Updated CatalogKindHeader to respect query param changes

Signed-off-by: Andre Wanlin <awanlin@rapidrtc.com>

.changeset/great-hounds-allow.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-catalog': patch
+---
+
+Updated `CatalogKindHeader` to respond to external changes to query parameters in the URL, such as two sidebar links that apply different catalog filters.

plugins/catalog/src/components/CatalogKindHeader/CatalogKindHeader.test.tsx

@@ -135,4 +135,34 @@ describe('<CatalogKindHeader />', () => {
       kind: new EntityKindFilter('template'),
     });
   });
+
+  it('responds to external queryParameters changes', async () => {
+    const updateFilters = jest.fn();
+    const rendered = await renderWithEffects(
+      <MockEntityListContextProvider
+        value={{
+          updateFilters,
+          queryParameters: { kind: ['Component'] },
+        }}
+      >
+        <CatalogKindHeader />
+      </MockEntityListContextProvider>,
+    );
+    expect(updateFilters).toHaveBeenLastCalledWith({
+      kind: new EntityKindFilter('Components'),
+    });
+    rendered.rerender(
+      <MockEntityListContextProvider
+        value={{
+          updateFilters,
+          queryParameters: { kind: ['Template'] },
+        }}
+      >
+        <CatalogKindHeader />
+      </MockEntityListContextProvider>,
+    );
+    expect(updateFilters).toHaveBeenLastCalledWith({
+      kind: new EntityKindFilter('Template'),
+    });
+  });
 });

plugins/catalog/src/components/CatalogKindHeader/CatalogKindHeader.tsx

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import React, { useEffect, useState } from 'react';
+import React, { useEffect, useState, useMemo } from 'react';
 import {
   capitalize,
   createStyles,
@@ -61,6 +61,14 @@ export function CatalogKindHeader(props: CatalogKindHeaderProps) {
   });
   const { updateFilters, queryParameters } = useEntityList();
 
+  const queryParamKind = useMemo(
+    () =>
+      ([queryParameters.kind].flat()[0] ?? initialFilter).toLocaleLowerCase(
+        'en-US',
+      ),
+    [initialFilter, queryParameters],
+  );
+
   const [selectedKind, setSelectedKind] = useState(
     ([queryParameters.kind].flat()[0] ?? initialFilter).toLocaleLowerCase(
       'en-US',
@@ -73,6 +81,14 @@ export function CatalogKindHeader(props: CatalogKindHeaderProps) {
     });
   }, [selectedKind, updateFilters]);
 
+  // Set selected Kind on query parameter updates; this happens at initial page load and from
+  // external updates to the page location.
+  useEffect(() => {
+    if (queryParamKind) {
+      setSelectedKind(queryParamKind);
+    }
+  }, [queryParamKind]);
+
   // Before allKinds is loaded, or when a kind is entered manually in the URL, selectedKind may not
   // be present in allKinds. It should still be shown in the dropdown, but may not have the nice
   // enforced casing from the catalog-backend. This makes a key/value record for the Select options,