fix: Makes query fields nullable

This reflects observed behavior in Grafana operation

Author: NeedleInAJayStack

src/components/HaystackQueryTypeSelector.tsx

@@ -5,7 +5,7 @@ import { DataSource, queryTypes } from '../datasource';
 
 export interface HaystackQueryTypeSelectorProps {
   datasource: DataSource | null;
-  type: string;
+  type?: string;
   refId: string;
   onChange: (type: string) => void;
 }
@@ -16,7 +16,7 @@ export function HaystackQueryTypeSelector({ datasource, type, refId, onChange }:
   };
 
   const queryTypeDefault = queryTypes[0];
-  function queryTypeFromValue(value: string): QueryType | null {
+  function queryTypeFromValue(value?: string): QueryType | null {
     return queryTypes.find((queryType) => queryType.value === value) ?? null;
   }
 

src/components/VariableQueryEditor.tsx

@@ -22,13 +22,13 @@ export const VariableQueryEditor: React.FC<VariableQueryProps> = ({ onChange, qu
     let type = query.type;
     let queryCmd = "";
     if (query.type === "eval") {
-      queryCmd = query.eval
+      queryCmd = query.eval ?? "";
     } else if (query.type === "hisRead") {
-      queryCmd = query.hisRead
+      queryCmd = query.hisRead ?? "";
     } else if (query.type === "hisReadFilter") {
-      queryCmd = query.hisReadFilter
+      queryCmd = query.hisReadFilter ?? "";
     } else if (query.type === "read") {
-      queryCmd = query.read
+      queryCmd = query.read ?? "";
     }
     let column = "none";
     if (query.column !== undefined && query.column !== '') {

src/types.ts

@@ -2,11 +2,11 @@ import { DataSourceJsonData, SelectableValue } from '@grafana/data';
 import { DataQuery } from '@grafana/schema';
 
 export interface HaystackQuery extends DataQuery {
-  type: string; // Defines the type of query that should be executed
-  eval: string;
-  hisRead: string;
-  hisReadFilter: string;
-  read: string;
+  type?: string; // Defines the type of query that should be executed
+  eval?: string;
+  hisRead?: string;
+  hisReadFilter?: string;
+  read?: string;
 }
 
 // OpsQuery is a query that is used to get the available ops from the datasource.