caching data from user's pluviometer

src/app/hooks/usePluviometricStation.js

@@ -1,6 +1,7 @@
 import { useState } from "react";
 import getFieldsAnswers from "../api/RequestFieldsAnswers/getFieldsAnswers";
 import webSocketClient from "../api/Websockets/webSocketClient";
+import cache from "../utility/cache";
 
 async function getPluvStation_data(id) {
   const result = await getFieldsAnswers.fieldsAnswers(null, id);
@@ -58,15 +59,18 @@ async function getPluviometerStation(userId, setPluviometerStation) {
         pluvStation_data.data.responseData.array_to_json[0]
       );
       setPluviometerStation(pluvObject);
+      cache.store(socketObject, JSON.stringify(pluvObject))
     } else {
       setPluviometerStation(false);
+      cache.store(socketObject, false)
     }
     socketObject.close();
   };
 
-  socketObject.onerror = (e) => {
+  socketObject.onerror = async (e) => {
+    const dataCache = await cache.get(url);
     console.log(e.message);
-    setPluviometerStation(undefined);
+    setPluviometerStation(dataCache);
   };
 }
 

src/app/utility/cache.js

@@ -0,0 +1,43 @@
+import AsyncStorage from "@react-native-async-storage/async-storage";
+import moment from "moment";
+
+const prefix = "cache";
+const expiryInMinutes = 5;
+
+const store = async (key, value) => {
+  try {
+    const item = {
+      value,
+      timestamp: Date.now(),
+    };
+    await AsyncStorage.setItem(prefix + key, JSON.stringify(value));
+  } catch (error) {
+    console.log(error);
+  }
+};
+
+const isExpired =  (intem) => {
+  const now = moment(Date.now());
+  const storedTime = moment(item.timestamp);
+  return now.diff(storedTime, "minutes") > expiryInMinutes;
+};
+
+const get = async(key) => {
+  try {
+    const value = await AsyncStorage.get(prefix + key);
+
+    if (!item) return null;
+
+    if (isExpired(isExperired)) {
+      await AsyncStorage.removeItem(prefix + key);
+      return null;
+    }
+  } catch (error) {
+    console.log(error);
+  }
+};
+
+export default {
+  store,
+  get,
+};