feat(slo): Introduce createSLO application service (#140523)

x-pack/plugins/observability/server/routes/slo/route.ts

@@ -5,20 +5,26 @@
  * 2.0.
  */
 
-import uuid from 'uuid';
 import {
+  CreateSLO,
+  DefaultResourceInstaller,
+  DefaultTransformInstaller,
   KibanaSavedObjectsSLORepository,
-  ResourceInstaller,
-  TransformInstaller,
 } from '../../services/slo';
 import {
   ApmTransactionDurationTransformGenerator,
   ApmTransactionErrorRateTransformGenerator,
+  TransformGenerator,
 } from '../../services/slo/transform_generators';
-import { SLO } from '../../types/models';
+import { SLITypes } from '../../types/models';
 import { createSLOParamsSchema } from '../../types/schema';
 import { createObservabilityServerRoute } from '../create_observability_server_route';
 
+const transformGenerators: Record<SLITypes, TransformGenerator> = {
+  'slo.apm.transaction_duration': new ApmTransactionDurationTransformGenerator(),
+  'slo.apm.transaction_error_rate': new ApmTransactionErrorRateTransformGenerator(),
+};
+
 const createSLORoute = createObservabilityServerRoute({
   endpoint: 'POST /api/observability/slos',
   options: {
@@ -30,31 +36,14 @@ const createSLORoute = createObservabilityServerRoute({
     const soClient = (await context.core).savedObjects.client;
     const spaceId = spacesService.getSpaceId(request);
 
-    const resourceInstaller = new ResourceInstaller(esClient, logger);
+    const resourceInstaller = new DefaultResourceInstaller(esClient, logger);
     const repository = new KibanaSavedObjectsSLORepository(soClient);
-    const transformInstaller = new TransformInstaller(
-      {
-        'slo.apm.transaction_duration': new ApmTransactionDurationTransformGenerator(),
-        'slo.apm.transaction_error_rate': new ApmTransactionErrorRateTransformGenerator(),
-      },
-      esClient,
-      logger
-    );
-
-    await resourceInstaller.ensureCommonResourcesInstalled(spaceId);
-
-    const slo: SLO = {
-      ...params.body,
-      id: uuid.v1(),
-      settings: {
-        destination_index: params.body.settings?.destination_index,
-      },
-    };
+    const transformInstaller = new DefaultTransformInstaller(transformGenerators, esClient, logger);
+    const createSLO = new CreateSLO(resourceInstaller, repository, transformInstaller, spaceId);
 
-    await repository.save(slo);
-    await transformInstaller.installAndStartTransform(slo, spaceId);
+    const response = await createSLO.execute(params.body);
 
-    return slo;
+    return response;
   },
 });
 

x-pack/plugins/observability/server/services/slo/create_slo.test.ts

@@ -0,0 +1,67 @@
+/*
+ * 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; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import { CreateSLO } from './create_slo';
+import { createAPMTransactionErrorRateIndicator, createSLOParams } from './fixtures/slo';
+import {
+  createResourceInstallerMock,
+  createSLORepositoryMock,
+  createTransformInstallerMock,
+} from './mocks';
+import { ResourceInstaller } from './resource_installer';
+import { SLORepository } from './slo_repository';
+import { TransformInstaller } from './transform_installer';
+
+const SPACE_ID = 'some-space-id';
+
+describe('createSLO', () => {
+  let mockResourceInstaller: jest.Mocked<ResourceInstaller>;
+  let mockRepository: jest.Mocked<SLORepository>;
+  let mockTransformInstaller: jest.Mocked<TransformInstaller>;
+  let createSLO: CreateSLO;
+
+  beforeEach(() => {
+    mockResourceInstaller = createResourceInstallerMock();
+    mockRepository = createSLORepositoryMock();
+    mockTransformInstaller = createTransformInstallerMock();
+    createSLO = new CreateSLO(
+      mockResourceInstaller,
+      mockRepository,
+      mockTransformInstaller,
+      SPACE_ID
+    );
+  });
+
+  describe('happy path', () => {
+    it('calls the expected services', async () => {
+      const sloParams = createSLOParams(createAPMTransactionErrorRateIndicator());
+      const response = await createSLO.execute(sloParams);
+
+      expect(mockResourceInstaller.ensureCommonResourcesInstalled).toHaveBeenCalledWith(SPACE_ID);
+      expect(mockRepository.save).toHaveBeenCalledWith(
+        expect.objectContaining({ ...sloParams, id: expect.any(String) })
+      );
+      expect(mockTransformInstaller.installAndStartTransform).toHaveBeenCalledWith(
+        expect.objectContaining({ ...sloParams, id: expect.any(String) }),
+        SPACE_ID
+      );
+      expect(response).toEqual(expect.objectContaining({ id: expect.any(String) }));
+    });
+  });
+
+  describe('unhappy path', () => {
+    it('deletes the SLO saved objects when transform installation fails', async () => {
+      mockTransformInstaller.installAndStartTransform.mockRejectedValue(
+        new Error('Transform Error')
+      );
+      const sloParams = createSLOParams(createAPMTransactionErrorRateIndicator());
+
+      await expect(createSLO.execute(sloParams)).rejects.toThrowError('Transform Error');
+      expect(mockRepository.deleteById).toBeCalled();
+    });
+  });
+});

x-pack/plugins/observability/server/services/slo/create_slo.ts

@@ -0,0 +1,56 @@
+/*
+ * 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; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import uuid from 'uuid';
+
+import { SLO } from '../../types/models';
+import { ResourceInstaller } from './resource_installer';
+import { SLORepository } from './slo_repository';
+import { TransformInstaller } from './transform_installer';
+
+import { CreateSLOParams, CreateSLOResponse } from '../../types/schema';
+
+export class CreateSLO {
+  constructor(
+    private resourceInstaller: ResourceInstaller,
+    private repository: SLORepository,
+    private transformInstaller: TransformInstaller,
+    private spaceId: string
+  ) {}
+
+  public async execute(sloParams: CreateSLOParams): Promise<CreateSLOResponse> {
+    const slo = this.toSLO(sloParams);
+
+    await this.resourceInstaller.ensureCommonResourcesInstalled(this.spaceId);
+    await this.repository.save(slo);
+
+    try {
+      await this.transformInstaller.installAndStartTransform(slo, this.spaceId);
+    } catch (err) {
+      await this.repository.deleteById(slo.id);
+      throw err;
+    }
+
+    return this.toResponse(slo);
+  }
+
+  private toSLO(sloParams: CreateSLOParams): SLO {
+    return {
+      ...sloParams,
+      id: uuid.v1(),
+      settings: {
+        destination_index: sloParams.settings?.destination_index,
+      },
+    };
+  }
+
+  private toResponse(slo: SLO): CreateSLOResponse {
+    return {
+      id: slo.id,
+    };
+  }
+}

x-pack/plugins/observability/server/services/slo/fixtures/slo.ts

@@ -7,12 +7,11 @@
 
 import uuid from 'uuid';
 import { SLI, SLO } from '../../../types/models';
+import { CreateSLOParams } from '../../../types/schema';
 
-export const createSLO = (indicator: SLI): SLO => ({
-  id: uuid.v1(),
+const commonSLO: Omit<CreateSLOParams, 'indicator'> = {
   name: 'irrelevant',
   description: 'irrelevant',
-  indicator,
   time_window: {
     duration: '7d',
     is_rolling: true,
@@ -21,9 +20,20 @@ export const createSLO = (indicator: SLI): SLO => ({
   objective: {
     target: 0.999,
   },
+};
+
+export const createSLOParams = (indicator: SLI): CreateSLOParams => ({
+  ...commonSLO,
+  indicator,
+});
+
+export const createSLO = (indicator: SLI): SLO => ({
+  ...commonSLO,
+  id: uuid.v1(),
   settings: {
     destination_index: 'some-index',
   },
+  indicator,
 });
 
 export const createAPMTransactionErrorRateIndicator = (params = {}): SLI => ({

x-pack/plugins/observability/server/services/slo/index.ts

@@ -8,3 +8,4 @@
 export * from './resource_installer';
 export * from './slo_repository';
 export * from './transform_installer';
+export * from './create_slo';

x-pack/plugins/observability/server/services/slo/mocks/index.ts

@@ -0,0 +1,32 @@
+/*
+ * 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; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import { ResourceInstaller } from '../resource_installer';
+import { SLORepository } from '../slo_repository';
+import { TransformInstaller } from '../transform_installer';
+
+const createResourceInstallerMock = (): jest.Mocked<ResourceInstaller> => {
+  return {
+    ensureCommonResourcesInstalled: jest.fn(),
+  };
+};
+
+const createTransformInstallerMock = (): jest.Mocked<TransformInstaller> => {
+  return {
+    installAndStartTransform: jest.fn(),
+  };
+};
+
+const createSLORepositoryMock = (): jest.Mocked<SLORepository> => {
+  return {
+    save: jest.fn(),
+    findById: jest.fn(),
+    deleteById: jest.fn(),
+  };
+};
+
+export { createResourceInstallerMock, createTransformInstallerMock, createSLORepositoryMock };

x-pack/plugins/observability/server/services/slo/resource_installer.test.ts

@@ -15,14 +15,14 @@ import {
   SLO_INGEST_PIPELINE_NAME,
   SLO_RESOURCES_VERSION,
 } from '../../assets/constants';
-import { ResourceInstaller } from './resource_installer';
+import { DefaultResourceInstaller } from './resource_installer';
 
 describe('resourceInstaller', () => {
   describe("when the common resources don't exist", () => {
     it('installs the common resources', async () => {
       const mockClusterClient = elasticsearchServiceMock.createElasticsearchClient();
       mockClusterClient.indices.existsIndexTemplate.mockResponseOnce(false);
-      const installer = new ResourceInstaller(mockClusterClient, loggerMock.create());
+      const installer = new DefaultResourceInstaller(mockClusterClient, loggerMock.create());
 
       await installer.ensureCommonResourcesInstalled();
 
@@ -51,7 +51,7 @@ describe('resourceInstaller', () => {
       mockClusterClient.ingest.getPipeline.mockResponseOnce({
         [SLO_INGEST_PIPELINE_NAME]: { _meta: { version: SLO_RESOURCES_VERSION } },
       } as IngestGetPipelineResponse);
-      const installer = new ResourceInstaller(mockClusterClient, loggerMock.create());
+      const installer = new DefaultResourceInstaller(mockClusterClient, loggerMock.create());
 
       await installer.ensureCommonResourcesInstalled();
 

x-pack/plugins/observability/server/services/slo/resource_installer.ts

@@ -24,7 +24,11 @@ import { getSLOSettingsTemplate } from '../../assets/component_templates/slo_set
 import { getSLOIndexTemplate } from '../../assets/index_templates/slo_index_templates';
 import { getSLOPipelineTemplate } from '../../assets/ingest_templates/slo_pipeline_template';
 
-export class ResourceInstaller {
+export interface ResourceInstaller {
+  ensureCommonResourcesInstalled(spaceId: string): Promise<void>;
+}
+
+export class DefaultResourceInstaller implements ResourceInstaller {
   constructor(private esClient: ElasticsearchClient, private logger: Logger) {}
 
   public async ensureCommonResourcesInstalled(spaceId: string = 'default'): Promise<void> {

x-pack/plugins/observability/server/services/slo/slo_repository.test.ts

@@ -38,7 +38,7 @@ function aStoredSLO(slo: SLO): SavedObject<StoredSLO> {
   };
 }
 
-describe('sloRepository', () => {
+describe('KibanaSavedObjectsSLORepository', () => {
   let soClientMock: jest.Mocked<SavedObjectsClientContract>;
 
   beforeEach(() => {
@@ -71,4 +71,12 @@ describe('sloRepository', () => {
     expect(foundSLO).toEqual(anSLO);
     expect(soClientMock.get).toHaveBeenCalledWith(SO_SLO_TYPE, anSLO.id);
   });
+
+  it('removes an SLO', async () => {
+    const repository = new KibanaSavedObjectsSLORepository(soClientMock);
+
+    await repository.deleteById(anSLO.id);
+
+    expect(soClientMock.delete).toHaveBeenCalledWith(SO_SLO_TYPE, anSLO.id);
+  });
 });

x-pack/plugins/observability/server/services/slo/slo_repository.ts

@@ -13,6 +13,7 @@ import { SO_SLO_TYPE } from '../../saved_objects';
 export interface SLORepository {
   save(slo: SLO): Promise<SLO>;
   findById(id: string): Promise<SLO>;
+  deleteById(id: string): Promise<void>;
 }
 
 export class KibanaSavedObjectsSLORepository implements SLORepository {
@@ -33,6 +34,10 @@ export class KibanaSavedObjectsSLORepository implements SLORepository {
     const slo = await this.soClient.get<StoredSLO>(SO_SLO_TYPE, id);
     return toSLOModel(slo.attributes);
   }
+
+  async deleteById(id: string): Promise<void> {
+    await this.soClient.delete(SO_SLO_TYPE, id);
+  }
 }
 
 function toSLOModel(slo: StoredSLO): SLO {

x-pack/plugins/observability/server/services/slo/transform_generators/apm_transaction_error_rate.ts

@@ -10,15 +10,15 @@ import {
   MappingRuntimeFieldType,
   TransformPutTransformRequest,
 } from '@elastic/elasticsearch/lib/api/types';
-import { getSLODestinationIndexName, SLO_INGEST_PIPELINE_NAME } from '../../../assets/constants';
 import { getSLOTransformTemplate } from '../../../assets/transform_templates/slo_transform_template';
+import { TransformGenerator } from '.';
+import { getSLODestinationIndexName, SLO_INGEST_PIPELINE_NAME } from '../../../assets/constants';
 import {
   apmTransactionErrorRateSLOSchema,
   APMTransactionErrorRateSLO,
   SLO,
 } from '../../../types/models';
 import { ALL_VALUE } from '../../../types/schema';
-import { TransformGenerator } from '.';
 
 const APM_SOURCE_INDEX = 'metrics-apm*';
 const ALLOWED_STATUS_CODES = ['2xx', '3xx', '4xx', '5xx'];