Chore: Remove several instances of non-strict null usage (#20563)

packages/grafana-runtime/src/services/LocationSrv.ts

@@ -18,8 +18,8 @@ export interface LocationUpdate {
   replace?: boolean;
 }
 
-export type UrlQueryValue = string | number | boolean | string[] | number[] | boolean[];
-export type UrlQueryMap = { [s: string]: UrlQueryValue };
+export type UrlQueryValue = string | number | boolean | string[] | number[] | boolean[] | undefined;
+export type UrlQueryMap = Record<string, UrlQueryValue>;
 
 export interface LocationSrv {
   update(options: LocationUpdate): void;

packages/grafana-ui/src/components/Collapse/Collapse.tsx

@@ -83,7 +83,7 @@ const getStyles = stylesFactory((theme: GrafanaTheme) => ({
 }));
 
 interface Props {
-  isOpen: boolean;
+  isOpen?: boolean;
   label: string;
   loading?: boolean;
   collapsible?: boolean;

packages/grafana-ui/src/components/Graph/Graph.tsx

@@ -14,7 +14,7 @@ export interface GraphProps {
   children?: JSX.Element | JSX.Element[];
   series: GraphSeriesXY[];
   timeRange: TimeRange; // NOTE: we should aim to make `time` a property of the axis, not force it for all graphs
-  timeZone: TimeZone; // NOTE: we should aim to make `time` a property of the axis, not force it for all graphs
+  timeZone?: TimeZone; // NOTE: we should aim to make `time` a property of the axis, not force it for all graphs
   showLines?: boolean;
   showPoints?: boolean;
   showBars?: boolean;
@@ -246,7 +246,7 @@ export class Graph extends PureComponent<GraphProps, GraphState> {
         label: 'Datetime',
         ticks: ticks,
         timeformat: timeFormat(ticks, min, max),
-        timezone: timeZone ? timeZone : DefaultTimeZone,
+        timezone: timeZone ?? DefaultTimeZone,
       },
       yaxes,
       grid: {

packages/grafana-ui/src/components/Logs/LogRows.tsx

@@ -16,7 +16,7 @@ export interface Props extends Themeable {
   logRows?: LogRowModel[];
   deduplicatedRows?: LogRowModel[];
   dedupStrategy: LogsDedupStrategy;
-  highlighterExpressions: string[];
+  highlighterExpressions?: string[];
   showTime: boolean;
   timeZone: TimeZone;
   rowLimit?: number;

packages/grafana-ui/src/components/RefreshPicker/RefreshPicker.tsx

@@ -37,7 +37,7 @@ export interface Props {
 export class RefreshPickerBase extends PureComponent<Props> {
   static offOption = { label: 'Off', value: '' };
   static liveOption = { label: 'Live', value: 'LIVE' };
-  static isLive = (refreshInterval: string): boolean => refreshInterval === RefreshPicker.liveOption.value;
+  static isLive = (refreshInterval?: string): boolean => refreshInterval === RefreshPicker.liveOption.value;
 
   constructor(props: Props) {
     super(props);

public/app/core/logs_model.ts

@@ -42,7 +42,7 @@ export const LogLevelColor = {
 };
 
 const isoDateRegexp = /\d{4}-[01]\d-[0-3]\dT[0-2]\d:[0-5]\d:[0-6]\d[,\.]\d+([+-][0-2]\d:[0-5]\d|Z)/g;
-function isDuplicateRow(row: LogRowModel, other: LogRowModel, strategy: LogsDedupStrategy): boolean {
+function isDuplicateRow(row: LogRowModel, other: LogRowModel, strategy?: LogsDedupStrategy): boolean {
   switch (strategy) {
     case LogsDedupStrategy.exact:
       // Exact still strips dates
@@ -59,7 +59,7 @@ function isDuplicateRow(row: LogRowModel, other: LogRowModel, strategy: LogsDedu
   }
 }
 
-export function dedupLogRows(rows: LogRowModel[], strategy: LogsDedupStrategy): LogRowModel[] {
+export function dedupLogRows(rows: LogRowModel[], strategy?: LogsDedupStrategy): LogRowModel[] {
   if (strategy === LogsDedupStrategy.none) {
     return rows;
   }
@@ -68,7 +68,7 @@ export function dedupLogRows(rows: LogRowModel[], strategy: LogsDedupStrategy):
     const rowCopy = { ...row };
     const previous = result[result.length - 1];
     if (index > 0 && isDuplicateRow(row, previous, strategy)) {
-      previous.duplicates++;
+      previous.duplicates!++;
     } else {
       rowCopy.duplicates = 0;
       result.push(rowCopy);

public/app/core/utils/explore.test.ts

@@ -202,20 +202,20 @@ describe('hasNonEmptyQuery', () => {
 
 describe('hasRefId', () => {
   describe('when called with a null value', () => {
-    it('then it should return null', () => {
+    it('then it should return undefined', () => {
       const input: any = null;
       const result = getValueWithRefId(input);
 
-      expect(result).toBeNull();
+      expect(result).toBeUndefined();
     });
   });
 
   describe('when called with a non object value', () => {
-    it('then it should return null', () => {
+    it('then it should return undefined', () => {
       const input = 123;
       const result = getValueWithRefId(input);
 
-      expect(result).toBeNull();
+      expect(result).toBeUndefined();
     });
   });
 
@@ -249,11 +249,11 @@ describe('hasRefId', () => {
 
 describe('getFirstQueryErrorWithoutRefId', () => {
   describe('when called with a null value', () => {
-    it('then it should return null', () => {
+    it('then it should return undefined', () => {
       const errors: DataQueryError[] = null;
       const result = getFirstQueryErrorWithoutRefId(errors);
 
-      expect(result).toBeNull();
+      expect(result).toBeUndefined();
     });
   });
 

public/app/core/utils/explore.ts

@@ -418,13 +418,9 @@ export const getTimeRangeFromUrl = (range: RawTimeRange, timeZone: TimeZone): Ti
   };
 };
 
-export const getValueWithRefId = (value: any): any | null => {
-  if (!value) {
-    return null;
-  }
-
-  if (typeof value !== 'object') {
-    return null;
+export const getValueWithRefId = (value?: any): any => {
+  if (!value || typeof value !== 'object') {
+    return undefined;
   }
 
   if (value.refId) {
@@ -440,12 +436,12 @@ export const getValueWithRefId = (value: any): any | null => {
     }
   }
 
-  return null;
+  return undefined;
 };
 
-export const getFirstQueryErrorWithoutRefId = (errors: DataQueryError[]) => {
+export const getFirstQueryErrorWithoutRefId = (errors?: DataQueryError[]) => {
   if (!errors) {
-    return null;
+    return undefined;
   }
 
   return errors.filter(error => (error && error.refId ? false : true))[0];
@@ -503,7 +499,7 @@ export enum SortOrder {
   Ascending = 'Ascending',
 }
 
-export const refreshIntervalToSortOrder = (refreshInterval: string) =>
+export const refreshIntervalToSortOrder = (refreshInterval?: string) =>
   RefreshPicker.isLive(refreshInterval) ? SortOrder.Ascending : SortOrder.Descending;
 
 export const sortLogsResult = (logsResult: LogsModel, sortOrder: SortOrder): LogsModel => {

public/app/features/explore/AdHocFilter.tsx

@@ -36,6 +36,11 @@ export const AdHocFilter: React.FunctionComponent<Props> = props => {
 
   const onChange = (changeType: ChangeType) => (item: SelectableValue<string>) => {
     const { onKeyChanged, onValueChanged, onOperatorChanged } = props;
+
+    if (!item.value) {
+      return;
+    }
+
     switch (changeType) {
       case ChangeType.Key:
         onKeyChanged(item.value);
@@ -54,13 +59,13 @@ export const AdHocFilter: React.FunctionComponent<Props> = props => {
   const { keys, initialKey, keysPlaceHolder, initialOperator, values, initialValue, valuesPlaceHolder } = props;
   const operators = ['=', '!='];
   const keysAsOptions = keys ? keys.map(stringToOption) : [];
-  const selectedKey = initialKey ? keysAsOptions.filter(option => option.value === initialKey) : null;
+  const selectedKey = initialKey ? keysAsOptions.filter(option => option.value === initialKey) : undefined;
   const valuesAsOptions = values ? values.map(stringToOption) : [];
-  const selectedValue = initialValue ? valuesAsOptions.filter(option => option.value === initialValue) : null;
+  const selectedValue = initialValue ? valuesAsOptions.filter(option => option.value === initialValue) : undefined;
   const operatorsAsOptions = operators.map(stringToOption);
   const selectedOperator = initialOperator
     ? operatorsAsOptions.filter(option => option.value === initialOperator)
-    : null;
+    : undefined;
 
   return (
     <div className={cx([styles.keyValueContainer])}>

public/app/features/explore/AdHocFilterField.test.tsx

@@ -174,11 +174,11 @@ describe('AdHocFilterField', () => {
           const { instance } = setup();
           const pairs: KeyValuePair[] = [];
           const index = 0;
-          const key: string = undefined;
+          const key: undefined = undefined;
           const keys: string[] = ['key 1', 'key 2'];
-          const value: string = undefined;
-          const values: string[] = undefined;
-          const operator: string = undefined;
+          const value: undefined = undefined;
+          const values: undefined = undefined;
+          const operator: undefined = undefined;
 
           const result = instance.updatePairs(pairs, index, { key, keys, value, values, operator });
 

public/app/features/explore/AdHocFilterField.tsx

@@ -131,7 +131,7 @@ export class AdHocFilterField<
         return allPairs;
       }
       return allPairs.concat(pair);
-    }, []);
+    }, [] as KeyValuePair[]);
 
     this.setState({ pairs });
   };

public/app/features/explore/ErrorContainer.tsx

@@ -4,7 +4,7 @@ import { FadeIn } from 'app/core/components/Animations/FadeIn';
 import { getFirstQueryErrorWithoutRefId, getValueWithRefId } from 'app/core/utils/explore';
 
 interface Props {
-  queryErrors: DataQueryError[];
+  queryErrors?: DataQueryError[];
 }
 
 export const ErrorContainer: FunctionComponent<Props> = props => {

public/app/features/explore/Explore.tsx

@@ -203,9 +203,10 @@ export class Explore extends React.PureComponent<ExploreProps> {
 
   onModifyQueries = (action: any, index?: number) => {
     const { datasourceInstance } = this.props;
-    if (datasourceInstance && datasourceInstance.modifyQuery) {
-      const modifier = (queries: DataQuery, modification: any) => datasourceInstance.modifyQuery(queries, modification);
-      this.props.modifyQueries(this.props.exploreId, action, index, modifier);
+    if (datasourceInstance?.modifyQuery) {
+      const modifier = (queries: DataQuery, modification: any) =>
+        datasourceInstance.modifyQuery!(queries, modification);
+      this.props.modifyQueries(this.props.exploreId, action, modifier, index);
     }
   };
 
@@ -277,7 +278,7 @@ export class Explore extends React.PureComponent<ExploreProps> {
         {datasourceInstance && (
           <div className="explore-container">
             <QueryRows exploreEvents={this.exploreEvents} exploreId={exploreId} queryKeys={queryKeys} />
-            <ErrorContainer queryErrors={[queryResponse.error]} />
+            <ErrorContainer queryErrors={queryResponse.error ? [queryResponse.error] : undefined} />
             <AutoSizer onResize={this.onResize} disableHeight>
               {({ width }) => {
                 if (width === 0) {
@@ -287,7 +288,7 @@ export class Explore extends React.PureComponent<ExploreProps> {
                 return (
                   <main className={`m-t-2 ${styles.logsMain}`} style={{ width }}>
                     <ErrorBoundaryAlert>
-                      {showingStartPage && (
+                      {showingStartPage && StartPage && (
                         <div className="grafana-info-box grafana-info-box--max-lg">
                           <StartPage
                             onClickExample={this.onClickExample}
@@ -377,7 +378,7 @@ function mapStateToProps(state: StoreState, { exploreId }: ExploreProps): Partia
   const initialQueries: DataQuery[] = ensureQueriesMemoized(queries);
   const initialRange = urlRange ? getTimeRangeFromUrlMemoized(urlRange, timeZone).raw : DEFAULT_RANGE;
 
-  let newMode: ExploreMode;
+  let newMode: ExploreMode | undefined;
 
   if (supportedModes.length) {
     const urlModeIsValid = supportedModes.includes(urlMode);
@@ -391,7 +392,7 @@ function mapStateToProps(state: StoreState, { exploreId }: ExploreProps): Partia
       newMode = supportedModes[0];
     }
   } else {
-    newMode = [ExploreMode.Metrics, ExploreMode.Logs].includes(urlMode) ? urlMode : null;
+    newMode = [ExploreMode.Metrics, ExploreMode.Logs].includes(urlMode) ? urlMode : undefined;
   }
 
   const initialUI = ui || DEFAULT_UI_STATE;

public/app/features/explore/ExploreGraphPanel.tsx

@@ -39,17 +39,17 @@ const getStyles = (theme: GrafanaTheme) => ({
 });
 
 interface Props extends Themeable {
-  series: GraphSeriesXY[];
+  series?: GraphSeriesXY[];
   width: number;
   absoluteRange: AbsoluteTimeRange;
-  loading: boolean;
+  loading?: boolean;
   showPanel: boolean;
   showBars: boolean;
   showLines: boolean;
   isStacked: boolean;
-  showingGraph: boolean;
-  showingTable: boolean;
-  timeZone: TimeZone;
+  showingGraph?: boolean;
+  showingTable?: boolean;
+  timeZone?: TimeZone;
   onUpdateTimeRange: (absoluteRange: AbsoluteTimeRange) => void;
   onToggleGraph?: (showingGraph: boolean) => void;
   onHiddenSeriesChanged?: (hiddenSeries: string[]) => void;
@@ -75,7 +75,7 @@ class UnThemedExploreGraphPanel extends PureComponent<Props, State> {
   onClickGraphButton = () => {
     const { onToggleGraph, showingGraph } = this.props;
     if (onToggleGraph) {
-      onToggleGraph(showingGraph);
+      onToggleGraph(showingGraph ?? false);
     }
   };
 

public/app/features/explore/ExploreTimeControls.tsx

@@ -73,7 +73,7 @@ export class ExploreTimeControls extends Component<Props> {
 
   render() {
     const { range, timeZone, splitted, syncedTimes, onChangeTimeSync, hideText } = this.props;
-    const timeSyncButton = splitted ? <TimeSyncButton onClick={onChangeTimeSync} isSynced={syncedTimes} /> : null;
+    const timeSyncButton = splitted ? <TimeSyncButton onClick={onChangeTimeSync} isSynced={syncedTimes} /> : undefined;
     const timePickerCommonProps = {
       value: range,
       onChange: this.onChangeTimePicker,

public/app/features/explore/ExploreToolbar.tsx

@@ -54,18 +54,18 @@ interface StateProps {
   loading: boolean;
   range: TimeRange;
   timeZone: TimeZone;
-  selectedDatasource: DataSourceSelectItem;
+  selectedDatasource?: DataSourceSelectItem;
   splitted: boolean;
   syncedTimes: boolean;
-  refreshInterval: string;
+  refreshInterval?: string;
   supportedModes: ExploreMode[];
   selectedMode: ExploreMode;
   hasLiveOption: boolean;
   isLive: boolean;
   isPaused: boolean;
-  originPanelId: number;
+  originPanelId?: number;
   queries: DataQuery[];
-  datasourceLoading: boolean | null;
+  datasourceLoading?: boolean;
   containerWidth: number;
 }
 
@@ -163,7 +163,7 @@ export class UnConnectedExploreToolbar extends PureComponent<Props> {
     } = this.props;
 
     const styles = getStyles();
-    const originDashboardIsEditable = Number.isInteger(originPanelId);
+    const originDashboardIsEditable = originPanelId && Number.isInteger(originPanelId);
     const panelReturnClasses = classNames('btn', 'navbar-button', {
       'btn--radius-right-0': originDashboardIsEditable,
       'navbar-button navbar-button--border-right-0': originDashboardIsEditable,
@@ -234,7 +234,7 @@ export class UnConnectedExploreToolbar extends PureComponent<Props> {
               </div>
             ) : null}
 
-            {Number.isInteger(originPanelId) && !splitted && (
+            {originPanelId && Number.isInteger(originPanelId) && !splitted && (
               <div className="explore-toolbar-content-item">
                 <Tooltip content={'Return to panel'} placement="bottom">
                   <button className={panelReturnClasses} onClick={() => this.returnToPanel()}>

public/app/features/explore/LiveLogs.tsx

@@ -63,7 +63,7 @@ interface State {
 }
 
 class LiveLogs extends PureComponent<Props, State> {
-  private liveEndDiv: HTMLDivElement = null;
+  private liveEndDiv: HTMLDivElement | null = null;
   private scrollContainerRef = React.createRef<HTMLDivElement>();
   private lastScrollPos: number | null = null;
 
@@ -77,7 +77,7 @@ class LiveLogs extends PureComponent<Props, State> {
   componentDidUpdate(prevProps: Props) {
     if (!prevProps.isPaused && this.props.isPaused) {
       // So we paused the view and we changed the content size, but we want to keep the relative offset from the bottom.
-      if (this.lastScrollPos) {
+      if (this.lastScrollPos && this.scrollContainerRef.current) {
         // There is last scroll pos from when user scrolled up a bit so go to that position.
         const { clientHeight, scrollHeight } = this.scrollContainerRef.current;
         const scrollTop = scrollHeight - (this.lastScrollPos + clientHeight);
@@ -123,7 +123,7 @@ class LiveLogs extends PureComponent<Props, State> {
 
   rowsToRender = () => {
     const { isPaused } = this.props;
-    let rowsToRender: LogRowModel[] = this.state.logRowsToRender;
+    let { logRowsToRender: rowsToRender = [] } = this.state;
     if (!isPaused) {
       // A perf optimisation here. Show just 100 rows when streaming and full length when the streaming is paused.
       rowsToRender = rowsToRender.slice(-100);

public/app/features/explore/Logs.tsx

@@ -37,7 +37,7 @@ interface Props {
   dedupedRows?: LogRowModel[];
 
   width: number;
-  highlighterExpressions: string[];
+  highlighterExpressions?: string[];
   loading: boolean;
   absoluteRange: AbsoluteTimeRange;
   timeZone: TimeZone;

public/app/features/explore/LogsContainer.tsx

@@ -30,7 +30,7 @@ import { LiveTailControls } from './useLiveTailControls';
 import { getLinksFromLogsField } from '../panel/panellinks/linkSuppliers';
 
 interface LogsContainerProps {
-  datasourceInstance: DataSourceApi | null;
+  datasourceInstance?: DataSourceApi;
   exploreId: ExploreId;
   loading: boolean;
 
@@ -80,7 +80,7 @@ export class LogsContainer extends PureComponent<LogsContainerProps> {
   getLogRowContext = async (row: LogRowModel, options?: any): Promise<any> => {
     const { datasourceInstance } = this.props;
 
-    if (datasourceInstance) {
+    if (datasourceInstance?.getLogRowContext) {
       return datasourceInstance.getLogRowContext(row, options);
     }
 

public/app/features/explore/QueryEditor.tsx

@@ -45,13 +45,13 @@ export default class QueryEditor extends PureComponent<QueryEditorProps, any> {
         target,
         refresh: () => {
           setTimeout(() => {
-            this.props.onQueryChange(target);
-            this.props.onExecuteQuery();
+            this.props.onQueryChange?.(target);
+            this.props.onExecuteQuery?.();
           }, 1);
         },
         onQueryChange: () => {
           setTimeout(() => {
-            this.props.onQueryChange(target);
+            this.props.onQueryChange?.(target);
           }, 1);
         },
         events: exploreEvents,
@@ -64,8 +64,8 @@ export default class QueryEditor extends PureComponent<QueryEditorProps, any> {
     this.angularScope = scopeProps.ctrl;
 
     setTimeout(() => {
-      this.props.onQueryChange(target);
-      this.props.onExecuteQuery();
+      this.props.onQueryChange?.(target);
+      this.props.onExecuteQuery?.();
     }, 1);
   }
 

public/app/features/explore/QueryRow.tsx

@@ -134,12 +134,12 @@ export class QueryRow extends PureComponent<QueryRowProps, QueryRowState> {
     const queryErrors = queryResponse.error && queryResponse.error.refId === query.refId ? [queryResponse.error] : [];
     let QueryField;
 
-    if (mode === ExploreMode.Metrics && datasourceInstance.components.ExploreMetricsQueryField) {
+    if (mode === ExploreMode.Metrics && datasourceInstance.components?.ExploreMetricsQueryField) {
       QueryField = datasourceInstance.components.ExploreMetricsQueryField;
-    } else if (mode === ExploreMode.Logs && datasourceInstance.components.ExploreLogsQueryField) {
+    } else if (mode === ExploreMode.Logs && datasourceInstance.components?.ExploreLogsQueryField) {
       QueryField = datasourceInstance.components.ExploreLogsQueryField;
     } else {
-      QueryField = datasourceInstance.components.ExploreQueryField;
+      QueryField = datasourceInstance.components?.ExploreQueryField;
     }
 
     return (

public/app/features/explore/QueryRowActions.tsx

@@ -2,7 +2,7 @@ import React from 'react';
 
 export type Props = {
   canToggleEditorModes: boolean;
-  isDisabled: boolean;
+  isDisabled?: boolean;
   isNotStarted: boolean;
   onClickToggleEditorMode: () => void;
   onClickToggleDisabled: () => void;

public/app/features/explore/RunButton.tsx

@@ -21,7 +21,7 @@ type Props = {
   splitted: boolean;
   loading: boolean;
   onRun: () => void;
-  refreshInterval: string;
+  refreshInterval?: string;
   onChangeRefreshInterval: (interval: string) => void;
   showDropdown: boolean;
 };

public/app/features/explore/Table.tsx

@@ -28,7 +28,7 @@ export default class Table extends PureComponent<TableProps> {
           if (link.className === 'link') {
             const columnKey = column.Header().props.title;
             const rowValue = rowInfo.row[columnKey];
-            this.props.onClickCell(columnKey, rowValue);
+            this.props.onClickCell?.(columnKey, rowValue);
           }
         }
       },

public/app/features/explore/state/actionTypes.ts

@@ -118,7 +118,7 @@ export interface LoadDatasourceReadyPayload {
 export interface ModifyQueriesPayload {
   exploreId: ExploreId;
   modification: QueryFixAction;
-  index: number;
+  index?: number;
   modifier: (query: DataQuery, modification: QueryFixAction) => DataQuery;
 }
 

public/app/features/explore/state/actions.ts

@@ -162,7 +162,7 @@ export function changeQuery(
   exploreId: ExploreId,
   query: DataQuery,
   index: number,
-  override: boolean
+  override = false
 ): ThunkResult<void> {
   return (dispatch, getState) => {
     // Null query means reset
@@ -389,8 +389,8 @@ export function loadDatasource(exploreId: ExploreId, instance: DataSourceApi, or
 export function modifyQueries(
   exploreId: ExploreId,
   modification: QueryFixAction,
-  index: number,
-  modifier: any
+  modifier: any,
+  index?: number
 ): ThunkResult<void> {
   return dispatch => {
     dispatch(modifyQueriesAction({ exploreId, modification, index, modifier }));

public/app/features/explore/state/selectors.test.ts

@@ -59,7 +59,7 @@ const state: any = {
 describe('Deduplication selector', () => {
   it('returns the same rows if no deduplication', () => {
     const dedups = deduplicatedRowsSelector(state as ExploreItemState);
-    expect(dedups.length).toBe(11);
+    expect(dedups?.length).toBe(11);
     expect(dedups).toBe(state.logsResult.rows);
   });
 
@@ -68,7 +68,7 @@ describe('Deduplication selector', () => {
       ...state,
       dedupStrategy: LogsDedupStrategy.numbers,
     } as ExploreItemState);
-    expect(dedups.length).toBe(2);
+    expect(dedups?.length).toBe(2);
     expect(dedups).not.toBe(state.logsResult.rows);
   });
 
@@ -77,7 +77,7 @@ describe('Deduplication selector', () => {
       ...state,
       hiddenLogLevels: [LogLevel.debug],
     } as ExploreItemState);
-    expect(dedups.length).toBe(2);
+    expect(dedups?.length).toBe(2);
     expect(dedups).not.toBe(state.logsResult.rows);
 
     dedups = deduplicatedRowsSelector({
@@ -86,7 +86,7 @@ describe('Deduplication selector', () => {
       hiddenLogLevels: [LogLevel.debug],
     } as ExploreItemState);
 
-    expect(dedups.length).toBe(2);
+    expect(dedups?.length).toBe(2);
     expect(dedups).not.toBe(state.logsResult.rows);
   });
 });

public/app/features/explore/utils/ResultProcessor.ts

@@ -14,7 +14,7 @@ export class ResultProcessor {
     private timeZone: TimeZone
   ) {}
 
-  getGraphResult(): GraphSeriesXY[] {
+  getGraphResult(): GraphSeriesXY[] | null {
     if (this.state.mode !== ExploreMode.Metrics) {
       return null;
     }
@@ -34,7 +34,7 @@ export class ResultProcessor {
     );
   }
 
-  getTableResult(): TableModel {
+  getTableResult(): TableModel | null {
     if (this.state.mode !== ExploreMode.Metrics) {
       return null;
     }
@@ -78,7 +78,7 @@ export class ResultProcessor {
     return mergeTablesIntoModel(new TableModel(), ...tables);
   }
 
-  getLogsResult(): LogsModel {
+  getLogsResult(): LogsModel | null {
     if (this.state.mode !== ExploreMode.Logs) {
       return null;
     }

public/app/types/explore.ts

@@ -65,7 +65,7 @@ export interface ExploreItemState {
   /**
    * Datasource instance that has been selected. Datasource-specific logic can be run on this object.
    */
-  datasourceInstance: DataSourceApi | null;
+  datasourceInstance?: DataSourceApi;
   /**
    * Current data source name or null if default
    */
@@ -73,7 +73,7 @@ export interface ExploreItemState {
   /**
    * True if the datasource is loading. `null` if the loading has not started yet.
    */
-  datasourceLoading: boolean | null;
+  datasourceLoading?: boolean;
   /**
    * True if there is no datasource to be selected.
    */