update: get_relation, return json coords

app/lib/pages/widgets/cloropleth_map.dart

+import 'dart:convert';
+
 import 'package:flutter/material.dart';
-import '../marker_handler/marker_data.dart';
+import 'package:http/http.dart' as http;
+import 'package:syncfusion_flutter_maps/maps.dart';
 
-// From https://www.syncfusion.com/blogs/post/create-choropleth-map-using-in-flutter.aspx
 class _ChoroplethMapState extends State {
-  List<Measurement> iceThickness;
-  MapShapeSource _mapShapeSource;
+  late MapShapeSource mapShapeSource;
 
   @override
   void initState() {
     super.initState();
-
-    _mapShapeSource = MapShapeSource.asset(
-      'assets/world_map.json',
-      shapeDataField: 'name',
-      dataCount: _mapShapeSource.length,
-      primaryValueMapper: (int index) =>
-      _mapShapeSource[index].countryName,
-    );
+    getRelation().then((geojsonData) {
+      setState(() {
+        mapShapeSource = MapShapeSource.geoJson(
+          geojsonData,
+          shapeDataField: 'features',
+          primaryValueMapper: (Map<String, dynamic> shapeData) {
+            return shapeData['Mjøsa'];
+          },
+        );
+      });
+    }).catchError((error) {
+      throw Exception('Failed to retrieve geojson data');
+    });
   }
 
   @override
@@ -24,10 +30,23 @@ class _ChoroplethMapState extends State {
     return SfMaps(
       layers: [
         MapShapeLayer(
-            source: _mapShapeSource,
-            strokeColor: Colors.white30
+        source: mapShapeSource,
+        strokeColor: Colors.white30,
+        legend: const MapLegend.bar(MapElement.shape,
+            position: MapLegendPosition.bottom,
+            segmentSize: Size(55.0, 9.0)
+        )
         ),
       ],
     );
   }
-}
\ No newline at end of file
+
+  Future<String> getRelation() async {
+    final response = await http.get(Uri.parse('get_relation'));
+    if (response.statusCode == 200) {
+      return response.body;
+    } else {
+      throw Exception('Failed to retrieve geojson data');
+    }
+  }
+}

app/pubspec.lock

@@ -119,10 +119,10 @@ packages:
     dependency: "direct main"
     description:
       name: http
-      sha256: "5895291c13fa8a3bd82e76d5627f69e0d85ca6a30dcac95c4ea19a5d555879c2"
+      sha256: "6aa2946395183537c8b880962d935877325d6a09a2867c3970c05c0fed6ac482"
       url: "https://pub.dev"
     source: hosted
-    version: "0.13.6"
+    version: "0.13.5"
   http_parser:
     dependency: transitive
     description:
@@ -360,6 +360,22 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.2.0"
+  syncfusion_flutter_core:
+    dependency: transitive
+    description:
+      name: syncfusion_flutter_core
+      sha256: "3979f0b1c5a97422cadae52d476c21fa3e0fb671ef51de6cae1d646d8b99fe1f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "20.4.54"
+  syncfusion_flutter_maps:
+    dependency: "direct main"
+    description:
+      name: syncfusion_flutter_maps
+      sha256: "1c95924e2dee5bbad922c2d2f1d5fb1b13ce4548c34a6d30fe6bf8821dfcfcd6"
+      url: "https://pub.dev"
+    source: hosted
+    version: "20.4.54"
   term_glyph:
     dependency: transitive
     description:

app/pubspec.yaml

@@ -15,6 +15,7 @@ dependencies:
   provider: ^5.0.0
   fl_chart: ^0.20.0-nullsafety1
   google_fonts: any
+  syncfusion_flutter_maps: ^20.4.41
 
 dev_dependencies:
   flutter_test:

server/main.py

@@ -2,6 +2,7 @@ from flask import Flask
 from http.server import HTTPServer, BaseHTTPRequestHandler
 from consts import SSL_CERT_PATH, SSL_KEY_PATH, HOST, PORT
 from map.get_markers import get_all_markers
+from map.get_relation import get_relation
 from APIs.get_weather import get_weather
 import ssl
 import keyboard
@@ -41,6 +42,8 @@ class IceHTTP(BaseHTTPRequestHandler):
         elif self.path == '/get_valid_markers':  # NB: should be POST?
             get_all_markers(self, self.cursor, True, 'Mjosa')  # Get only valid markers
             # NB: temporary hardcoded waterBodyName
+        elif self.path == '/get_relation':
+            get_relation(self, 'Mjosa') # NB temp hardcoded value
 
     def do_POST(self):
         if self.path == '/get_weather_data':

server/map/get_relation.py

+import string
+import json
+
+
+# get_relation returns the geojson data for a selected body of water
+def get_relation(self, body_of_water: string):
+    # Read geojson file
+    with open("server/map/" + body_of_water.lower() + ".geojson") as f:
+        data = json.load(f)
+
+    # Extracting coordinates from the GeoJSON features
+    coordinates = []
+    for feature in data['features']:
+        if feature['geometry']['type'] == 'Polygon':
+            coordinates.extend(feature['geometry']['coordinates'][0])
+        elif feature['geometry']['type'] == 'MultiPolygon':
+            for polygon_coords in feature['geometry']['coordinates']:
+                coordinates.extend(polygon_coords[0])
+
+    # Convert response data to JSON string
+    response_json = json.dumps(coordinates)
+
+    # Set headers
+    self.send_response(200)
+    self.send_header("Content-type", "application/json")
+    self.end_headers()
+
+    # Write coordinates to response object
+    self.wfile.write(response_json.encode('utf-8'))