: DataSourceClientParams;
 
   beforeEach(() => {
     dsClient = opensearchClientMock.createInternalClient();
@@ -70,9 +72,13 @@ describe('configureClient', () => {
       references: [],
     });
 
-    ClientMock.mockImplementation(() => {
-      return dsClient;
-    });
+    dataSourceClientParams = {
+      dataSourceId: DATA_SOURCE_ID,
+      savedObjects: savedObjectsMock,
+      cryptographyClient: cryptoClient,
+    };
+
+    ClientMock.mockImplementation(() => dsClient);
   });
 
   afterEach(() => {
@@ -94,14 +100,7 @@ describe('configureClient', () => {
 
     parseClientOptionsMock.mockReturnValue(clientOptions);
 
-    const client = await configureClient(
-      DATA_SOURCE_ID,
-      savedObjectsMock,
-      cryptoClient,
-      clientPoolSetup,
-      config,
-      logger
-    );
+    const client = await configureClient(dataSourceClientParams, clientPoolSetup, config, logger);
 
     expect(parseClientOptionsMock).toHaveBeenCalled();
     expect(ClientMock).toHaveBeenCalledTimes(1);
@@ -113,14 +112,7 @@ describe('configureClient', () => {
   test('configure client with auth.type == username_password, will first call decrypt()', async () => {
     const spy = jest.spyOn(cryptoClient, 'decodeAndDecrypt').mockResolvedValue('password');
 
-    const client = await configureClient(
-      DATA_SOURCE_ID,
-      savedObjectsMock,
-      cryptoClient,
-      clientPoolSetup,
-      config,
-      logger
-    );
+    const client = await configureClient(dataSourceClientParams, clientPoolSetup, config, logger);
 
     expect(ClientMock).toHaveBeenCalledTimes(1);
     expect(savedObjectsMock.get).toHaveBeenCalledTimes(1);

src/plugins/data_source/server/client/configure_client.ts

@@ -14,13 +14,12 @@ import {
 import { DataSourcePluginConfigType } from '../../config';
 import { CryptographyClient } from '../cryptography';
 import { DataSourceConfigError } from '../lib/error';
+import { DataSourceClientParams } from '../types';
 import { parseClientOptions } from './client_config';
 import { OpenSearchClientPoolSetup } from './client_pool';
 
 export const configureClient = async (
-  dataSourceId: string,
-  savedObjects: SavedObjectsClientContract,
-  cryptographyClient: CryptographyClient,
+  { dataSourceId, savedObjects, cryptographyClient }: DataSourceClientParams,
   openSearchClientPoolSetup: OpenSearchClientPoolSetup,
   config: DataSourcePluginConfigType,
   logger: Logger
@@ -68,20 +67,26 @@ export const getCredential = async (
  *
  * @param rootClient root client for the connection with given data source endpoint.
  * @param dataSource data source saved object
- * @param cryptographyClient cryptography client for password encryption / decrpytion
+ * @param cryptographyClient cryptography client for password encryption / decryption
  * @returns child client.
  */
 const getQueryClient = async (
   rootClient: Client,
   dataSource: SavedObject<DataSourceAttributes>,
   cryptographyClient: CryptographyClient
 ): Promise<Client> => {
-  if (AuthType.NoAuth === dataSource.attributes.auth.type) {
-    return rootClient.child();
-  } else {
-    const credential = await getCredential(dataSource, cryptographyClient);
+  const authType = dataSource.attributes.auth.type;
+
+  switch (authType) {
+    case AuthType.NoAuth:
+      return rootClient.child();
+
+    case AuthType.UsernamePasswordType:
+      const credential = await getCredential(dataSource, cryptographyClient);
+      return getBasicAuthClient(rootClient, credential);
 
-    return getBasicAuthClient(rootClient, credential);
+    default:
+      throw Error(`${authType} is not a supported auth type for data source`);
   }
 };
 
@@ -101,7 +106,7 @@ const getRootClient = (
   const endpoint = dataSourceAttr.endpoint;
   const cachedClient = getClientFromPool(endpoint);
   if (cachedClient) {
-    return cachedClient;
+    return cachedClient as Client;
   } else {
     const clientOptions = parseClientOptions(config, endpoint);
 

src/plugins/data_source/server/client/index.ts

@@ -3,5 +3,5 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-export { OpenSearchClientPool } from './client_pool';
-export { configureClient } from './configure_client';
+export { OpenSearchClientPool, OpenSearchClientPoolSetup } from './client_pool';
+export { configureClient, getDataSource, getCredential } from './configure_client';

src/plugins/data_source/server/data_source_service.test.ts

@@ -33,6 +33,7 @@ describe('Data Source Service', () => {
     test('exposes proper contract', async () => {
       const setup = await service.setup(config);
       expect(setup).toHaveProperty('getDataSourceClient');
+      expect(setup).toHaveProperty('getDataSourceLegacyClient');
     });
   });
 });