From 7eb07b1dfb29554af604b423cead45debd16e800 Mon Sep 17 00:00:00 2001
From: AshGDS <8880610+AshGDS@users.noreply.github.com>
Date: Wed, 11 Dec 2024 15:45:30 +0000
Subject: [PATCH] Limit GA4 search term tracking to 500 characters

---
 CHANGELOG.md                                  |  1 +
 .../analytics-ga4/ga4-core.js                 |  5 +++++
 .../analytics-ga4/ga4-core.spec.js            | 19 +++++++++++++++++++
 3 files changed, 25 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a4722d9064..4dde252ebb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@
 ## Unreleased
 
 * Add /media/ path to GA4 download link tracking ([PR #4491](https://github.com/alphagov/govuk_publishing_components/pull/4491/))
+* Limit GA4 search term tracking to 500 characters ([PR #4496](https://github.com/alphagov/govuk_publishing_components/pull/4496))
 
 ## 46.3.0
 
diff --git a/app/assets/javascripts/govuk_publishing_components/analytics-ga4/ga4-core.js b/app/assets/javascripts/govuk_publishing_components/analytics-ga4/ga4-core.js
index 6265794f9d..f4e1ccc162 100644
--- a/app/assets/javascripts/govuk_publishing_components/analytics-ga4/ga4-core.js
+++ b/app/assets/javascripts/govuk_publishing_components/analytics-ga4/ga4-core.js
@@ -340,6 +340,11 @@ window.GOVUK.analyticsGa4 = window.GOVUK.analyticsGa4 || {};
 
         if (isSearchResult) {
           var searchQuery = window.GOVUK.analyticsGa4.core.trackFunctions.standardiseSearchTerm(element.getAttribute('data-ga4-search-query'))
+
+          // Limit tracked search term to 500 characters
+          if (searchQuery) {
+            searchQuery = searchQuery.substring(0, 500)
+          }
           var variant = element.getAttribute('data-ga4-ecommerce-variant')
           DEFAULT_LIST_TITLE = 'Site search results'
         }
diff --git a/spec/javascripts/govuk_publishing_components/analytics-ga4/ga4-core.spec.js b/spec/javascripts/govuk_publishing_components/analytics-ga4/ga4-core.spec.js
index c89c40ec04..db31a98c5f 100644
--- a/spec/javascripts/govuk_publishing_components/analytics-ga4/ga4-core.spec.js
+++ b/spec/javascripts/govuk_publishing_components/analytics-ga4/ga4-core.spec.js
@@ -644,6 +644,25 @@ describe('GA4 core', function () {
         expect(builtEcommerceObject).toEqual(expectedEcommerceObject)
       })
 
+      it('limits ecommerce search term tracking to 500 characters', function () {
+        var veryLongString = ''
+
+        for (var i = 0; i < 600; i++) {
+          veryLongString = veryLongString + 'a'
+        }
+
+        resultsParentEl.setAttribute('data-ga4-search-query', veryLongString)
+
+        expectedEcommerceObject.search_results.term = veryLongString.substring(0, 500)
+
+        var builtEcommerceObject = GOVUK.analyticsGa4.core.ecommerceHelperFunctions.populateEcommerceSchema({
+          element: resultsParentEl,
+          resultsId: 'result-count'
+        })
+
+        expect(builtEcommerceObject).toEqual(expectedEcommerceObject)
+      })
+
       it('tracks variant and term for search results even when query is blank', function () {
         resultsParentEl.setAttribute('data-ga4-search-query', '')
         resultsParentEl.setAttribute('data-ga4-ecommerce-variant', 'upside-down')