fix #415: move throttle to env vars and test

.env-dist

@@ -44,3 +44,7 @@ HIBP_RELOAD_BREACHES_TIMER=600
 # HIBP API for range search and subscription
 HIBP_KANON_API_ROOT="https://api.haveibeenpwned.com"
 HIBP_KANON_API_TOKEN=""
+# How many seconds to wait before retrying an HIBP request
+HIBP_THROTTLE_DELAY=2000
+# Max number of times to try an HIBP request before throwing error
+HIBP_THROTTLE_MAX_TRIES=5

app-constants.js

@@ -29,6 +29,8 @@ const kEnvironmentVariables = [
   "HIBP_API_ROOT",
   "HIBP_API_TOKEN",
   "HIBP_RELOAD_BREACHES_TIMER",
+  "HIBP_THROTTLE_DELAY",
+  "HIBP_THROTTLE_MAX_TRIES",
   "DATABASE_URL",
   "SERVER_URL",
   "DELETE_UNVERIFIED_SUBSCRIBERS_TIMER",

hibp.js

@@ -10,8 +10,6 @@ const pkg = require("./package.json");
 
 const DOMPurify = createDOMPurify((new JSDOM("")).window);
 const HIBP_USER_AGENT = `${pkg.name}/${pkg.version}`;
-const HIBP_THROTTLE_DELAY = 2000;
-const HIBP_THROTTLE_MAX_RETRIES = 5;
 
 
 const HIBP = {
@@ -25,18 +23,19 @@ const HIBP = {
     return Object.assign(options, hibpOptions);
   },
 
-  async _throttledGot (url, reqOptions, retryCount = 0) {
+  async _throttledGot (url, reqOptions, tryCount = 1) {
     try {
       return await got(url, reqOptions);
     } catch (err) {
       console.error("got an error: " + err);
       if (err.statusCode === 429) {
-        console.log("got a 429, retryCount: ", retryCount);
-        if (retryCount >= HIBP_THROTTLE_MAX_RETRIES) {
+        console.log("got a 429, tryCount: ", tryCount);
+        if (tryCount >= AppConstants.HIBP_THROTTLE_MAX_TRIES) {
           throw new Error(err.message);
         } else {
-          await new Promise(resolve => setTimeout(resolve, HIBP_THROTTLE_DELAY * retryCount));
-          return await this._throttledGot(url, reqOptions, retryCount)
+          tryCount++;
+          await new Promise(resolve => setTimeout(resolve, AppConstants.HIBP_THROTTLE_DELAY * tryCount));
+          return await this._throttledGot(url, reqOptions, tryCount);
         }
       } else {
         throw new Error("Error connecting to HIBP.");

tests/hibp.test.js

@@ -3,6 +3,7 @@
 const got = require("got");
 
 const AppConstants = require("../app-constants");
+const getSha1 = require("../sha1-utils");
 const hibp = require("../hibp");
 
 const { testBreaches } = require("./test-breaches");
@@ -59,3 +60,18 @@ test("filterOutUnsafeBreaches removes sensitive breaches", async() => {
     expect(breach.IsVerified).toBe(true);
   }
 });
+
+
+test("getBreachesForEmail HIBP responses with status of 429 cause throttled retries up to HIBP_THROTTLE_MAX_TRIES", async() => {
+  // Assumes running with max tries of 3 and delay of 1000
+  jest.setTimeout(20000);
+  got.mockClear();
+  got.mockRejectedValue( { statusCode: 429 });
+
+  await expect(hibp.getBreachesForEmail(getSha1("unverifiedemail@test.com"), testBreaches)).rejects.toThrow();
+
+  const gotCalls = got.mock.calls;
+  expect(gotCalls.length).toEqual(Number(AppConstants.HIBP_THROTTLE_MAX_TRIES));
+
+  jest.setTimeout(5000);
+});