Fix showing connection errors

Author: nineinchnick

src/datasource.test.ts

@@ -54,8 +54,8 @@ describe('Trino datasource', () => {
 
       const ds = new DataSource({ name: '', id: 0, jsonData: {} } as any);
       const result = await ds.testDatasource();
-      expect(result.status).toEqual(400);
-      expect(result.message).toEqual('Query error: 400 Bad Request');
+      expect(result.status).toEqual("error");
+      expect(result.message).toEqual('Query error: Bad Request');
     });
   });
 });

src/datasource.ts

@@ -1,5 +1,5 @@
 import { DataSourceInstanceSettings, ScopedVars } from '@grafana/data';
-import { DataSourceWithBackend, getBackendSrv, getTemplateSrv, toDataQueryError } from '@grafana/runtime';
+import { DataSourceWithBackend, getBackendSrv, getTemplateSrv } from '@grafana/runtime';
 import { TrinoDataSourceOptions, TrinoQuery } from './types';
 import { TrinoDataVariableSupport } from './variable';
 import { lastValueFrom, of } from 'rxjs';
@@ -40,7 +40,10 @@ export class DataSource extends DataSourceWithBackend<TrinoQuery, TrinoDataSourc
         .pipe(
           mapTo({ status: 'success', message: 'Database Connection OK' }),
           catchError((err) => {
-            return of(toDataQueryError(err));
+            return of({
+              status: 'error',
+              message: err.error ? err.error : (err.statusText ? ("Query error: " + err.statusText) : "Error connecting to Trino"),
+            });
           })
         )
     );