data sample prepared

src/cities.json

@@ -0,0 +1,27 @@
+[
+  {
+    "name": "warsaw",
+    "latitude": 52.24,
+    "longitude": 21.02
+  },
+  {
+    "name": "berlin",
+    "latitude": 52.52,
+    "longitude": 13.40
+  },
+  {
+    "name": "chicago",
+    "latitude": 41.88,
+    "longitude": -87.62
+  },
+  {
+    "name": "vancouver",
+    "latitude": 49.25,
+    "longitude": -123.12
+  },
+  {
+    "name": "tokyo",
+    "latitude": 35.65,
+    "longitude": 139.84
+  }
+]