Env Vars & Geocode Data Caching

src/geocode.js

@@ -1,4 +1,59 @@
 const https = require('https');
+const fs = require('fs');
+const path = require('path');
+const crypto = require('crypto');
+
+const CACHE_DIR = path.join(__dirname, '..', 'cache');
+
+// Ensure cache directory exists
+if (!fs.existsSync(CACHE_DIR)) {
+  fs.mkdirSync(CACHE_DIR, { recursive: true });
+}
+
+/**
+ * Generate a safe filename from a city query
+ * @param {string} cityQuery - City name
+ * @returns {string} Safe filename
+ */
+function getCacheFileName(cityQuery) {
+  const hash = crypto.createHash('md5').update(cityQuery.toLowerCase().trim()).digest('hex');
+  return `geocode_${hash}.json`;
+}
+
+/**
+ * Get cached geocode data if available
+ * @param {string} cityQuery - City name
+ * @returns {Object|null} Cached data or null
+ */
+function getCachedGeocode(cityQuery) {
+  try {
+    const cacheFile = path.join(CACHE_DIR, getCacheFileName(cityQuery));
+    if (fs.existsSync(cacheFile)) {
+      const data = fs.readFileSync(cacheFile, 'utf8');
+      const cached = JSON.parse(data);
+      console.log(`Using cached geocode for: ${cityQuery}`);
+      return cached;
+    }
+  } catch (error) {
+    console.warn(`Cache read error for ${cityQuery}:`, error.message);
+  }
+  return null;
+}
+
+/**
+ * Save geocode data to cache
+ * @param {string} cityQuery - City name
+ * @param {Object} data - Geocode data to cache
+ */
+function saveCachedGeocode(cityQuery, data) {
+  try {
+    const cacheFile = path.join(CACHE_DIR, getCacheFileName(cityQuery));
+    fs.writeFileSync(cacheFile, JSON.stringify(data, null, 2), 'utf8');
+    console.log(`Cached geocode for: ${cityQuery}`);
+  } catch (error) {
+    console.warn(`Cache write error for ${cityQuery}:`, error.message);
+  }
+}
 
 /**
  * Geocode city to lat/lon using Nominatim (OpenStreetMap)
@@ -6,6 +61,11 @@ const https = require('https');
  * @returns {Promise<{lat: number, lon: number, displayName: string}>}
  */
 async function geocodeCity(cityQuery) {
+  // Check cache first
+  const cached = getCachedGeocode(cityQuery);
+  if (cached) {
+    return cached;
+  }
   return new Promise((resolve, reject) => {
     const encodedQuery = encodeURIComponent(cityQuery);
     const url = `https://nominatim.openstreetmap.org/search?q=${encodedQuery}&format=json&limit=1`;
@@ -27,11 +87,14 @@ async function geocodeCity(cityQuery) {
         try {
           const results = JSON.parse(data);
           if (results && results.length > 0) {
-            resolve({
+            const geocodeResult = {
               lat: parseFloat(results[0].lat),
               lon: parseFloat(results[0].lon),
               displayName: results[0].display_name
-            });
+            };
+            // Save to cache
+            saveCachedGeocode(cityQuery, geocodeResult);
+            resolve(geocodeResult);
           } else {
             reject(new Error('No results found'));
           }