Add selector default support for ActiveDropdown (#2251)

Author: lokanandaprabhu

workspaces/orchestrator/.changeset/active-dropdown-selector-default.md

@@ -0,0 +1,5 @@
+---
+'@red-hat-developer-hub/backstage-plugin-orchestrator-form-widgets': patch
+---
+
+Allow ActiveDropdown fetch:response:default to be a JSONata selector evaluated against the fetch response.

workspaces/orchestrator/docs/orchestratorFormWidgets.md

@@ -23,3 +23,4 @@ export * from './useFetch';
 export * from './useFetchAndEvaluate';
 export * from './applySelector';
 export * from './useProcessingState';
+export * from './resolveDropdownDefault';

workspaces/orchestrator/plugins/orchestrator-form-widgets/src/utils/index.ts

@@ -0,0 +1,38 @@
+/*
+ * Copyright Red Hat, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import { resolveDropdownDefault } from './resolveDropdownDefault';
+
+describe('resolveDropdownDefault', () => {
+  it('uses selector-derived default when it matches a fetched option', async () => {
+    const result = await resolveDropdownDefault({
+      data: { selected: 'b' },
+      values: ['a', 'b'],
+      staticDefault: 'selected',
+    });
+
+    expect(result).toBe('b');
+  });
+
+  it('falls back to the static default when selector evaluation fails', async () => {
+    const result = await resolveDropdownDefault({
+      data: { other: 'value' },
+      values: ['create', 'update'],
+      staticDefault: 'create',
+    });
+
+    expect(result).toBe('create');
+  });
+});

workspaces/orchestrator/plugins/orchestrator-form-widgets/src/utils/resolveDropdownDefault.test.ts

@@ -0,0 +1,55 @@
+/*
+ * Copyright Red Hat, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import { JsonObject } from '@backstage/types';
+
+import { applySelectorString } from './applySelector';
+
+type ResolveDropdownDefaultOptions = {
+  data?: JsonObject;
+  values: string[];
+  staticDefault?: string;
+};
+
+export const resolveDropdownDefault = async ({
+  data,
+  values,
+  staticDefault,
+}: ResolveDropdownDefaultOptions): Promise<string | undefined> => {
+  if (!values || values.length === 0) {
+    return undefined;
+  }
+
+  const hasStaticDefault = typeof staticDefault === 'string';
+  let resolvedDefault: string | undefined;
+
+  if (hasStaticDefault && data) {
+    try {
+      resolvedDefault = await applySelectorString(data, staticDefault);
+    } catch {
+      resolvedDefault = undefined;
+    }
+  }
+
+  if (resolvedDefault && values.includes(resolvedDefault)) {
+    return resolvedDefault;
+  }
+
+  if (hasStaticDefault && values.includes(staticDefault)) {
+    return staticDefault;
+  }
+
+  return values[0];
+};

workspaces/orchestrator/plugins/orchestrator-form-widgets/src/utils/resolveDropdownDefault.ts

@@ -32,6 +32,7 @@ import {
   useRetriggerEvaluate,
   useTemplateUnitEvaluator,
   applySelectorArray,
+  resolveDropdownDefault,
   useProcessingState,
 } from '../utils';
 import { UiProps } from '../uiPropTypes';
@@ -159,33 +160,51 @@ export const ActiveDropdown: Widget<
   );
 
   // Set default value from fetched options
-  // Priority: static default (if valid option) > first fetched option
+  // Priority: selector default (if valid option) > static default (if valid) > first fetched option
   // Note: Static defaults are applied at form initialization level (in OrchestratorForm)
   useEffect(() => {
-    if (
-      !skipInitialValue &&
-      !isChangedByUser &&
-      !value &&
-      values &&
-      values.length > 0
-    ) {
-      // If static default is provided and is a valid option, use it
-      if (hasStaticDefault && values.includes(staticDefault)) {
-        handleChange(staticDefault, false);
-      } else {
-        // Otherwise use the first fetched value
-        handleChange(values[0], false);
+    let isActive = true;
+    const applyDefault = async () => {
+      if (
+        skipInitialValue ||
+        isChangedByUser ||
+        !values ||
+        values.length === 0
+      ) {
+        return;
       }
-    }
+
+      const defaultValue = await resolveDropdownDefault({
+        data,
+        values,
+        staticDefault: staticDefaultValue,
+      });
+
+      if (!isActive || defaultValue === undefined) {
+        return;
+      }
+
+      const shouldApplyDefault =
+        !value || (hasStaticDefault && value === staticDefaultValue);
+      if (shouldApplyDefault && defaultValue !== value) {
+        handleChange(defaultValue, false);
+      }
+    };
+
+    applyDefault();
+
+    return () => {
+      isActive = false;
+    };
   }, [
     handleChange,
     value,
     values,
     isChangedByUser,
-    staticDefault,
     staticDefaultValue,
     hasStaticDefault,
     skipInitialValue,
+    data,
   ]);
 
   const shouldShowFetchError = uiProps['fetch:error:silent'] !== true;