created API For Aplication Absensi

app/helpers/distance.js

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+function getDistance(lat1, lon1, lat2, lon2) {
+    // pastikan semuanya number
+    lat1 = parseFloat(lat1);
+    lon1 = parseFloat(lon1);
+    lat2 = parseFloat(lat2);
+    lon2 = parseFloat(lon2);
+  
+    const R = 6371000; // radius bumi dalam meter
+    const toRad = Math.PI / 180;
+    
+    const dLat = (lat2 - lat1) * toRad;
+    const dLon = (lon2 - lon1) * toRad;
+  
+    const a =
+      Math.sin(dLat / 2) * Math.sin(dLat / 2) +
+      Math.cos(lat1 * toRad) *
+      Math.cos(lat2 * toRad) *
+      Math.sin(dLon / 2) * Math.sin(dLon / 2);
+  
+    const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
+    const distance = R * c;
+  
+    return distance;
+  }
+  
+  module.exports = { getDistance };
+