[Enterprise Search] Minor flashAPIMessages update (#77570) (#77629)

* Fix missing export 🤦‍♀️

* Add fallback for http errors without an errors array

- all http error messages should still be expected to contain a message key, so should be a reliable fallback

x-pack/plugins/enterprise_search/public/applications/shared/flash_messages/handle_api_errors.test.ts

@@ -52,6 +52,20 @@ describe('flashAPIErrors', () => {
     ]);
   });
 
+  it('falls back to the basic message for http responses without an errors array', () => {
+    flashAPIErrors({
+      body: {
+        statusCode: 404,
+        error: 'Not Found',
+        message: 'Not Found',
+      },
+    } as any);
+
+    expect(FlashMessagesLogic.actions.setFlashMessages).toHaveBeenCalledWith([
+      { type: 'error', message: 'Not Found' },
+    ]);
+  });
+
   it('displays a generic error message and re-throws non-API errors', () => {
     try {
       flashAPIErrors(Error('whatever') as any);

x-pack/plugins/enterprise_search/public/applications/shared/flash_messages/handle_api_errors.ts

@@ -40,7 +40,7 @@ export const flashAPIErrors = (
 
   const errorFlashMessages: IFlashMessage[] = Array.isArray(error?.body?.attributes?.errors)
     ? error.body!.attributes.errors.map((message) => ({ type: 'error', message }))
-    : [{ type: 'error', message: defaultErrorMessage }];
+    : [{ type: 'error', message: error?.body?.message || defaultErrorMessage }];
 
   if (isQueued) {
     FlashMessagesLogic.actions.setQueuedMessages(errorFlashMessages);

x-pack/plugins/enterprise_search/public/applications/shared/flash_messages/index.ts

@@ -12,3 +12,4 @@ export {
   IFlashMessagesActions,
 } from './flash_messages_logic';
 export { FlashMessagesProvider } from './flash_messages_provider';
+export { flashAPIErrors } from './handle_api_errors';