Routing: Fix links to different port from being treated as internal links (#45192)

* Add some failing tests that trigger the bug

* start at refactor of stripBaseFromUrl

packages/grafana-data/src/utils/location.test.ts

@@ -3,7 +3,7 @@ import { locationUtil } from './location';
 describe('locationUtil', () => {
   const { location } = window;
 
-  beforeAll(() => {
+  beforeEach(() => {
     // @ts-ignore
     delete window.location;
 
@@ -21,11 +21,12 @@ describe('locationUtil', () => {
     };
   });
 
-  afterAll(() => {
+  afterEach(() => {
     window.location = location;
   });
 
-  describe('strip base when appSubUrl configured', () => {
+  describe('stripBaseFromUrl', () => {
+    describe('when appSubUrl configured', () => {
       beforeEach(() => {
         locationUtil.initialize({
           config: { appSubUrl: '/subUrl' } as any,
@@ -61,7 +62,7 @@ describe('locationUtil', () => {
       });
     });
 
-  describe('strip base when appSubUrl not configured', () => {
+    describe('when appSubUrl not configured', () => {
       beforeEach(() => {
         locationUtil.initialize({
           config: {} as any,
@@ -81,6 +82,39 @@ describe('locationUtil', () => {
       });
     });
 
+    describe('when origin does not have a port in it', () => {
+      beforeEach(() => {
+        window.location = {
+          ...location,
+          hash: '#hash',
+          host: 'www.domain.com',
+          hostname: 'www.domain.com',
+          href: 'http://www.domain.com/path/b?search=a&b=c&d#hash',
+          origin: 'http://www.domain.com',
+          pathname: '/path/b',
+          port: '',
+          protocol: 'http:',
+          search: '?search=a&b=c&d',
+        };
+      });
+
+      test('relative url', () => {
+        const urlWithoutMaster = locationUtil.stripBaseFromUrl('/subUrl/grafana/');
+        expect(urlWithoutMaster).toBe('/subUrl/grafana/');
+      });
+
+      test('URL with same host, different port', () => {
+        const urlWithoutMaster = locationUtil.stripBaseFromUrl('http://www.domain.com:9877/subUrl/grafana/');
+        expect(urlWithoutMaster).toBe('http://www.domain.com:9877/subUrl/grafana/');
+      });
+
+      test('URL of a completely different origin', () => {
+        const urlWithoutMaster = locationUtil.stripBaseFromUrl('http://www.another-domain.com/subUrl/grafana/');
+        expect(urlWithoutMaster).toBe('http://www.another-domain.com/subUrl/grafana/');
+      });
+    });
+  });
+
   describe('updateSearchParams', () => {
     beforeEach(() => {
       locationUtil.initialize({

packages/grafana-data/src/utils/location.ts

@@ -7,22 +7,43 @@ let grafanaConfig: GrafanaConfig = { appSubUrl: '' } as any;
 let getTimeRangeUrlParams: () => RawTimeRange;
 let getVariablesUrlParams: (scopedVars?: ScopedVars) => UrlQueryMap;
 
+const maybeParseUrl = (input: string): URL | undefined => {
+  try {
+    return new URL(input);
+  } catch {
+    return undefined;
+  }
+};
+
 /**
  *
  * @param url
  * @internal
  */
-const stripBaseFromUrl = (url: string): string => {
+const stripBaseFromUrl = (urlOrPath: string): string => {
+  // Will only return a URL object if the input is actually a valid URL
+  const parsedUrl = maybeParseUrl(urlOrPath);
+  if (parsedUrl) {
+    // If the input is a URL, and for a different origin that we're on, just bail
+    // and return it. There's no need to strip anything from it
+    if (parsedUrl.origin !== window.location.origin) {
+      return urlOrPath;
+    }
+  }
+
   const appSubUrl = grafanaConfig.appSubUrl ?? '';
   const stripExtraChars = appSubUrl.endsWith('/') ? 1 : 0;
-  const isAbsoluteUrl = url.startsWith('http');
+  const isAbsoluteUrl = urlOrPath.startsWith('http');
+
   let segmentToStrip = appSubUrl;
 
-  if (!url.startsWith('/') || isAbsoluteUrl) {
+  if (!urlOrPath.startsWith('/') || isAbsoluteUrl) {
     segmentToStrip = `${window.location.origin}${appSubUrl}`;
   }
 
-  return url.length > 0 && url.indexOf(segmentToStrip) === 0 ? url.slice(segmentToStrip.length - stripExtraChars) : url;
+  return urlOrPath.length > 0 && urlOrPath.indexOf(segmentToStrip) === 0
+    ? urlOrPath.slice(segmentToStrip.length - stripExtraChars)
+    : urlOrPath;
 };
 
 /**