cache next and previous lots to speed up paging

handlers/lots-get/next.js

@@ -1,7 +1,7 @@
 import * as configFunctions from '../../helpers/functions.config.js';
-import { getNextLotId } from '../../helpers/lotOccupancyDB/getNextLotId.js';
+import { getNextLotId } from '../../helpers/functions.lots.js';
 export async function handler(request, response) {
-    const lotId = request.params.lotId;
+    const lotId = Number.parseInt(request.params.lotId, 10);
     const nextLotId = await getNextLotId(lotId);
     if (!nextLotId) {
         response.redirect(configFunctions.getProperty('reverseProxy.urlPrefix') +

handlers/lots-get/next.ts

@@ -2,13 +2,13 @@ import type { Request, Response } from 'express'
 
 import * as configFunctions from '../../helpers/functions.config.js'
 
-import { getNextLotId } from '../../helpers/lotOccupancyDB/getNextLotId.js'
+import { getNextLotId } from '../../helpers/functions.lots.js'
 
 export async function handler(
   request: Request,
   response: Response
 ): Promise<void> {
-  const lotId = request.params.lotId
+  const lotId = Number.parseInt(request.params.lotId, 10)
 
   const nextLotId = await getNextLotId(lotId)
 

handlers/lots-get/previous.js

@@ -1,7 +1,7 @@
 import * as configFunctions from '../../helpers/functions.config.js';
-import { getPreviousLotId } from '../../helpers/lotOccupancyDB/getPreviousLotId.js';
+import { getPreviousLotId } from '../../helpers/functions.lots.js';
 export async function handler(request, response) {
-    const lotId = request.params.lotId;
+    const lotId = Number.parseInt(request.params.lotId, 10);
     const previousLotId = await getPreviousLotId(lotId);
     if (!previousLotId) {
         response.redirect(configFunctions.getProperty('reverseProxy.urlPrefix') +

handlers/lots-get/previous.ts

@@ -2,13 +2,13 @@ import type { Request, Response } from 'express'
 
 import * as configFunctions from '../../helpers/functions.config.js'
 
-import { getPreviousLotId } from '../../helpers/lotOccupancyDB/getPreviousLotId.js'
+import { getPreviousLotId } from '../../helpers/functions.lots.js'
 
 export async function handler(
   request: Request,
   response: Response
 ): Promise<void> {
-  const lotId = request.params.lotId
+  const lotId = Number.parseInt(request.params.lotId, 10)
 
   const previousLotId = await getPreviousLotId(lotId)
 

handlers/lots-get/view.js

@@ -1,8 +1,9 @@
 import * as configFunctions from '../../helpers/functions.config.js';
+import { getNextLotId, getPreviousLotId } from '../../helpers/functions.lots.js';
 import { getLot } from '../../helpers/lotOccupancyDB/getLot.js';
 export async function handler(request, response) {
     const lot = await getLot(request.params.lotId);
-    if (!lot) {
+    if (lot === undefined) {
         response.redirect(configFunctions.getProperty('reverseProxy.urlPrefix') +
             '/lots/?error=lotIdNotFound');
         return;
@@ -11,5 +12,9 @@ export async function handler(request, response) {
         headTitle: lot.lotName,
         lot
     });
+    response.on('finish', () => {
+        void getNextLotId(lot.lotId);
+        void getPreviousLotId(lot.lotId);
+    });
 }
 export default handler;

handlers/lots-get/view.ts

@@ -1,6 +1,7 @@
 import type { Request, Response } from 'express'
 
 import * as configFunctions from '../../helpers/functions.config.js'
+import { getNextLotId, getPreviousLotId } from '../../helpers/functions.lots.js'
 
 import { getLot } from '../../helpers/lotOccupancyDB/getLot.js'
 
@@ -10,7 +11,7 @@ export async function handler(
 ): Promise<void> {
   const lot = await getLot(request.params.lotId)
 
-  if (!lot) {
+  if (lot === undefined) {
     response.redirect(
       configFunctions.getProperty('reverseProxy.urlPrefix') +
         '/lots/?error=lotIdNotFound'
@@ -22,6 +23,11 @@ export async function handler(
     headTitle: lot.lotName,
     lot
   })
+
+  response.on('finish', () => {
+    void getNextLotId(lot.lotId)
+    void getPreviousLotId(lot.lotId)
+  })
 }
 
 export default handler

helpers/functions.lots.d.ts

@@ -0,0 +1,2 @@
+export declare function getNextLotId(lotId: number): Promise<number | undefined>;
+export declare function getPreviousLotId(lotId: number): Promise<number | undefined>;

helpers/functions.lots.js

@@ -0,0 +1,31 @@
+import NodeCache from 'node-cache';
+import getPreviousLotIdFromDatabase from './lotOccupancyDB/getPreviousLotId.js';
+import getNextLotIdFromDatabase from './lotOccupancyDB/getNextLotId.js';
+const previousLotIdCache = new NodeCache({
+    stdTTL: 2 * 60
+});
+const nextLotIdCache = new NodeCache({
+    stdTTL: 2 * 60
+});
+export async function getNextLotId(lotId) {
+    let nextLotId = nextLotIdCache.get(lotId);
+    if (nextLotId === undefined) {
+        nextLotId = await getNextLotIdFromDatabase(lotId);
+        if (nextLotId !== undefined) {
+            previousLotIdCache.set(nextLotId, lotId);
+            nextLotIdCache.set(lotId, nextLotId);
+        }
+    }
+    return nextLotId;
+}
+export async function getPreviousLotId(lotId) {
+    let previousLotId = previousLotIdCache.get(lotId);
+    if (previousLotId === undefined) {
+        previousLotId = await getPreviousLotIdFromDatabase(lotId);
+        if (previousLotId !== undefined) {
+            previousLotIdCache.set(lotId, previousLotId);
+            nextLotIdCache.set(previousLotId, lotId);
+        }
+    }
+    return previousLotId;
+}

helpers/functions.lots.ts

@@ -0,0 +1,44 @@
+import NodeCache from 'node-cache'
+
+import getPreviousLotIdFromDatabase from './lotOccupancyDB/getPreviousLotId.js'
+import getNextLotIdFromDatabase from './lotOccupancyDB/getNextLotId.js'
+
+const previousLotIdCache = new NodeCache({
+  stdTTL: 2 * 60 // two minutes
+})
+
+const nextLotIdCache = new NodeCache({
+  stdTTL: 2 * 60 // two minutes
+})
+
+export async function getNextLotId(lotId: number): Promise<number | undefined> {
+  let nextLotId: number | undefined = nextLotIdCache.get(lotId)
+
+  if (nextLotId === undefined) {
+    nextLotId = await getNextLotIdFromDatabase(lotId)
+
+    if (nextLotId !== undefined) {
+      previousLotIdCache.set(nextLotId, lotId)
+      nextLotIdCache.set(lotId, nextLotId)
+    }
+  }
+
+  return nextLotId
+}
+
+export async function getPreviousLotId(
+  lotId: number
+): Promise<number | undefined> {
+  let previousLotId: number | undefined = previousLotIdCache.get(lotId)
+
+  if (previousLotId === undefined) {
+    previousLotId = await getPreviousLotIdFromDatabase(lotId)
+
+    if (previousLotId !== undefined) {
+      previousLotIdCache.set(lotId, previousLotId)
+      nextLotIdCache.set(previousLotId, lotId)
+    }
+  }
+
+  return previousLotId
+}

package-lock.json

@@ -35,6 +35,7 @@
         "http-errors": "^2.0.0",
         "ical-generator": "^3.6.1",
         "leaflet": "^1.9.3",
+        "node-cache": "^5.1.2",
         "papaparse": "^5.3.2",
         "randomcolor": "^0.6.2",
         "session-file-store": "^1.5.0",
@@ -2915,7 +2916,6 @@
       "version": "2.1.2",
       "resolved": "https://registry.npmjs.org/clone/-/clone-2.1.2.tgz",
       "integrity": "sha512-3Pe/CF1Nn94hyhIYpjtiLhdCoEoz0DqQ+988E9gmeEdQZlojxnOb74wctFyuwWQHzqyf9X7C7MG8juUpqBJT8w==",
-      "dev": true,
       "engines": {
         "node": ">=0.8"
       }
@@ -8741,6 +8741,17 @@
       "integrity": "sha512-/ujIVxthRs+7q6hsdjHMaj8hRG9NuWmwrz+JdRwZ14jdFoKSkm+vDsCbF9PLpnSqjaWQJuTmVtcWHNLr+vrOFw==",
       "dev": true
     },
+    "node_modules/node-cache": {
+      "version": "5.1.2",
+      "resolved": "https://registry.npmjs.org/node-cache/-/node-cache-5.1.2.tgz",
+      "integrity": "sha512-t1QzWwnk4sjLWaQAS8CHgOJ+RAfmHpxFWmc36IWTiWHQfs0w5JDMBS1b1ZxQteo0vVVuWJvIUKHDkkeK7vIGCg==",
+      "dependencies": {
+        "clone": "2.x"
+      },
+      "engines": {
+        "node": ">= 8.0.0"
+      }
+    },
     "node_modules/node-domexception": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/node-domexception/-/node-domexception-1.0.0.tgz",
@@ -14873,8 +14884,7 @@
     "clone": {
       "version": "2.1.2",
       "resolved": "https://registry.npmjs.org/clone/-/clone-2.1.2.tgz",
-      "integrity": "sha512-3Pe/CF1Nn94hyhIYpjtiLhdCoEoz0DqQ+988E9gmeEdQZlojxnOb74wctFyuwWQHzqyf9X7C7MG8juUpqBJT8w==",
+      "integrity": "sha512-3Pe/CF1Nn94hyhIYpjtiLhdCoEoz0DqQ+988E9gmeEdQZlojxnOb74wctFyuwWQHzqyf9X7C7MG8juUpqBJT8w=="
-      "dev": true
     },
     "clone-buffer": {
       "version": "1.0.0",
@@ -19340,6 +19350,14 @@
       "integrity": "sha512-/ujIVxthRs+7q6hsdjHMaj8hRG9NuWmwrz+JdRwZ14jdFoKSkm+vDsCbF9PLpnSqjaWQJuTmVtcWHNLr+vrOFw==",
       "dev": true
     },
+    "node-cache": {
+      "version": "5.1.2",
+      "resolved": "https://registry.npmjs.org/node-cache/-/node-cache-5.1.2.tgz",
+      "integrity": "sha512-t1QzWwnk4sjLWaQAS8CHgOJ+RAfmHpxFWmc36IWTiWHQfs0w5JDMBS1b1ZxQteo0vVVuWJvIUKHDkkeK7vIGCg==",
+      "requires": {
+        "clone": "2.x"
+      }
+    },
     "node-domexception": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/node-domexception/-/node-domexception-1.0.0.tgz",

package.json

@@ -59,6 +59,7 @@
     "http-errors": "^2.0.0",
     "ical-generator": "^3.6.1",
     "leaflet": "^1.9.3",
+    "node-cache": "^5.1.2",
     "papaparse": "^5.3.2",
     "randomcolor": "^0.6.2",
     "session-file-store": "^1.5.0",