Resolve share URLs from the instance host and ship 1200×630 Open Graph images.

Staging no longer advertises production canonicals, and Slack/social previews get a default hero card with template and article overrides.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/unit/siteMetadata.test.ts

@@ -1,13 +1,17 @@
 import { afterEach, describe, expect, it } from "vitest";
 import metadataMessages from "../../messages/en/metadata.json";
 import {
+  articleShareImages,
   buildRobots,
+  metadataBaseUrl,
   NO_INDEX_ROBOTS,
+  originFromHost,
   PRODUCTION_SITE_ORIGIN,
   resolveRequestHost,
   robotsForPublishedRule,
   routeMetadata,
   sitemapUrl,
+  templatesShareImages,
 } from "../../lib/siteMetadata";
 
 const ORIGINAL_SITE_INDEXING = process.env.SITE_INDEXING;
@@ -27,6 +31,13 @@ afterEach(() => {
 });
 
 describe("routeMetadata", () => {
+  const defaultImage = {
+    url: "/assets/marketing/og-image.png",
+    width: 1200,
+    height: 630,
+    alt: metadataMessages.shareImage.defaultAlt,
+  };
+
   it("sets a path canonical, stripping trailing slashes and query strings", () => {
     expect(routeMetadata("/about").alternates?.canonical).toBe("/about");
     expect(routeMetadata("/about/").alternates?.canonical).toBe("/about");
@@ -37,14 +48,54 @@ describe("routeMetadata", () => {
     );
   });
 
+  it("sets og:url from the same path so metadataBase can add the host", () => {
+    expect(routeMetadata("/about").openGraph?.url).toBe("/about");
+    expect(routeMetadata("/").openGraph?.url).toBe("/");
+  });
+
+  it("ships a 1200×630 default share image on og and twitter", () => {
+    const meta = routeMetadata("/learn");
+    expect(meta.openGraph?.images).toEqual([defaultImage]);
+    expect(meta.twitter?.images).toEqual([defaultImage.url]);
+  });
+
   it("keeps caller metadata while overriding a parent canonical", () => {
-    expect(
-      routeMetadata("/learn", { title: "Learn", description: "Copy" }),
-    ).toEqual({
+    const meta = routeMetadata("/learn", {
       title: "Learn",
       description: "Copy",
-      alternates: { canonical: "/learn" },
     });
+    expect(meta.title).toBe("Learn");
+    expect(meta.description).toBe("Copy");
+    expect(meta.alternates?.canonical).toBe("/learn");
+    expect(meta.openGraph?.url).toBe("/learn");
+  });
+
+  it("lets templates and articles replace the default share image", () => {
+    const templates = templatesShareImages();
+    const templateMeta = routeMetadata("/templates", {
+      openGraph: { images: templates },
+    });
+    expect(templateMeta.openGraph?.images).toEqual(templates);
+    expect(templateMeta.twitter?.images).toEqual([templates[0]?.url]);
+
+    const article = articleShareImages(
+      "how-chaos-concentrates-control",
+      "How Chaos Concentrates Control",
+    );
+    const articleMeta = routeMetadata("/blog/how-chaos-concentrates-control", {
+      openGraph: { images: article },
+    });
+    expect(articleMeta.openGraph?.images).toEqual([
+      {
+        url: "/content/blog/how-chaos-concentrates-control-og.png",
+        width: 1200,
+        height: 630,
+        alt: "How Chaos Concentrates Control",
+      },
+    ]);
+    expect(articleMeta.twitter?.images).toEqual([
+      "/content/blog/how-chaos-concentrates-control-og.png",
+    ]);
   });
 });
 
@@ -70,6 +121,30 @@ describe("resolveRequestHost", () => {
   });
 });
 
+describe("originFromHost", () => {
+  it("uses CLOUDRON_APP_ORIGIN when no host is given", () => {
+    process.env.CLOUDRON_APP_ORIGIN = "https://staging.communityrule.info";
+    expect(originFromHost(null)).toBe("https://staging.communityrule.info");
+    expect(metadataBaseUrl().origin).toBe("https://staging.communityrule.info");
+  });
+
+  it("falls back to production when neither host nor app origin is set", () => {
+    delete process.env.CLOUDRON_APP_ORIGIN;
+    expect(originFromHost(null)).toBe(PRODUCTION_SITE_ORIGIN);
+  });
+
+  it("builds https origins from public hostnames", () => {
+    expect(originFromHost("staging.communityrule.info")).toBe(
+      "https://staging.communityrule.info",
+    );
+    expect(originFromHost("communityrule.com")).toBe(PRODUCTION_SITE_ORIGIN);
+  });
+
+  it("keeps http for localhost so local previews resolve", () => {
+    expect(originFromHost("localhost:3000")).toBe("http://localhost:3000");
+  });
+});
+
 describe("buildRobots", () => {
   it("disallows crawlers on staging and unknown hosts", () => {
     expect(buildRobots("staging.communityrule.info")).toEqual({