Merge pull request #3228 from alphagov/add-analytics-modules-error-check

Add GA4 modules error checking

CHANGELOG.md

@@ -9,6 +9,7 @@
 
 ## Unreleased
 
+* Add GA4 modules error checking ([PR #3228](https://github.com/alphagov/govuk_publishing_components/pull/3228))
 * Add classes to align text in Govspeak tables ([PR #3217](https://github.com/alphagov/govuk_publishing_components/pull/3217))
 * Make links bold at all viewports on navbar menu ([PR #3219](https://github.com/alphagov/govuk_publishing_components/pull/3219))
 * Add our 'assets' domain as a domain that should run our analytics ([PR #3224](https://github.com/alphagov/govuk_publishing_components/pull/3224))

app/assets/javascripts/govuk_publishing_components/analytics-ga4/init-ga4.js

@@ -2,8 +2,6 @@ window.GOVUK = window.GOVUK || {}
 window.GOVUK.analyticsGa4 = window.GOVUK.analyticsGa4 || {}
 
 var initFunction = function () {
-  // to be added: digital identity consent mechanism
-
   var consentCookie = window.GOVUK.getConsentCookie()
 
   if (consentCookie && consentCookie.usage) {
@@ -16,10 +14,14 @@ var initFunction = function () {
     for (var property in analyticsModules) {
       var module = analyticsModules[property]
       if (typeof module.init === 'function') {
-        module.init()
+        try {
+          module.init()
+        } catch (e) {
+          // if there's a problem with the module, catch the error to allow other modules to start
+          console.warn('Error starting analytics module ' + property + ': ' + e.message, window.location)
+        }
       }
     }
-    // to be added: cross domain tracking code
   } else {
     window.addEventListener('cookie-consent', window.GOVUK.analyticsGa4.init)
   }

spec/javascripts/govuk_publishing_components/analytics-ga4/init-ga4.spec.js

@@ -11,11 +11,13 @@ describe('Initialising GA4', function () {
 
   describe('when consent is given', function () {
     var test = {
-      functionThatMightBeCalled: function () {}
+      functionThatMightBeCalled: function () {},
+      functionThatShouldNotBeCalled: function () {}
     }
 
     beforeEach(function () {
       spyOn(test, 'functionThatMightBeCalled')
+      spyOn(test, 'functionThatShouldNotBeCalled')
       GOVUK.analyticsGa4.analyticsModules.Test = function () {}
       GOVUK.analyticsGa4.analyticsModules.Test.init = function () { test.functionThatMightBeCalled() }
     })
@@ -46,6 +48,27 @@ describe('Initialising GA4', function () {
 
       expect(GOVUK.analyticsGa4).not.toEqual({})
     })
+
+    it('initialises following modules even if this one errors', function () {
+      // module with a deliberate error in it
+      GOVUK.analyticsGa4.analyticsModules.TestError = function () {}
+      GOVUK.analyticsGa4.analyticsModules.TestError.init = function () {
+        throw new Error('This is a deliberate error')
+        test.functionThatShouldNotBeCalled() // eslint-disable-line no-unreachable
+      }
+
+      GOVUK.analyticsGa4.analyticsModules.TestNotError = function () {}
+      GOVUK.analyticsGa4.analyticsModules.TestNotError.init = function () { test.functionThatMightBeCalled() }
+
+      GOVUK.setCookie('cookies_policy', '{"essential":true,"settings":true,"usage":true,"campaigns":true}')
+      GOVUK.analyticsGa4.init()
+
+      expect(test.functionThatShouldNotBeCalled.calls.count()).toEqual(0)
+      expect(test.functionThatMightBeCalled.calls.count()).toEqual(2)
+
+      delete GOVUK.analyticsGa4.analyticsModules.TestError
+      delete GOVUK.analyticsGa4.analyticsModules.TestNotError
+    })
   })
 
   describe('Modules depending on cookie consent to run', function () {