Runtime: Add provider and access hook for location service (#90759)

.betterer.results

@@ -514,7 +514,7 @@ exports[`better eslint`] = {
       [0, 0, 0, "Unexpected any. Specify a different type.", "2"],
       [0, 0, 0, "Unexpected any. Specify a different type.", "3"]
     ],
-    "packages/grafana-runtime/src/services/LocationService.ts:5381": [
+    "packages/grafana-runtime/src/services/LocationService.tsx:5381": [
       [0, 0, 0, "Unexpected any. Specify a different type.", "0"],
       [0, 0, 0, "Unexpected any. Specify a different type.", "1"],
       [0, 0, 0, "Unexpected any. Specify a different type.", "2"],

packages/grafana-runtime/src/services/LocationService.test.tsx

@@ -1,4 +1,6 @@
-import { locationService } from './LocationService';
+import { renderHook } from '@testing-library/react-hooks';
+
+import { locationService, HistoryWrapper, useLocationService, LocationServiceProvider } from './LocationService';
 
 describe('LocationService', () => {
   describe('getSearchObject', () => {
@@ -51,4 +53,15 @@ describe('LocationService', () => {
       });
     });
   });
+
+  describe('hook access', () => {
+    it('can set and access service from a context', () => {
+      const locationServiceLocal = new HistoryWrapper();
+      const wrapper: React.FunctionComponent<{ children: React.ReactNode }> = ({ children }) => (
+        <LocationServiceProvider service={locationServiceLocal}>{children}</LocationServiceProvider>
+      );
+      const hookResult = renderHook(() => useLocationService(), { wrapper });
+      expect(hookResult.result.current).toBe(locationServiceLocal);
+    });
+  });
 });

packages/grafana-runtime/src/services/LocationService.tsx

@@ -1,4 +1,5 @@
 import * as H from 'history';
+import React, { useContext } from 'react';
 
 import { deprecationWarning, UrlQueryMap, urlUtil } from '@grafana/data';
 import { attachDebugger, createLogger } from '@grafana/ui';
@@ -162,3 +163,21 @@ export const navigationLogger = navigationLog.logger;
 
 // For debugging purposes the location service is attached to global _debug variable
 attachDebugger('location', locationService, navigationLog);
+
+// Simple context so the location service can be used without being a singleton
+const LocationServiceContext = React.createContext<LocationService | undefined>(undefined);
+
+export function useLocationService(): LocationService {
+  const service = useContext(LocationServiceContext);
+  if (!service) {
+    throw new Error('useLocationService must be used within a LocationServiceProvider');
+  }
+  return service;
+}
+
+export const LocationServiceProvider: React.FC<{ service: LocationService; children: React.ReactNode }> = ({
+  service,
+  children,
+}) => {
+  return <LocationServiceContext.Provider value={service}>{children}</LocationServiceContext.Provider>;
+};

public/app/AppWrapper.tsx

@@ -4,7 +4,13 @@ import { Provider } from 'react-redux';
 import { Router, Redirect, Switch, RouteComponentProps } from 'react-router-dom';
 import { CompatRouter, CompatRoute } from 'react-router-dom-v5-compat';
 
-import { config, locationService, navigationLogger, reportInteraction } from '@grafana/runtime';
+import {
+  config,
+  locationService,
+  LocationServiceProvider,
+  navigationLogger,
+  reportInteraction,
+} from '@grafana/runtime';
 import { ErrorBoundaryAlert, GlobalStyles, ModalRoot, PortalContainer, Stack } from '@grafana/ui';
 import { getAppRoutes } from 'app/routes/routes';
 import { store } from 'app/store/store';
@@ -104,29 +110,31 @@ export class AppWrapper extends Component<AppWrapperProps, AppWrapperState> {
                 options={{ enableHistory: true, callbacks: { onSelectAction: commandPaletteActionSelected } }}
               >
                 <Router history={locationService.getHistory()}>
-                  <CompatRouter>
-                    <ModalsContextProvider>
-                      <GlobalStyles />
-                      <div className="grafana-app">
-                        <AppChrome>
-                          <AngularRoot />
-                          <AppNotificationList />
-                          <Stack gap={0} grow={1} direction="column">
-                            {pageBanners.map((Banner, index) => (
-                              <Banner key={index.toString()} />
+                  <LocationServiceProvider service={locationService}>
+                    <CompatRouter>
+                      <ModalsContextProvider>
+                        <GlobalStyles />
+                        <div className="grafana-app">
+                          <AppChrome>
+                            <AngularRoot />
+                            <AppNotificationList />
+                            <Stack gap={0} grow={1} direction="column">
+                              {pageBanners.map((Banner, index) => (
+                                <Banner key={index.toString()} />
+                              ))}
+                              {ready && this.renderRoutes()}
+                            </Stack>
+                            {bodyRenderHooks.map((Hook, index) => (
+                              <Hook key={index.toString()} />
                             ))}
-                            {ready && this.renderRoutes()}
-                          </Stack>
-                          {bodyRenderHooks.map((Hook, index) => (
-                            <Hook key={index.toString()} />
-                          ))}
-                        </AppChrome>
-                      </div>
-                      <LiveConnectionWarning />
-                      <ModalRoot />
-                      <PortalContainer />
-                    </ModalsContextProvider>
-                  </CompatRouter>
+                          </AppChrome>
+                        </div>
+                        <LiveConnectionWarning />
+                        <ModalRoot />
+                        <PortalContainer />
+                      </ModalsContextProvider>
+                    </CompatRouter>
+                  </LocationServiceProvider>
                 </Router>
               </KBarProvider>
             </ThemeProvider>