Merge pull request guardian#24077 from guardian/toggle-force-send-metrics

Force send core web vital data for Improve/Collective skin

Author: mxdvl

static/src/javascripts/projects/commercial/modules/header-bidding/prebid/prebid.ts

@@ -3,6 +3,7 @@ import { isString, log } from '@guardian/libs';
 import { captureCommercialMetrics } from 'commercial/commercial-metrics';
 import type { Advert } from 'commercial/modules/dfp/Advert';
 import config from '../../../../../lib/config';
+import { setForceSendMetrics } from '../../../../common/modules/analytics/forceSendMetrics';
 import { dfpEnv } from '../../dfp/dfp-env';
 import { getAdvertById } from '../../dfp/get-advert-by-id';
 import { getHeaderBiddingAdSlots } from '../slot-config';
@@ -330,7 +331,14 @@ const initialise = (window: Window, framework = 'tcfv2'): void => {
 		 * */
 		advert.hasPrebidSize = true;
 
-		if (data.bidderCode === 'improvedigital') captureCommercialMetrics();
+		/**
+		 * If improve skin has won auction, toggle force send metrics on.
+		 * TODO remove after improve skin release.
+		 * */
+		if (data.bidderCode === 'improvedigital') {
+			setForceSendMetrics(true);
+			captureCommercialMetrics();
+		}
 	});
 };
 

static/src/javascripts/projects/common/modules/analytics/coreVitals.ts

@@ -1,6 +1,7 @@
 import { getCookie } from '@guardian/libs';
 import { getCLS, getFCP, getFID, getLCP, getTTFB } from 'web-vitals';
 import reportError from 'lib/report-error';
+import { forceSendMetrics } from './forceSendMetrics';
 import { shouldCaptureMetrics } from './shouldCaptureMetrics';
 
 type CoreWebVitalsPayload = {
@@ -30,21 +31,19 @@ const jsonData: CoreWebVitalsPayload = {
 	ttfb: null,
 };
 
+// By default, sample 1% of users
+const userInSample = Math.random() < 1 / 100;
+// unless we are forcing metrics for this user because they are participating in an AB test
+// for which we need to capture all metrics
+const captureMetrics = shouldCaptureMetrics();
+// or we are force sending for this page view for some other reason with forceSendMetrics.
+
 /**
- * Sends core web vitals data for a sample of page views to the data lake.
+ * Calls functions of web-vitals library to collect core web vitals data, registering callbacks which
+ * send it to the data lake for a sample of page views.
  * Equivalent dotcom-rendering functionality is here: https://git.io/JBRIt
  */
 export const coreVitals = (): void => {
-	// By default, sample 1% of users
-	const inSample = Math.random() < 1 / 100;
-
-	// Unless we are forcing metrics for this user
-	const captureMetrics = shouldCaptureMetrics();
-
-	if (!captureMetrics && !inSample) {
-		return;
-	}
-
 	type CoreVitalsArgs = {
 		name: string;
 		value: number;
@@ -59,6 +58,10 @@ export const coreVitals = (): void => {
 	};
 
 	const jsonToSend = ({ name, value }: CoreVitalsArgs): void => {
+		if (!captureMetrics && !userInSample && !forceSendMetrics) {
+			return;
+		}
+
 		switch (name) {
 			case 'FCP':
 				jsonData.fcp = nineDigitPrecision(value);

static/src/javascripts/projects/common/modules/analytics/forceSendMetrics.ts

@@ -0,0 +1,5 @@
+export let forceSendMetrics = false;
+
+export const setForceSendMetrics = (val: boolean): void => {
+	forceSendMetrics = val;
+};