[SSRC] Add client internals and tests

src/remote-config/remote-config-api-client-internal.ts

@@ -21,10 +21,16 @@ import { PrefixedFirebaseError } from '../utils/error';
 import * as utils from '../utils/index';
 import * as validator from '../utils/validator';
 import { deepCopy } from '../utils/deep-copy';
-import { ListVersionsOptions, ListVersionsResult, RemoteConfigTemplate } from './remote-config-api';
+import {
+  ListVersionsOptions,
+  ListVersionsResult,
+  RemoteConfigTemplate,
+  RemoteConfigServerTemplateData
+} from './remote-config-api';
 
 // Remote Config backend constants
-const FIREBASE_REMOTE_CONFIG_V1_API = 'https://firebaseremoteconfig.googleapis.com/v1';
+// Honors env param to enable URL override independent of binary change.
+const FIREBASE_REMOTE_CONFIG_URL_BASE = process.env.FIREBASE_REMOTE_CONFIG_URL_BASE || 'https://firebaseremoteconfig.googleapis.com';
 const FIREBASE_REMOTE_CONFIG_HEADERS = {
   'X-Firebase-Client': `fire-admin-node/${utils.getSdkVersion()}`,
   // There is a known issue in which the ETag is not properly returned in cases where the request
@@ -166,6 +172,24 @@ export class RemoteConfigApiClient {
       });
   }
 
+  public getServerTemplate(): Promise<RemoteConfigServerTemplateData> {
+    return this.getUrl()
+      .then((url) => {
+        const request: HttpRequestConfig = {
+          method: 'GET',
+          url: `${url}/templates/server`,
+          headers: FIREBASE_REMOTE_CONFIG_HEADERS
+        };
+        return this.httpClient.send(request);
+      })
+      .then((resp) => {
+        return this.toRemoteConfigServerTemplate(resp);
+      })
+      .catch((err) => {
+        throw this.toFirebaseError(err);
+      });
+  }
+
   private sendPutRequest(template: RemoteConfigTemplate, etag: string, validateOnly?: boolean): Promise<HttpResponse> {
     let path = 'remoteConfig';
     if (validateOnly) {
@@ -191,7 +215,7 @@ export class RemoteConfigApiClient {
   private getUrl(): Promise<string> {
     return this.getProjectIdPrefix()
       .then((projectIdPrefix) => {
-        return `${FIREBASE_REMOTE_CONFIG_V1_API}/${projectIdPrefix}`;
+        return `${FIREBASE_REMOTE_CONFIG_URL_BASE}/v1/${projectIdPrefix}`;
       });
   }
 
@@ -255,6 +279,24 @@ export class RemoteConfigApiClient {
     };
   }
 
+  /**
+   * Creates a RemoteConfigServerTemplate from the API response.
+   * If provided, customEtag is used instead of the etag returned in the API response.
+   *
+   * @param {HttpResponse} resp API response object.
+   * @param {string} customEtag A custom etag to replace the etag fom the API response (Optional).
+   */
+  private toRemoteConfigServerTemplate(resp: HttpResponse, customEtag?: string): RemoteConfigServerTemplateData {
+    const etag = (typeof customEtag === 'undefined') ? resp.headers['etag'] : customEtag;
+    this.validateEtag(etag);
+    return {
+      conditions: resp.data.conditions,
+      parameters: resp.data.parameters,
+      etag,
+      version: resp.data.version,
+    };
+  }
+
   /**
    * Checks if the given RemoteConfigTemplate object is valid.
    * The object must have valid parameters, parameter groups, conditions, and an etag.

test/unit/remote-config/remote-config-api-client.spec.ts

@@ -33,6 +33,7 @@ import { getSdkVersion } from '../../../src/utils/index';
 import {
   RemoteConfigTemplate, Version, ListVersionsResult,
 } from '../../../src/remote-config/index';
+import { RemoteConfigServerTemplateData } from '../../../src/remote-config/remote-config-api';
 
 const expect = chai.expect;
 
@@ -661,6 +662,36 @@ describe('RemoteConfigApiClient', () => {
     });
   });
 
+  describe('getServerTemplate', () => {
+    it('should reject when project id is not available', () => {
+      return clientWithoutProjectId.getServerTemplate()
+        .should.eventually.be.rejectedWith(noProjectId);
+    });
+
+    // // tests for api response validations
+    runEtagHeaderTests(() => apiClient.getServerTemplate());
+    runErrorResponseTests(() => apiClient.getServerTemplate());
+
+    it('should resolve with the latest template on success', () => {
+      const stub = sinon
+        .stub(HttpClient.prototype, 'send')
+        .resolves(utils.responseFrom(TEST_RESPONSE, 200, { etag: 'etag-123456789012-1' }));
+      stubs.push(stub);
+      return apiClient.getServerTemplate()
+        .then((resp) => {
+          expect(resp.conditions).to.deep.equal(TEST_RESPONSE.conditions);
+          expect(resp.parameters).to.deep.equal(TEST_RESPONSE.parameters);
+          expect(resp.etag).to.equal('etag-123456789012-1');
+          expect(resp.version).to.deep.equal(TEST_RESPONSE.version);
+          expect(stub).to.have.been.calledOnce.and.calledWith({
+            method: 'GET',
+            url: 'https://firebaseremoteconfig.googleapis.com/v1/projects/test-project/templates/server',
+            headers: EXPECTED_HEADERS,
+          });
+        });
+    });
+  });
+
   function runTemplateVersionNumberTests(rcOperation: (v: string | number) => any): void {
     ['', null, NaN, true, [], {}].forEach((invalidVersion) => {
       it(`should reject if the versionNumber is: ${invalidVersion}`, () => {
@@ -677,7 +708,7 @@ describe('RemoteConfigApiClient', () => {
     });
   }
 
-  function runEtagHeaderTests(rcOperation: () => Promise<RemoteConfigTemplate>): void {
+  function runEtagHeaderTests(rcOperation: () => Promise<RemoteConfigTemplate | RemoteConfigServerTemplateData>): void {
     it('should reject when the etag is not present in the response', () => {
       const stub = sinon
         .stub(HttpClient.prototype, 'send')
@@ -690,7 +721,8 @@ describe('RemoteConfigApiClient', () => {
     });
   }
 
-  function runErrorResponseTests(rcOperation: () => Promise<RemoteConfigTemplate | ListVersionsResult>): void {
+  function runErrorResponseTests(
+    rcOperation: () => Promise<RemoteConfigTemplate | RemoteConfigServerTemplateData | ListVersionsResult>): void {
     it('should reject when a full platform error response is received', () => {
       const stub = sinon
         .stub(HttpClient.prototype, 'send')