Added sampling function and blacklisted common urls and error messages

app/assets/javascripts/raven/raven_config.js

 import Raven from 'raven-js';
 
+const IGNORE_ERRORS = [
+  // Random plugins/extensions
+  'top.GLOBALS',
+  // See: http://blog.errorception.com/2012/03/tale-of-unfindable-js-error. html
+  'originalCreateNotification',
+  'canvas.contentDocument',
+  'MyApp_RemoveAllHighlights',
+  'http://tt.epicplay.com',
+  'Can\'t find variable: ZiteReader',
+  'jigsaw is not defined',
+  'ComboSearch is not defined',
+  'http://loading.retry.widdit.com/',
+  'atomicFindClose',
+  // Facebook borked
+  'fb_xd_fragment',
+  // ISP "optimizing" proxy - `Cache-Control: no-transform` seems to
+  // reduce this. (thanks @acdha)
+  // See http://stackoverflow.com/questions/4113268
+  'bmi_SafeAddOnload',
+  'EBCallBackMessageReceived',
+  // See http://toolbar.conduit.com/Developer/HtmlAndGadget/Methods/JSInjection.aspx
+  'conduitPage',
+];
+
+const IGNORE_URLS = [
+  // Facebook flakiness
+  /graph\.facebook\.com/i,
+  // Facebook blocked
+  /connect\.facebook\.net\/en_US\/all\.js/i,
+  // Woopra flakiness
+  /eatdifferent\.com\.woopra-ns\.com/i,
+  /static\.woopra\.com\/js\/woopra\.js/i,
+  // Chrome extensions
+  /extensions\//i,
+  /^chrome:\/\//i,
+  // Other plugins
+  /127\.0\.0\.1:4001\/isrunning/i,  // Cacaoweb
+  /webappstoolbarba\.texthelp\.com\//i,
+  /metrics\.itunes\.apple\.com\.edgesuite\.net\//i,
+];
+
+const SAMPLE_RATE = 95;
+
 const RavenConfig = {
+  IGNORE_ERRORS,
+  IGNORE_URLS,
+  SAMPLE_RATE,
   init(options = {}) {
     this.options = options;
 
@@ -13,6 +59,9 @@ const RavenConfig = {
     Raven.config(this.options.sentryDsn, {
       whitelistUrls: this.options.whitelistUrls,
       environment: this.options.isProduction ? 'production' : 'development',
+      ignoreErrors: this.IGNORE_ERRORS,
+      ignoreUrls: this.IGNORE_URLS,
+      shouldSendCallback: this.shouldSendSample,
     }).install();
   },
 
@@ -42,6 +91,10 @@ const RavenConfig = {
       },
     });
   },
+
+  shouldSendSample() {
+    return Math.random() * 100 <= this.SAMPLE_RATE;
+  },
 };
 
 export default RavenConfig;

spec/javascripts/raven/raven_config_spec.js

@@ -2,6 +2,28 @@ import Raven from 'raven-js';
 import RavenConfig from '~/raven/raven_config';
 
 describe('RavenConfig', () => {
+  describe('IGNORE_ERRORS', () => {
+    it('should be an array of strings', () => {
+      const areStrings = RavenConfig.IGNORE_ERRORS.every(error => typeof error === 'string');
+
+      expect(areStrings).toBe(true);
+    });
+  });
+
+  describe('IGNORE_URLS', () => {
+    it('should be an array of regexps', () => {
+      const areRegExps = RavenConfig.IGNORE_URLS.every(url => url instanceof RegExp);
+
+      expect(areRegExps).toBe(true);
+    });
+  });
+
+  describe('SAMPLE_RATE', () => {
+    it('should be a finite number', () => {
+      expect(typeof RavenConfig.SAMPLE_RATE).toEqual('number');
+    });
+  });
+
   describe('init', () => {
     let options;
 
@@ -76,6 +98,9 @@ describe('RavenConfig', () => {
       expect(Raven.config).toHaveBeenCalledWith(options.sentryDsn, {
         whitelistUrls: options.whitelistUrls,
         environment: 'production',
+        ignoreErrors: Raven.IGNORE_ERRORS,
+        ignoreUrls: Raven.IGNORE_URLS,
+        shouldSendCallback: Raven.shouldSendSample,
       });
     });
 
@@ -93,6 +118,9 @@ describe('RavenConfig', () => {
       expect(Raven.config).toHaveBeenCalledWith(options.sentryDsn, {
         whitelistUrls: options.whitelistUrls,
         environment: 'development',
+        ignoreErrors: Raven.IGNORE_ERRORS,
+        ignoreUrls: Raven.IGNORE_URLS,
+        shouldSendCallback: Raven.shouldSendSample,
       });
     });
   });
@@ -213,4 +241,38 @@ describe('RavenConfig', () => {
       });
     });
   });
+
+  describe('shouldSendSample', () => {
+    let randomNumber;
+
+    beforeEach(() => {
+      RavenConfig.SAMPLE_RATE = 50;
+
+      spyOn(Math, 'random').and.callFake(() => randomNumber);
+    });
+
+    it('should call Math.random', () => {
+      RavenConfig.shouldSendSample();
+
+      expect(Math.random).toHaveBeenCalled();
+    });
+
+    it('should return true if the sample rate is greater than the random number * 100', () => {
+      randomNumber = 0.1;
+
+      expect(RavenConfig.shouldSendSample()).toBe(true);
+    });
+
+    it('should return false if the sample rate is less than the random number * 100', () => {
+      randomNumber = 0.9;
+
+      expect(RavenConfig.shouldSendSample()).toBe(false);
+    });
+
+    it('should return true if the sample rate is equal to the random number * 100', () => {
+      randomNumber = 0.5;
+
+      expect(RavenConfig.shouldSendSample()).toBe(true);
+    });
+  });
 });