feat: cache results of getEnv() (#857)

googleapis · Dec 23, 2019 · d4545a9 · d4545a9
1 parent 1147733
commit d4545a9
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Showing 3 changed files with 44 additions and 15 deletions.
diff --git a/package.json b/package.json
@@ -21,7 +21,7 @@
  "base64-js": "^1.3.0",
  "fast-text-encoding": "^1.0.0",
  "gaxios": "^2.1.0",
- "gcp-metadata": "^3.2.0",
+ "gcp-metadata": "^3.3.0",
  "gtoken": "^4.1.0",
  "jws": "^3.1.5",
  "lru-cache": "^5.0.0"

diff --git a/src/auth/envDetect.ts b/src/auth/envDetect.ts
@@ -22,27 +22,34 @@ export enum GCPEnv {
  NONE = 'NONE',
 }
 
-let env: GCPEnv | undefined;
+let envPromise: Promise<GCPEnv> | undefined;
 
 export function clear() {
- env = undefined;
+ envPromise = undefined;
 }
 
 export async function getEnv() {
- if (!env) {
- if (isAppEngine()) {
- env = GCPEnv.APP_ENGINE;
- } else if (isCloudFunction()) {
- env = GCPEnv.CLOUD_FUNCTIONS;
- } else if (await isComputeEngine()) {
- if (await isKubernetesEngine()) {
- env = GCPEnv.KUBERNETES_ENGINE;
- } else {
- env = GCPEnv.COMPUTE_ENGINE;
- }
+ if (envPromise) {
+ return envPromise;
+ }
+ envPromise = getEnvMemoized();
+ return envPromise;
+}
+
+async function getEnvMemoized(): Promise<GCPEnv> {
+ let env = GCPEnv.NONE;
+ if (isAppEngine()) {
+ env = GCPEnv.APP_ENGINE;
+ } else if (isCloudFunction()) {
+ env = GCPEnv.CLOUD_FUNCTIONS;
+ } else if (await isComputeEngine()) {
+ if (await isKubernetesEngine()) {
+ env = GCPEnv.KUBERNETES_ENGINE;
  } else {
- env = GCPEnv.NONE;
+ env = GCPEnv.COMPUTE_ENGINE;
  }
+ } else {
+ env = GCPEnv.NONE;
  }
  return env;
 }

diff --git a/test/test.googleauth.ts b/test/test.googleauth.ts
@@ -22,6 +22,7 @@ import {
  HEADERS,
  HOST_ADDRESS,
  SECONDARY_HOST_ADDRESS,
+ resetIsAvailableCache,
 } from 'gcp-metadata';
 import * as nock from 'nock';
 import * as os from 'os';
@@ -80,6 +81,7 @@ describe('googleauth', () => {
  let createLinuxWellKnownStream: Function;
  let createWindowsWellKnownStream: Function;
  beforeEach(() => {
+ resetIsAvailableCache();
  auth = new GoogleAuth();
  exposeWindowsWellKnownFile = false;
  exposeLinuxWellKnownFile = false;
@@ -1294,6 +1296,26 @@ describe('googleauth', () => {
  scope.done();
  });
 
+ it('should cache prior call to getEnv(), when GCE', async () => {
+ envDetect.clear();
+ const {auth, scopes} = mockGCE();
+ auth.getEnv();
+ const env = await auth.getEnv();
+ assert.strictEqual(env, envDetect.GCPEnv.COMPUTE_ENGINE);
+ });
+
+ it('should cache prior call to getEnv(), when GKE', async () => {
+ envDetect.clear();
+ const {auth, scopes} = mockGCE();
+ const scope = nock(host)
+ .get(`${instancePath}/attributes/cluster-name`)
+ .reply(200, {}, HEADERS);
+ auth.getEnv();
+ const env = await auth.getEnv();
+ assert.strictEqual(env, envDetect.GCPEnv.KUBERNETES_ENGINE);
+ scope.done();
+ });
+
  it('should get the current environment if GCF 8 and below', async () => {
  envDetect.clear();
  mockEnvVar('FUNCTION_NAME', 'DOGGY');