[8.11] Fixes rendering service config keys test (elastic#167937) (ela…

…stic#168143)

# Backport

This will backport the following commits from `main` to `8.11`:
- [Fixes rendering service config keys test
(elastic#167937)](elastic#167937)

<!--- Backport version: 8.9.7 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sqren/backport)

<!--BACKPORT [{"author":{"name":"Jeramy
Soucy","email":"[email protected]"},"sourceCommit":{"committedDate":"2023-10-05T17:59:19Z","message":"Fixes
rendering service config keys test (elastic#167937)\n\nCloses elastic#167142\r\nCloses
elastic#157126\r\n\r\n## Summary\r\n\r\nFortifies the rendering service tests
by introducing a retry loop to get\r\ninjected metadata after
navigation. The `kbn-injected-metadata` tag that\r\nwe're relying on in
this test gets removed some time after navigation\r\n(e.g. to
`.../render/core`). It appears that occasionally this test\r\nfails to
read the tag before it is removed.\r\n\r\nFlaky test
runner:\r\nhttps://buildkite.com/elastic/kibana-flaky-test-suite-runner/builds/3363\r\n\r\n---------\r\n\r\nCo-authored-by:
kibanamachine
<[email protected]>","sha":"335a751c00b2743d4e4adf53425f1fb45a54e883","branchLabelMapping":{"^v8.12.0$":"main","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["Team:Security","release_note:skip","backport:all-open","v8.11.0","v8.12.0"],"number":167937,"url":"https://github.com/elastic/kibana/pull/167937","mergeCommit":{"message":"Fixes
rendering service config keys test (elastic#167937)\n\nCloses elastic#167142\r\nCloses
elastic#157126\r\n\r\n## Summary\r\n\r\nFortifies the rendering service tests
by introducing a retry loop to get\r\ninjected metadata after
navigation. The `kbn-injected-metadata` tag that\r\nwe're relying on in
this test gets removed some time after navigation\r\n(e.g. to
`.../render/core`). It appears that occasionally this test\r\nfails to
read the tag before it is removed.\r\n\r\nFlaky test
runner:\r\nhttps://buildkite.com/elastic/kibana-flaky-test-suite-runner/builds/3363\r\n\r\n---------\r\n\r\nCo-authored-by:
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rendering service config keys test (elastic#167937)\n\nCloses elastic#167142\r\nCloses
elastic#157126\r\n\r\n## Summary\r\n\r\nFortifies the rendering service tests
by introducing a retry loop to get\r\ninjected metadata after
navigation. The `kbn-injected-metadata` tag that\r\nwe're relying on in
this test gets removed some time after navigation\r\n(e.g. to
`.../render/core`). It appears that occasionally this test\r\nfails to
read the tag before it is removed.\r\n\r\nFlaky test
runner:\r\nhttps://buildkite.com/elastic/kibana-flaky-test-suite-runner/builds/3363\r\n\r\n---------\r\n\r\nCo-authored-by:
kibanamachine
<[email protected]>","sha":"335a751c00b2743d4e4adf53425f1fb45a54e883"}}]}]
BACKPORT-->

Co-authored-by: Jeramy Soucy <[email protected]>

test/plugin_functional/test_suites/core_plugins/rendering.ts

@@ -31,6 +31,7 @@ export default function ({ getService }: PluginFunctionalProviderContext) {
   const deployment = getService('deployment');
   const find = getService('find');
   const testSubjects = getService('testSubjects');
+  const retry = getService('retry');
 
   const navigateTo = async (path: string) =>
     await browser.navigateTo(`${deployment.getHostPort()}${path}`);
@@ -47,7 +48,16 @@ export default function ({ getService }: PluginFunctionalProviderContext) {
 
   const getInjectedMetadata = () =>
     browser.execute(() => {
-      return JSON.parse(document.querySelector('kbn-injected-metadata')!.getAttribute('data')!);
+      const injectedMetadata = document.querySelector('kbn-injected-metadata');
+      // null/hasAttribute check and explicit error for better future troublehsooting
+      // (see https://github.com/elastic/kibana/issues/167142)
+      // The 'kbn-injected-metadata' tag that we're relying on here gets removed
+      // some time after navigation (e.g. to /render/core). It appears that
+      // occasionally this test fails to read the tag before it is removed.
+      if (!injectedMetadata?.hasAttribute('data')) {
+        throw new Error(`'kbn-injected-metadata.data' not found.`);
+      }
+      return JSON.parse(injectedMetadata.getAttribute('data')!);
     });
   const getUserSettings = () =>
     browser.execute(() => {
@@ -61,11 +71,17 @@ export default function ({ getService }: PluginFunctionalProviderContext) {
       return window.__RENDERING_SESSION__;
     });
 
-  // Failing: See https://github.com/elastic/kibana/issues/167142
-  describe.skip('rendering service', () => {
+  describe('rendering service', () => {
     it('exposes plugin config settings to authenticated users', async () => {
-      await navigateTo('/render/core');
-      const injectedMetadata = await getInjectedMetadata();
+      // This retry loop to get the injectedMetadata is to overcome flakiness
+      // (see comment in getInjectedMetadata)
+      let injectedMetadata: Partial<{ uiPlugins: any }> = { uiPlugins: undefined };
+      await retry.waitFor('injectedMetadata', async () => {
+        await navigateTo('/render/core');
+        injectedMetadata = await getInjectedMetadata();
+        return !!injectedMetadata;
+      });
+
       expect(injectedMetadata).to.not.be.empty();
       expect(injectedMetadata.uiPlugins).to.not.be.empty();
 
@@ -317,12 +333,19 @@ export default function ({ getService }: PluginFunctionalProviderContext) {
       // abundantly clear when the test fails that (A) Kibana is exposing a new key, or (B) Kibana is no longer exposing a key.
       const extra = _.difference(actualExposedConfigKeys, expectedExposedConfigKeys).sort();
       const missing = _.difference(expectedExposedConfigKeys, actualExposedConfigKeys).sort();
+
       expect({ extra, missing }).to.eql({ extra: [], missing: [] }, EXPOSED_CONFIG_SETTINGS_ERROR);
     });
 
     it('exposes plugin config settings to unauthenticated users', async () => {
-      await navigateTo('/render/core?isAnonymousPage=true');
-      const injectedMetadata = await getInjectedMetadata();
+      // This retry loop to get the injectedMetadata is to overcome flakiness
+      // (see comment in getInjectedMetadata)
+      let injectedMetadata: Partial<{ uiPlugins: any }> = { uiPlugins: undefined };
+      await retry.waitFor('injectedMetadata', async () => {
+        await navigateTo('/render/core?isAnonymousPage=true');
+        injectedMetadata = await getInjectedMetadata();
+        return !!injectedMetadata;
+      });
       expect(injectedMetadata).to.not.be.empty();
       expect(injectedMetadata.uiPlugins).to.not.be.empty();