Added full flow test for click tracking (#15546)

refs TryGhost/Product#1967

This tests the full flow of publishing a newsletter, and then checking
that clicked links will increase the click count, generate events for
the member which clicked the link as well as the redirects contain the
correct query params.

ghost/core/test/e2e-server/click-tracking.test.js

@@ -0,0 +1,114 @@
+const assert = require('assert');
+const fetch = require('node-fetch').default;
+const {agentProvider, mockManager, fixtureManager} = require('../utils/e2e-framework');
+const urlUtils = require('../../core/shared/url-utils');
+
+describe('Click Tracking', function () {
+    let agent;
+
+    before(async function () {
+        agent = await agentProvider.getAdminAPIAgent();
+        await fixtureManager.init('newsletters', 'members:newsletters');
+        await agent.loginAsOwner();
+    });
+
+    beforeEach(function () {
+        mockManager.mockMail();
+    });
+
+    afterEach(function () {
+        mockManager.restore();
+    });
+
+    it('Full test', async function () {
+        const {body: {posts: [draft]}} = await agent.post('/posts/', {
+            body: {
+                posts: [{
+                    title: 'My Newsletter'
+                }]
+            }
+        });
+
+        const newsletterSlug = fixtureManager.get('newsletters', 0).slug;
+        const {body: {posts: [post]}} = await agent.put(
+            `/posts/${draft.id}/?newsletter=${newsletterSlug}`,
+            {
+                body: {
+                    posts: [{
+                        updated_at: draft.updated_at,
+                        status: 'published'
+                    }]
+                }
+            }
+        );
+
+        const {body: {links}} = await agent.get(
+            `/links/?filter=post_id:${post.id}`
+        );
+
+        /** @type {(url: string) => Promise<import('node-fetch').Response>} */
+        const fetchWithoutFollowingRedirect = url => fetch(url, {redirect: 'manual'});
+
+        const siteUrl = new URL(urlUtils.urlFor('home', true));
+
+        let internalRedirectHappened = false;
+        let externalRedirectHappened = false;
+        for (const link of links) {
+            const res = await fetchWithoutFollowingRedirect(link.link.from);
+            const redirectedToUrl = new URL(res.headers.get('location'));
+
+            // startsWith is a little dirty, but we need this because siteUrl
+            // can have a path when Ghost is hosted on a subdomain.
+            const isInternal = redirectedToUrl.href.startsWith(siteUrl.href);
+
+            if (isInternal) {
+                internalRedirectHappened = true;
+
+                assert(redirectedToUrl.searchParams.get('attribution_id'), 'attribution_id should be present on internal redirects');
+                assert(redirectedToUrl.searchParams.get('attribution_type'), 'attribution_type should be present on internal redirects');
+            } else {
+                externalRedirectHappened = true;
+
+                assert(!redirectedToUrl.searchParams.get('attribution_id'), 'attribution_id should not be present on internal redirects');
+                assert(!redirectedToUrl.searchParams.get('attribution_type'), 'attribution_type should not be present on internal redirects');
+            }
+
+            assert(redirectedToUrl.searchParams.get('ref'), 'ref should be present on all redirects');
+        }
+
+        assert(internalRedirectHappened);
+        assert(externalRedirectHappened);
+
+        const {body: {members}} = await agent.get(
+            `/members/`
+        );
+
+        const linkToClick = links[0];
+        const memberToClickLink = members[0];
+
+        const urlOfLinkToClick = new URL(linkToClick.link.from);
+
+        urlOfLinkToClick.searchParams.set('m', memberToClickLink.uuid);
+
+        const previousClickCount = linkToClick.count.clicks;
+
+        await fetchWithoutFollowingRedirect(urlOfLinkToClick.href);
+
+        const {body: {links: [clickedLink]}} = await agent.get(
+            `/links/?filter=post_id:${post.id}`
+        );
+
+        const clickCount = clickedLink.count.clicks;
+
+        const {body: {events: clickEvents}} = await agent.get(
+            `/members/events/?filter=data.member_id:${memberToClickLink.id}${encodeURIComponent('+')}type:click_event`
+        );
+
+        const clickEvent = clickEvents.find((/** @type any */ event) => {
+            return event.data.post.id === post.id && event.data.link.from === urlOfLinkToClick.pathname;
+        });
+
+        assert(clickEvent);
+        assert(previousClickCount + 1 === clickCount);
+    });
+});