feat: scan opengraph and twittercard style meta links (#217)

JustinBeckwith · web-flow · commit a8c0a431088b · 2020-12-24T14:55:24.000-08:00
diff --git a/src/links.ts b/src/links.ts
@@ -9,6 +9,7 @@ const linksAttr = {
   icon: ['command'],
   longdesc: ['frame', 'iframe'],
   manifest: ['html'],
+  content: ['meta'],
   poster: ['video'],
   pluginspage: ['embed'],
   pluginurl: ['embed'],
@@ -56,6 +57,17 @@ export function getLinks(source: string, baseUrl: string): ParsedUrl[] {
       ) {
         return;
       }
+
+      // Only for <meta content=""> tags, only validate the url if
+      // the content actually looks like a url
+      if (element.tagName === 'meta' && element.attribs['content']) {
+        try {
+          new URL(element.attribs['content']);
+        } catch (e) {
+          return;
+        }
+      }
+
       for (const v of values) {
         if (v) {
           const link = parseLink(v, realBaseUrl);
diff --git a/test/fixtures/twittercard/index.html b/test/fixtures/twittercard/index.html
@@ -0,0 +1,11 @@
+<html>
+<head>
+  <meta name="twitter:card" content="summary"></meta>
+  <meta name="twitter:creator" content="@justinbeckwith" />
+  <meta name="twitter:site" content="@justinbeckwith" />
+  <meta property="og:url" content="http://fake.local/" />
+  <meta property="og:title" content="A Twitter for My Sister" />
+  <meta property="og:description" content="In the early days, Twitter grew so quickly that it was almost impossible to add new features because engineers spent their time trying to keep the rocket ship from stalling." />
+  <meta property="og:image" content="http://fake.local" />
+</head>
+</html>
diff --git a/test/test.ts b/test/test.ts
@@ -445,4 +445,12 @@ describe('linkinator', () => {
     const err = results.links[0].failureDetails![0] as Error;
     assert.ok(/Nock: Disallowed net connect for/.test(err.message));
   });
+
+  it('should scan links in <meta content="URL"> tags', async () => {
+    const scope = nock('http://fake.local').head('/').reply(200);
+    const results = await check({path: 'test/fixtures/twittercard'});
+    assert.ok(results.passed);
+    scope.done();
+    assert.strictEqual(results.links.length, 2);
+  });
 });
