fix(orchestrator-form-widgets): avoid ActiveTextInput crash when fetch:response:value resolves to missing key

workspaces/orchestrator/.changeset/active-textinput-missing-selector.md

@@ -0,0 +1,5 @@
+---
+'@red-hat-developer-hub/backstage-plugin-orchestrator-form-widgets': patch
+---
+
+Avoid hard failures in ActiveTextInput when `fetch:response:value` points to a missing response property. If JSONata resolves to `undefined` or `null`, treat it as an empty string so retriggered dynamic selector edits do not break the form UI.

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

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { applySelectorArray } from './applySelector';
+import { applySelectorArray, applySelectorString } from './applySelector';
 import { JsonObject } from '@backstage/types';
 
 describe('applySelectorArray', () => {
@@ -258,6 +258,40 @@ describe('applySelectorArray', () => {
   });
 });
 
+describe('applySelectorString', () => {
+  const data: JsonObject = { status: 'UP', nested: { name: 'x' } };
+
+  it('returns string when selector evaluates to a string', async () => {
+    await expect(applySelectorString(data, 'status')).resolves.toBe('UP');
+  });
+
+  it('throws when selector is missing and emptyStringWhenMissing is false', async () => {
+    await expect(applySelectorString(data, 'doesNotExist')).rejects.toThrow(
+      'Unexpected result of "doesNotExist" selector, expected string type',
+    );
+  });
+
+  it('returns empty string when selector is missing and emptyStringWhenMissing is true', async () => {
+    await expect(applySelectorString(data, 'doesNotExist', true)).resolves.toBe(
+      '',
+    );
+  });
+
+  it('returns empty string when JSONata yields null and emptyStringWhenMissing is true', async () => {
+    const withNull: JsonObject = { absent: null };
+    await expect(applySelectorString(withNull, 'absent', true)).resolves.toBe(
+      '',
+    );
+  });
+
+  it('still throws for non-string non-nullish when emptyStringWhenMissing is true', async () => {
+    const withNum: JsonObject = { n: 42 };
+    await expect(applySelectorString(withNum, 'n', true)).rejects.toThrow(
+      'expected string type',
+    );
+  });
+});
+
 describe('applySelectorArray - complex queries', () => {
   it('handles complex queries', async () => {
     const data = [

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

@@ -46,6 +46,7 @@ export const applySelectorArray = async (
 export const applySelectorString = async (
   data: JsonObject,
   selector: string,
+  emptyStringWhenMissing: boolean = false,
 ): Promise<string> => {
   const expression = jsonata(selector);
   const value = await expression.evaluate(data);
@@ -54,6 +55,10 @@ export const applySelectorString = async (
     return value;
   }
 
+  if (emptyStringWhenMissing && (value === undefined || value === null)) {
+    return '';
+  }
+
   throw new Error(
     `Unexpected result of "${selector}" selector, expected string type. Value "${JSON.stringify(value)}"`,
   );

workspaces/orchestrator/plugins/orchestrator-form-widgets/src/widgets/ActiveTextInput.tsx

@@ -153,6 +153,7 @@ export const ActiveTextInput: Widget<
           const fetchedValue = await applySelectorString(
             data,
             resolvedSelector,
+            true,
           );
 
           if (