Mm/prc 7963 client ex status code override (#58)

Release 5.4.0

CHANGELOG.md

@@ -4,11 +4,17 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 
+## [5.4.0] - 2024-02-08
+
+### Added
+
+HttpClient options now accept `clientExceptionStatusCodeMapOverride` which can be used to override the default HTTP error status code mapping. This is useful e.g. when a dependent service is not following REST-ful best practices and e.g. returns a 403 when there's an intermittent network error communicating with the authorization service
+
 ## [5.3.2] - 2024-02-08
 
 ### Fixed
 
-Error details of external HTTP error resposes are propagated correctly
+Error details of external HTTP error responses are propagated correctly
 
 ## [5.3.1] - 2023-10-25
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "lambda-essentials-ts",
-  "version": "5.3.2",
+  "version": "5.4.0",
   "description": "A selection of the finest modules supporting authorization, API routing, error handling, logging and sending HTTP requests.",
   "main": "lib/index.js",
   "private": false,

src/exceptions/clientException.ts

@@ -13,21 +13,33 @@ export class ClientException extends Exception {
     422: 422,
   };
 
-  constructor(serviceName: string, originalStatusCode?: number, details?: any) {
+  constructor(
+    serviceName: string,
+    originalStatusCode?: number,
+    details?: any,
+    statusCodeMapOverride?: Record<number, number>,
+  ) {
     super(
       `Dependent service "${serviceName}" returned error`,
-      ClientException.convertStatusCode(originalStatusCode),
+      ClientException.convertStatusCode(originalStatusCode, statusCodeMapOverride),
       details,
     );
     this.serviceName = serviceName;
     this.originalStatusCode = originalStatusCode;
   }
 
-  private static convertStatusCode(originalStatusCode?: number) {
+  private static convertStatusCode(
+    originalStatusCode?: number,
+    statusCodeMapOverride?: Record<number, number>,
+  ) {
     let statusCode = 503;
+    const statusCodeMap = {
+      ...ClientException.statusCodeMap,
+      ...(statusCodeMapOverride || {}),
+    };
 
-    if (originalStatusCode && this.statusCodeMap[originalStatusCode]) {
-      statusCode = this.statusCodeMap[originalStatusCode];
+    if (originalStatusCode && statusCodeMap[originalStatusCode]) {
+      statusCode = statusCodeMap[originalStatusCode];
     }
 
     return statusCode;

src/httpClient/httpClient.ts

@@ -43,7 +43,9 @@ export default class HttpClient {
   private readonly enableCache: boolean;
 
   private readonly timeout?: number;
-
+
+  private readonly clientExceptionStatusCodeMapOverride?: Record<number, number>;
+
   /**
    * Create a new Instance of the HttpClient
    */
@@ -57,6 +59,7 @@ export default class HttpClient {
     this.enableCache = options?.enableCache ?? false;
     this.enableRetry = options?.enableRetry ?? false;
     this.timeout = options?.timeout;
+    this.clientExceptionStatusCodeMapOverride = options?.clientExceptionStatusCodeMapOverride;
     this.client =
       options?.client ??
       axios.create({
@@ -103,7 +106,7 @@ export default class HttpClient {
     if (this.timeout) {
       this.client.defaults.timeout = this.timeout;
     }
-    
+
     this.client.interceptors.request.use(
       (config) => {
         if (this.logOptions.enabledLogs.includes(HttpLogType.requests)) {
@@ -135,6 +138,7 @@ export default class HttpClient {
           hostname,
           serializedAxiosError?.status,
           serializedAxiosError?.details,
+          this.clientExceptionStatusCodeMapOverride,
         );
       },
     );
@@ -183,6 +187,7 @@ export default class HttpClient {
           hostname,
           serializedAxiosError?.status,
           serializedAxiosError?.details,
+          this.clientExceptionStatusCodeMapOverride,
         );
       },
     );
@@ -360,6 +365,11 @@ export interface HttpClientOptions {
    * @link https://github.com/axios/axios/blob/main/README.md#request-config
    */
   timeout?: number;
+  /**
+   * Override the default mapping of status code when wrapping error responses returned by dependencies into ClientException.
+   * This is useful, when dependent services return incorrect status codes than then drive incorrect behavior upstream (e.g. 403 instead of 503)
+   */
+  clientExceptionStatusCodeMapOverride?: Record<number, number>;
 }
 
 /**

tests/exceptions/clientException.test.ts

@@ -7,9 +7,9 @@ interface AxiosErrorTestData {
 }
 
 describe('ClientException', () => {
-  describe('converts Axios errors', () => {
-    const testServiceName = 'test-service-name';
+  const testServiceName = 'test-service-name';
 
+  describe('converts Axios errors', () => {
     const createError = (status: number): SerializedAxiosError => ({
       status,
       details: [],
@@ -53,4 +53,31 @@ describe('ClientException', () => {
       }),
     );
   });
+
+  describe('clientExceptionStatusCodeMapOverride', () => {
+    test('overrides default client exception status code mapping with clientExceptionStatusCodeMapOverride', async () => {
+      const expectedStatusCode = 503;
+      const originalStatusCode = 403;
+      const axiosError: SerializedAxiosError = {
+        status: originalStatusCode,
+        details: [],
+      };
+      const clientExceptionStatusCodeMapOverride = {
+        403: 503,
+      };
+
+      const clientException = new ClientException(
+        testServiceName,
+        axiosError.status,
+        axiosError,
+        clientExceptionStatusCodeMapOverride,
+      );
+
+      expect(clientException.message).toEqual(
+        `Dependent service "${testServiceName}" returned error`,
+      );
+      expect(clientException.originalStatusCode).toEqual(originalStatusCode);
+      expect(clientException.statusCode).toEqual(expectedStatusCode);
+    });
+  });
 });