Load max revision ID on start (#485)

* Load max revision ID on start

* Update revision ID upon mounting MapApp

app/src/api/controllers/buildingController.ts

@@ -135,6 +135,15 @@ const updateBuildingLikeById = asyncController(async (req: express.Request, res:
     }
 });
 
+const getLatestRevisionId = asyncController(async (req: express.Request, res: express.Response) => {
+    try {
+        const revisionId = await buildingService.getLatestRevisionId();
+        res.send({latestRevisionId: revisionId});
+    } catch(error) {
+        res.send({ error: 'Database error' });
+    }
+});
+
 export default {
     getBuildingsByLocation,
     getBuildingsByReference,
@@ -142,5 +151,6 @@ export default {
     updateBuildingById,
     getBuildingUPRNsById,
     getBuildingLikeById,
-    updateBuildingLikeById
+    updateBuildingLikeById,
+    getLatestRevisionId
 };

app/src/api/routes/buildingsRouter.ts

@@ -14,6 +14,8 @@ router.get('/locate', buildingController.getBuildingsByLocation);
 // GET buildings by reference (UPRN/TOID or other identifier)
 router.get('/reference', buildingController.getBuildingsByReference);
 
+router.get('/revision', buildingController.getLatestRevisionId);
+
 router.route('/:building_id.json')
     // GET individual building
     .get(buildingController.getBuildingById)

app/src/api/services/building.ts

@@ -19,6 +19,19 @@ const serializable = new TransactionMode({
     readOnly: false
 });
 
+async function getLatestRevisionId() {
+    try {
+        const data = await db.oneOrNone(
+            `SELECT MAX(log_id) from logs`
+        );
+        return data == undefined ? undefined : data.max;
+    } catch(err) {
+        console.error(err);
+        return undefined;
+    }
+}
+
+
 async function queryBuildingsAtPoint(lng: number, lat: number) {
     try {
         return await db.manyOrNone(
@@ -412,5 +425,6 @@ export {
     getBuildingUPRNsById,
     saveBuilding,
     likeBuilding,
-    unlikeBuilding
+    unlikeBuilding,
+    getLatestRevisionId
 };

app/src/client.tsx

@@ -12,7 +12,12 @@ const data = (window as any).__PRELOADED_STATE__; // TODO: remove any
 
 hydrate(
     <BrowserRouter>
-        <App user={data.user} building={data.building} building_like={data.building_like} />
+        <App
+            user={data.user}
+            building={data.building}
+            building_like={data.building_like}
+            revisionId={data.latestRevisionId}
+        />
     </BrowserRouter>,
     document.getElementById('root')
 );

app/src/frontend/app.test.tsx

@@ -9,7 +9,7 @@ describe('<App />', () => {
         const div = document.createElement('div');
         ReactDOM.render(
             <MemoryRouter>
-                <App />
+                <App revisionId={0} />
             </MemoryRouter>,
             div
         );

app/src/frontend/app.tsx

@@ -28,6 +28,7 @@ interface AppProps {
     user?: any;
     building?: any;
     building_like?: boolean;
+    revisionId: number;
 }
 
 /**
@@ -120,6 +121,7 @@ class App extends React.Component<AppProps, any> { // TODO: add proper types
                         building={this.props.building}
                         building_like={this.props.building_like}
                         user={this.state.user}
+                        revisionId={this.props.revisionId}
                     />
                 )} />
                 <Route component={NotFound} />

app/src/frontend/map-app.tsx

@@ -20,6 +20,7 @@ interface MapAppProps extends RouteComponentProps<MapAppRouteParams> {
     building: any;
     building_like: boolean;
     user: any;
+    revisionId: number;
 }
 
 interface MapAppState {
@@ -40,12 +41,9 @@ class MapApp extends React.Component<MapAppProps, MapAppState> {
     constructor(props: Readonly<MapAppProps>) {
         super(props);
 
-        // set building revision id, default 0
-        const rev = props.building != undefined ? +props.building.revision_id : 0;
-
         this.state = {
             category: this.getCategory(props.match.params.category),
-            revision_id: rev,
+            revision_id: props.revisionId || 0,
             building: props.building,
             building_like: props.building_like
         };
@@ -62,6 +60,27 @@ class MapApp extends React.Component<MapAppProps, MapAppState> {
         }
     }
 
+    componentDidMount() {
+        this.fetchLatestRevision();
+    }
+
+    async fetchLatestRevision() {
+        try {
+            const res = await fetch(`/api/buildings/revision`, {
+                method: 'GET',
+                headers: {
+                    'Content-Type': 'application/json'
+                },
+                credentials: 'same-origin'
+            });
+            const data = await res.json();
+            
+            this.increaseRevision(data.latestRevisionId);
+        } catch(error) {
+            console.error(error);
+        }
+    }
+
     getCategory(category: string) {
         if (category === 'categories') return undefined;
 
@@ -199,6 +218,7 @@ class MapApp extends React.Component<MapAppProps, MapAppState> {
     }
 
     render() {
+        console.log(this.state.revision_id);
         const mode = this.props.match.params.mode || 'basic';
 
         let category = this.state.category || 'age';

app/src/frontendRoute.tsx

@@ -12,7 +12,8 @@ import { getUserById } from './api/services/user';
 import {
     getBuildingById,
     getBuildingLikeById,
-    getBuildingUPRNsById
+    getBuildingUPRNsById,
+    getLatestRevisionId
 } from './api/services/building';
 
 
@@ -36,8 +37,9 @@ function frontendRoute(req: express.Request, res: express.Response) {
         userId ? getUserById(userId) : undefined,
         isBuilding ? getBuildingById(buildingId) : undefined,
         isBuilding ? getBuildingUPRNsById(buildingId) : undefined,
-        (isBuilding && userId) ? getBuildingLikeById(buildingId, userId) : false
-    ]).then(function ([user, building, uprns, buildingLike]) {
+        (isBuilding && userId) ? getBuildingLikeById(buildingId, userId) : false,
+        getLatestRevisionId()
+    ]).then(function ([user, building, uprns, buildingLike, latestRevisionId]) {
         if (isBuilding && typeof (building) === 'undefined') {
             context.status = 404;
         }
@@ -47,12 +49,14 @@ function frontendRoute(req: express.Request, res: express.Response) {
         if (data.building != null) {
             data.building.uprns = uprns;
         }
+        data.latestRevisionId = latestRevisionId;
         renderHTML(context, data, req, res);
     }).catch(error => {
         console.error(error);
         data.user = undefined;
         data.building = undefined;
         data.building_like = undefined;
+        data.latestRevisionId = 0;
         context.status = 500;
         renderHTML(context, data, req, res);
     });
@@ -61,7 +65,12 @@ function frontendRoute(req: express.Request, res: express.Response) {
 function renderHTML(context, data, req, res) {
     const markup = renderToString(
         <StaticRouter context={context} location={req.url}>
-            <App user={data.user} building={data.building} building_like={data.building_like} />
+            <App
+                user={data.user}
+                building={data.building}
+                building_like={data.building_like}
+                revisionId={data.latestRevisionId}
+            />
         </StaticRouter>
     );