Extend expiry of user benefits cookies to 30 days

Previouly they were short lived (1-2 days) but this resulted in edge
cases where if a signed in user didn't visit the site for more than a
couple of days, when they returned their first page view wouldn't reflect
their benefits (i.e. they would see ads). This is due to a race
condition between the user benefits refresh and the ads code. However,
we don't want to delay ads until after the user benefits have been
refreshed as that would impact performance. So instead, extend the
expiry of the cookie.

Note: this may result in a user getting benefits they no longer have on
the first returning pageview, but this will be correct from the second
page view onwards. We think this is OK.

Author: tjmw

src/server/lib/user-features.ts

@@ -31,7 +31,7 @@ export const setUserFeatureCookies = async ({
 	accessToken: string;
 	res: Response;
 }): Promise<void> => {
-	// call the members-data-api to get the user's attributes/products if any
+	// call the user-benefits-api to get the user's attributes/products if any
 
 	const userBenefits = await getUserBenefits({
 		accessToken,
@@ -74,6 +74,8 @@ const createCookie = ({
 	});
 };
 
+const USER_BENEFITS_COOKIE_EXPIRATION_IN_DAYS = 30;
+
 /**
  * https://github.com/guardian/dotcom-rendering/blob/a0eff55ee7fedf08b785557fceaa0f4f7265e0df/dotcom-rendering/src/client/userFeatures/user-features.ts
  *
@@ -95,7 +97,7 @@ const persistUserBenefitsCookies = ({
 	createCookie({
 		name: USER_BENEFITS_EXPIRY_COOKIE,
 		res,
-		daysTillExpiry: 1,
+		daysTillExpiry: USER_BENEFITS_COOKIE_EXPIRATION_IN_DAYS,
 	});
 	if (userBenefits?.benefits?.includes('hideSupportMessaging')) {
 		createCookie({
@@ -106,11 +108,18 @@ const persistUserBenefitsCookies = ({
 	}
 	// Allow reject all cookie
 	if (userBenefits?.benefits?.includes('allowRejectAll')) {
-		createCookie({ name: ALLOW_REJECT_ALL_COOKIE, res, daysTillExpiry: 1 });
+		createCookie({
+			name: ALLOW_REJECT_ALL_COOKIE,
+			res,
+			daysTillExpiry: USER_BENEFITS_COOKIE_EXPIRATION_IN_DAYS,
+		});
 	}
-	// Ad free user cookie is set for 2 days
-	// https://github.com/guardian/frontend/blob/f17fe93c542fbd448392a0687d0b92f35796097a/static/src/javascripts/projects/common/modules/commercial/user-features.ts#L128
+	// Ad free user cookie
 	if (userBenefits?.benefits?.includes('adFree')) {
-		createCookie({ name: AD_FREE_USER_COOKIE, res, daysTillExpiry: 2 });
+		createCookie({
+			name: AD_FREE_USER_COOKIE,
+			res,
+			daysTillExpiry: USER_BENEFITS_COOKIE_EXPIRATION_IN_DAYS,
+		});
 	}
 };