FAI-9951: Add copy method to FarosClient (#237)

src/client.ts

@@ -41,9 +41,9 @@ export class FarosClient {
   readonly visibility?: string;
 
   constructor(
-    cfg: FarosClientConfig,
+    private readonly cfg: FarosClientConfig,
     readonly logger: Logger<string> = pino({name: 'faros-client'}),
-    axiosConfig: AxiosRequestConfig = DEFAULT_AXIOS_CONFIG
+    private readonly axiosConfig: AxiosRequestConfig = DEFAULT_AXIOS_CONFIG
   ) {
     const url = Utils.urlWithoutTrailingSlashes(cfg.url);
 
@@ -69,6 +69,24 @@ export class FarosClient {
     this.visibility = cfg.visibility;
   }
 
+  copy(
+    cfg?: Partial<FarosClientConfig>,
+    logger?: Logger<string>,
+    axiosConfig?: AxiosRequestConfig
+  ): FarosClient {
+    return new FarosClient(
+      {
+        ...this.cfg,
+        ...cfg,
+      },
+      logger ?? this.logger,
+      {
+        ...this.axiosConfig,
+        ...axiosConfig
+      }
+    );
+  }
+
   async tenant(): Promise<string> {
     try {
       const {data} = await this.api.get('/users/me');

test/client.test.ts

@@ -267,6 +267,47 @@ describe('client', () => {
     expect(res).toEqual({result: 'ok'});
   });
 
+  test('clone', async () => {
+    async function test(client: FarosClient, params: URLSearchParams) {
+      const mock = nock(apiUrl)
+        .post(
+          '/graphs/g1/graphql',
+          JSON.stringify({query: '{ tms_Task { uid } }'})
+        )
+        .query(params)
+        .reply(200, {data: {result: 'ok'}});
+      const res = await client.gql('g1', '{ tms_Task { uid } }');
+      mock.done();
+      expect(res).toEqual({result: 'ok'});
+    }
+    const clientConfig = {
+      url: apiUrl,
+      apiKey: 'test-key',
+      useGraphQLV2: true,
+    };
+    const client = new FarosClient(clientConfig);
+    // baseline test
+    await test(
+      client,
+      new URLSearchParams({phantoms: Phantom.IncludeNestedOnly}),
+    );
+    // test clone w/ different params
+    await test(
+      client.copy({phantoms: Phantom.Exclude}),
+      new URLSearchParams({phantoms: Phantom.Exclude}),
+    );
+    // test clone with no changes
+    await test(
+      client.copy(),
+      new URLSearchParams({phantoms: Phantom.IncludeNestedOnly}),
+    );
+    // test client again to ensure it wasn't changed
+    await test(
+      client,
+      new URLSearchParams({phantoms: Phantom.IncludeNestedOnly}),
+    );
+  });
+
   test('gql with variables', async () => {
     const query = `{
       query ($pageSize: Int = 10, $after: Cursor) {