linter better tests

Signed-off-by: d068544 <[email protected]>

samples/resilience-examples/.prettierrc

@@ -0,0 +1,8 @@
+{
+  "$schema": "http://json.schemastore.org/prettierrc",
+  "singleQuote": true,
+  "filepath": "*.ts",
+  "trailingComma": "none",
+  "arrowParens": "avoid",
+  "endOfLine": "lf"
+}

samples/resilience-examples/README.md

@@ -0,0 +1,12 @@
+# SAP Cloud SDK for JS Resilience examples
+
+## Description
+
+This folder contains a few simples examples about resilience and the SDK.
+The examples are using well established libraries and are tested for you.
+They are meant as a blueprint to illustrate how resilience can be achieved, but there are many other ways out there which could be more fitting in your use case.
+
+- In `src/circuit-breaker.ts` the opossum circuit breaker is wrapped around a request.
+- In `src/retry.ts` the async-retry wrapper is used to retry failed requests.
+
+There is always a `*.spec.ts` file next to the examples which shows the actual execution and that the libraries show the expected behaviour.

samples/resilience-examples/package.json

@@ -6,7 +6,8 @@
   "private": true,
   "license": "UNLICENSED",
   "scripts": {
-    "lint": "eslint \"src/**/*.ts\" --fix",
+    "lint": "eslint \"src/**/*.ts\" && yarn prettier .",
+    "lint:fix": "eslint \"src/**/*.ts\" --fix && yarn prettier . -w",
     "test": "jest"
   },
   "dependencies": {

samples/resilience-examples/src/circuit-breaker.spec.ts

@@ -4,41 +4,53 @@ import { createLogger } from '@sap-cloud-sdk/util';
 import { getAllBusinessPartnerWithCircuitBreaker } from './circuit-breaker';
 import { mockDestination, mockGetAllRequest } from './test-util';
 
-describe('circuit-breaker',()=>{
-    const numberWorkingRequests = [1,2,3,4,5];
-
-    const logger = createLogger('circuit-breaker');
-
-    beforeAll(()=>{
-        mockDestination();
-    });
-
-    beforeEach(()=>{
-        mockGetAllRequest(numberWorkingRequests.length);
-    });
-
-    afterEach(()=>{
-       nock.cleanAll();
-    });
-
-    afterAll(()=>{
-        unmockAllTestDestinations();
-    });
-
-    it('does not open the cuircuit breaker for no failed requests.',async ()=>{
-        const spy = jest.spyOn(logger,'warn');
-        await  Promise.all(numberWorkingRequests.map(()=>getAllBusinessPartnerWithCircuitBreaker(1)));
-        expect(spy).toHaveBeenCalledTimes(0);
-    });
-
-    it('opens the cuircuit after a few failed requests',async ()=>{
-        const spy = jest.spyOn(logger,'warn');
-
-        // The circuit breaker was configured to have 80% failure threshold. So 1 / 6 requests failing is enough to open the circuit
-        await  Promise.all([...numberWorkingRequests,6].map(()=>getAllBusinessPartnerWithCircuitBreaker(1)));
-        expect(spy).toHaveBeenCalledWith('Request failed to many times. Circuit breaker is open.');
-
-        // Circuit breaker is now open and the request is not executed.
-        await expect(getAllBusinessPartnerWithCircuitBreaker(1)).resolves.not.toThrow();
-    });
+describe('circuit-breaker', () => {
+  const numberWorkingRequests = [1, 2, 3, 4, 5];
+
+  const logger = createLogger('circuit-breaker');
+
+  beforeAll(() => {
+    mockDestination();
+  });
+
+  beforeEach(() => {
+    mockGetAllRequest(numberWorkingRequests.length);
+  });
+
+  afterEach(() => {
+    nock.cleanAll();
+  });
+
+  afterAll(() => {
+    unmockAllTestDestinations();
+  });
+
+  it('does not open the cuircuit breaker for no failed requests.', async () => {
+    const spy = jest.spyOn(logger, 'warn');
+    await Promise.all(
+      numberWorkingRequests.map(() =>
+        getAllBusinessPartnerWithCircuitBreaker(1)
+      )
+    );
+    expect(spy).toHaveBeenCalledTimes(0);
+  });
+
+  it('opens the cuircuit after a few failed requests', async () => {
+    const spy = jest.spyOn(logger, 'warn');
+
+    // The circuit breaker was configured to have 80% failure threshold. So 1 / 6 requests failing is enough to open the circuit
+    await Promise.all(
+      [...numberWorkingRequests, 6].map(() =>
+        getAllBusinessPartnerWithCircuitBreaker(1)
+      )
+    );
+    expect(spy).toHaveBeenCalledWith(
+      'Request failed to many times. Circuit breaker is open.'
+    );
+
+    // Circuit breaker is now open and the request is not executed.
+    await expect(
+      getAllBusinessPartnerWithCircuitBreaker(1)
+    ).resolves.not.toThrow();
+  });
 });

samples/resilience-examples/src/circuit-breaker.ts

@@ -1,27 +1,27 @@
-import { BusinessPartner, businessPartnerService } from '@sap/cloud-sdk-vdm-business-partner-service';
+import { BusinessPartner } from '@sap/cloud-sdk-vdm-business-partner-service';
 import CircuitBreaker from 'opossum';
 import { createLogger } from '@sap-cloud-sdk/util';
-import { destinationName } from './test-util';
+import { getAllBusinessPartner } from './test-util';
 
 const logger = createLogger('circuit-breaker');
 
-function getAllBusinessPartner(top: number): Promise<BusinessPartner[]>{
-    return businessPartnerService().businessPartnerApi.requestBuilder().getAll().top(top).execute({ destinationName });
-}
-
 const breakerOptions = {
-    timeout: 3000,
-    errorThresholdPercentage: 80,
-    resetTimeout: 30000
+  timeout: 3000,
+  errorThresholdPercentage: 80,
+  resetTimeout: 30000
 };
 
-// Create a new circuit breaker around the asyn method
-const breaker = new CircuitBreaker(getAllBusinessPartner,breakerOptions);
+// Create a new circuit breaker around the async method
+const breaker = new CircuitBreaker(getAllBusinessPartner, breakerOptions);
 
-// In the fallback you can put some logic to be executed if one system is not available.
-breaker.fallback(()=>logger.warn('Request failed to many times. Circuit breaker is open.'));
+// In the fallback you can put some logic to be executed if the breaker is open.
+breaker.fallback(() =>
+  logger.warn('Request failed to many times. Circuit breaker is open.')
+);
 
-// Execute the asyn method passing arguments if needed
-export function getAllBusinessPartnerWithCircuitBreaker(top: number): Promise<BusinessPartner[]>{
-    return breaker.fire(top);
+// Execute the async method passing arguments if needed
+export async function getAllBusinessPartnerWithCircuitBreaker(
+  top: number
+): Promise<BusinessPartner[]> {
+  return breaker.fire(top);
 }

samples/resilience-examples/src/retry.spec.ts

@@ -1,37 +1,58 @@
 import { unmockAllTestDestinations } from '@sap-cloud-sdk/test-util';
 import nock from 'nock';
-import { getAllBusinessPartners, getAllBusinessPartnerWithRetry } from './retry';
-import { destinationUrl, mockDestination, mockGetAllRequest } from './test-util';
-
-describe('retry',()=>{
-    beforeAll(()=>{
-       mockDestination();
-    });
-
-    beforeEach(()=>{
-    nock(destinationUrl)
-        .get(/.*/)
-        .times(2)
-        .reply(500);
-
-     mockGetAllRequest(1);
-    });
-
-    afterEach(()=>{
-        nock.cleanAll();
-    });
-
-    afterAll(()=>{
-        unmockAllTestDestinations();
-    });
-
-    it('fails without the retry.',async ()=>{
-        await expect(getAllBusinessPartners(1)()).rejects.toThrowError(`get request to ${destinationUrl}/sap/opu/odata/sap/API_BUSINESS_PARTNER failed!`);
-    });
-
-    it('resolves with retry',async ()=>{
-        // The mock will return after two failed attempts
-        const actual = await getAllBusinessPartnerWithRetry(1);
-        expect(actual.length).toBe(1);
-    });
+import { createLogger } from '@sap-cloud-sdk/util';
+import { getAllBusinessPartnerWithRetry } from './retry';
+import {
+  destinationUrl,
+  getAllBusinessPartner,
+  mockDestination,
+  mockGetAllRequest
+} from './test-util';
+
+describe('retry', () => {
+  beforeAll(() => {
+    mockDestination();
+  });
+
+  beforeEach(() => {
+    nock(destinationUrl).get(/.*/).times(2).reply(500);
+
+    mockGetAllRequest(1);
+  });
+
+  afterEach(() => {
+    nock.cleanAll();
+  });
+
+  afterAll(() => {
+    unmockAllTestDestinations();
+  });
+
+  it('rejects without the retry.', async () => {
+    await expect(getAllBusinessPartner(1)).rejects.toThrowError(
+      `get request to ${destinationUrl}/sap/opu/odata/sap/API_BUSINESS_PARTNER failed!`
+    );
+  });
+
+  it('resolves with retry', async () => {
+    // The mock will return after two failed attempts
+    const actual = await getAllBusinessPartnerWithRetry(1);
+    expect(actual.length).toBe(1);
+  });
+
+  it('does not retry on 403 error', async () => {
+    nock.cleanAll();
+    nock(destinationUrl).get(/.*/).times(1).reply(401);
+
+    const logger = createLogger('retry');
+    const spy = jest.spyOn(logger, 'warn');
+    await expect(getAllBusinessPartnerWithRetry(1)).rejects.toThrowError(
+      `get request to ${destinationUrl}/sap/opu/odata/sap/API_BUSINESS_PARTNER failed!`
+    );
+
+    expect(spy).toHaveBeenCalledTimes(1);
+    expect(spy).toHaveBeenCalledWith(
+      'Request failed with status 401 - no retry necessary.'
+    );
+  });
 });

samples/resilience-examples/src/retry.ts

@@ -1,16 +1,31 @@
-import { BusinessPartner, businessPartnerService } from '@sap/cloud-sdk-vdm-business-partner-service';
+import { BusinessPartner } from '@sap/cloud-sdk-vdm-business-partner-service';
 import retry from 'async-retry';
-import { destinationName } from './test-util';
+import { createLogger } from '@sap-cloud-sdk/util';
+import { getAllBusinessPartner } from './test-util';
 
-export function getAllBusinessPartners(top: number): () => Promise<BusinessPartner[]>{
-    return ()=> businessPartnerService().businessPartnerApi.requestBuilder().getAll().top(top).execute({ destinationName });
-}
+const logger = createLogger('retry');
 
 const options = {
-    retries : 2,
-    minTimeout: 500
+  retries: 2,
+  minTimeout: 500
 };
 
-export function getAllBusinessPartnerWithRetry(top: number): Promise<BusinessPartner[]>{
-    return retry(getAllBusinessPartners(top),options);
+// Create a wrapper passing arguments
+export async function getAllBusinessPartnerWithRetry(
+  top: number
+): Promise<BusinessPartner[]> {
+  // Wrap the retry block around the async function.
+  return retry(async bail => {
+    try {
+      const bps = await getAllBusinessPartner(top);
+      return bps;
+    } catch (error) {
+      // Use the bail() method to stop the retries for some cases
+      if (error.cause.response.status === 401) {
+        logger.warn('Request failed with status 401 - no retry necessary.');
+        bail(error);
+      }
+      throw error;
+    }
+  }, options);
 }

samples/resilience-examples/src/test-util.ts

@@ -1,22 +1,33 @@
 import { setTestDestination } from '@sap-cloud-sdk/test-util';
 import nock from 'nock';
+import {
+  BusinessPartner,
+  businessPartnerService
+} from '@sap/cloud-sdk-vdm-business-partner-service';
 
 export const destinationName = 'MyDestination';
-export const destinationUrl ='http://some.url.com';
+export const destinationUrl = 'http://some.url.com';
 
-export function mockDestination(): void{
-    setTestDestination({ name: destinationName,url:destinationUrl });
+export function mockDestination(): void {
+  setTestDestination({ name: destinationName, url: destinationUrl });
 }
 
 export const sampleResponse = {
-    d: {
-        results: [{ BusinessPartner:1234 }]
-    }
+  d: {
+    results: [{ BusinessPartner: 1234 }]
+  }
 };
 
-export function mockGetAllRequest(times: number): void{
-    nock(destinationUrl)
-        .get(/.*/)
-        .times(times)
-        .reply(200,sampleResponse);
+export function mockGetAllRequest(times: number): void {
+  nock(destinationUrl).get(/.*/).times(times).reply(200, sampleResponse);
+}
+
+export async function getAllBusinessPartner(
+  top: number
+): Promise<BusinessPartner[]> {
+  return businessPartnerService()
+    .businessPartnerApi.requestBuilder()
+    .getAll()
+    .top(top)
+    .execute({ destinationName });
 }

samples/resilience-examples/tsconfig.json

@@ -7,6 +7,7 @@
     "experimentalDecorators": true,
     "allowSyntheticDefaultImports": true,
     "moduleResolution": "node",
+    "lib": ["ES2017"],
     "esModuleInterop": true,
     "target": "es2017",
     "sourceMap": true,