changing default currency file (#3414)

* changing default currency file * using defaultRate in the case of rate file not returning * Adding date macro * added unit tests for date macro support in currency file url, and small fix to date macro in currency.js * replaced string concatenations with string literals * removed unnecessary parens
prebid · Jan 9, 2019 · 4b53954 · 4b53954
1 parent 90656ee
commit 4b53954
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Showing 2 changed files with 71 additions and 4 deletions.
diff --git a/modules/currency.js b/modules/currency.js
@@ -5,7 +5,7 @@ import * as utils from 'src/utils';
 import { config } from 'src/config';
 import { hooks } from 'src/hook.js';
 
-const DEFAULT_CURRENCY_RATE_URL = 'https://currency.prebid.org/latest.json';
+const DEFAULT_CURRENCY_RATE_URL = 'https://cdn.jsdelivr.net/gh/prebid/currency-file@1/latest.json?date=$$TODAY$$';
 const CURRENCY_RATE_PRECISION = 4;
 
 var bidResponseQueue = [];
@@ -34,7 +34,7 @@ var defaultRates;
  *  {
  *    rubicon: 'USD'
  *  }
- * @param  {string} [config.conversionRateFile = 'http://currency.prebid.org/latest.json']
+ * @param  {string} [config.conversionRateFile = 'URL pointing to conversion file']
  *  Optional path to a file containing currency conversion data.  Prebid.org hosts a file that is used as the default,
  *  if not specified.
  * @param  {object} [config.rates]
@@ -60,6 +60,10 @@ export function setConfig(config) {
 
   if (typeof config.defaultRates === 'object') {
     defaultRates = config.defaultRates;
+
+    // set up the default rates to be used if the rate file doesn't get loaded in time
+    currencyRates.conversions = defaultRates;
+    currencyRatesLoaded = true;
   }
 
   if (typeof config.adServerCurrency === 'string') {
@@ -70,6 +74,25 @@ export function setConfig(config) {
       utils.logInfo('currency using override conversionRateFile:', config.conversionRateFile);
       url = config.conversionRateFile;
     }
+
+    // see if the url contains a date macro
+    // this is a workaround to the fact that jsdelivr doesn't currently support setting a 24-hour HTTP cache header
+    // So this is an approach to let the browser cache a copy of the file each day
+    // We should remove the macro once the CDN support a day-level HTTP cache setting
+    const macroLocation = url.indexOf('$$TODAY$$');
+    if (macroLocation !== -1) {
+      // get the date to resolve the macro
+      const d = new Date();
+      let month = `${d.getMonth() + 1}`;
+      let day = `${d.getDate()}`;
+      if (month.length < 2) month = `0${month}`;
+      if (day.length < 2) day = `0${day}`;
+      const todaysDate = `${d.getFullYear()}${month}${day}`;
+
+      // replace $$TODAY$$ with todaysDate
+      url = `${url.substring(0, macroLocation)}${todaysDate}${url.substring(macroLocation + 9, url.length)}`;
+    }
+
     initCurrency(url);
   } else {
     // currency support is disabled, setting defaults
@@ -84,8 +107,6 @@ config.getConfig('currency', config => setConfig(config.currency));
 
 function errorSettingsRates(msg) {
   if (defaultRates) {
-    currencyRates.conversions = defaultRates;
-    currencyRatesLoaded = true;
     utils.logWarn(msg);
     utils.logWarn('Currency failed loading rates, falling back to currency.defaultRates');
   } else {

diff --git a/test/spec/modules/currency_spec.js b/test/spec/modules/currency_spec.js
@@ -17,6 +17,8 @@ var expect = require('chai').expect;
 
 describe('currency', function () {
   let fakeCurrencyFileServer;
+  let sandbox;
+  let clock;
 
   let fn = sinon.spy();
   let hookFn = createHook('asyncSeries', fn, 'addBidResponse');
@@ -30,6 +32,16 @@ describe('currency', function () {
   });
 
   describe('setConfig', function () {
+    beforeEach(function() {
+      sandbox = sinon.sandbox.create();
+      clock = sinon.useFakeTimers(1047010195974);
+    });
+
+    afterEach(function () {
+      sandbox.restore();
+      clock.restore();
+    });
+
     it('results in currencySupportEnabled = false when currency not configured', function () {
       setConfig({});
       expect(currencySupportEnabled).to.equal(false);
@@ -42,6 +54,40 @@ describe('currency', function () {
       expect(currencyRates.dataAsOf).to.equal('2017-04-25');
       expect(currencySupportEnabled).to.equal(true);
     });
+
+    it('date macro token $$TODAY$$ is replaced by current date (formatted as yyyymmdd)', function () {
+      // RESET to request currency file (specifically url value for this test)
+      setConfig({ 'adServerCurrency': undefined });
+
+      // date macro should replace $$TODAY$$ with date when DEFAULT_CURRENCY_RATE_URL is used
+      setConfig({ 'adServerCurrency': 'JPY' });
+      fakeCurrencyFileServer.respond();
+      expect(fakeCurrencyFileServer.requests[0].url).to.equal('https://cdn.jsdelivr.net/gh/prebid/currency-file@1/latest.json?date=20030306');
+
+      // date macro should not modify 'conversionRateFile' if TOKEN is not found
+      setConfig({
+        'adServerCurrency': 'JPY',
+        'conversionRateFile': 'http://test.net/currency.json?date=foobar'
+      });
+      fakeCurrencyFileServer.respond();
+      expect(fakeCurrencyFileServer.requests[1].url).to.equal('http://test.net/currency.json?date=foobar');
+
+      // date macro should replace $$TODAY$$ with date for 'conversionRateFile' is configured
+      setConfig({
+        'adServerCurrency': 'JPY',
+        'conversionRateFile': 'http://test.net/currency.json?date=$$TODAY$$'
+      });
+      fakeCurrencyFileServer.respond();
+      expect(fakeCurrencyFileServer.requests[2].url).to.equal('http://test.net/currency.json?date=20030306');
+
+      // MULTIPLE TOKENS used in a url is not supported. Only the TOKEN at left-most position is REPLACED
+      setConfig({
+        'adServerCurrency': 'JPY',
+        'conversionRateFile': 'http://test.net/$$TODAY$$/currency.json?date=$$TODAY$$'
+      });
+      fakeCurrencyFileServer.respond();
+      expect(fakeCurrencyFileServer.requests[3].url).to.equal('http://test.net/20030306/currency.json?date=$$TODAY$$');
+    });
   });
 
   describe('bidder override', function () {