[Discover] fix error construction and retrieving status (#8807)

Signed-off-by: Joshua Li <[email protected]>

src/plugins/query_enhancements/common/utils.test.ts

@@ -0,0 +1,28 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { handleFacetError } from './utils';
+
+describe('handleFacetError', () => {
+  const error = new Error('mock-error');
+  (error as any).body = {
+    message: 'test error message',
+  };
+  (error as any).status = '400';
+  it('should throw an error with message from response.data.body.message', () => {
+    const response = {
+      data: error,
+    };
+
+    expect(() => handleFacetError(response)).toThrowError();
+    try {
+      handleFacetError(response);
+    } catch (err: any) {
+      expect(err.message).toBe('test error message');
+      expect(err.name).toBe('400');
+      expect(err.status).toBe('400');
+    }
+  });
+});

src/plugins/query_enhancements/common/utils.ts

@@ -43,7 +43,7 @@ export const removeKeyword = (queryString: string | undefined) => {
 };
 
 export const handleFacetError = (response: any) => {
-  const error = new Error(response.data.body ?? response.data);
+  const error = new Error(response.data.body?.message ?? response.data.body ?? response.data);
   error.name = response.data.status ?? response.status ?? response.data.statusCode;
   (error as any).status = error.name;
   throw error;

src/plugins/query_enhancements/server/routes/index.ts

@@ -92,7 +92,7 @@ export function defineSearchStrategyRouteProvider(logger: Logger, router: IRoute
             error = err;
           }
           return res.custom({
-            statusCode: error.status,
+            statusCode: error.status || err.status,
             body: err.message,
           });
         }