Merge pull request #49 from developmentseed/feature/geocoding

Add geocoder

Author: kamicut

packages/web/package.json

@@ -11,9 +11,11 @@
     "lint": "eslint . --ext .js,.ts,.tsx"
   },
   "dependencies": {
+    "@maplibre/maplibre-gl-geocoder": "^1.5.0",
     "@turf/area": "^6.5.0",
     "@turf/bbox-polygon": "^6.5.0",
     "date-fns": "^3.6.0",
+    "events": "^3.3.0",
     "flatgeobuf": "^3.26.2",
     "lodash.get": "^4.4.2",
     "maplibre-gl": "^3.3.1",
@@ -23,7 +25,9 @@
   "devDependencies": {
     "@babel/runtime": "^7.22.15",
     "@preact/preset-vite": "^2.5.0",
+    "@types/events": "^3.0.3",
     "@types/lodash.get": "^4.4.7",
+    "@types/node": "^20.14.2",
     "@types/turf": "^3.5.32",
     "@typescript-eslint/eslint-plugin": "^6.7.0",
     "@typescript-eslint/parser": "^6.7.0",

packages/web/src/app/map/index.tsx

@@ -1,6 +1,8 @@
 import { useEffect } from "preact/hooks";
 import MapLibreGL, { MapMouseEvent } from "maplibre-gl";
 import { AppActionTypes, AppDispatch, AppState } from "../reducer";
+import MaplibreGeocoder from "@maplibre/maplibre-gl-geocoder";
+import "@maplibre/maplibre-gl-geocoder/dist/maplibre-gl-geocoder.css";
 
 interface MapProps {
   appState: AppState;
@@ -162,6 +164,45 @@ export function Map(props: MapProps) {
         },
       });
 
+      const geocoderApi = {
+        forwardGeocode: async (config: { query: string }) => {
+          const features = [];
+          try {
+            const request = `https://nominatim.openstreetmap.org/search?q=${config.query}&format=geojson&polygon_geojson=1&addressdetails=1`;
+            const response = await fetch(request);
+            const geojson = await response.json();
+            for (const feature of geojson.features) {
+              const center = [
+                feature.bbox[0] + (feature.bbox[2] - feature.bbox[0]) / 2,
+                feature.bbox[1] + (feature.bbox[3] - feature.bbox[1]) / 2,
+              ];
+              const point = {
+                type: "Feature",
+                geometry: {
+                  type: "Point",
+                  coordinates: center,
+                },
+                place_name: feature.properties.display_name,
+                properties: feature.properties,
+                text: feature.properties.display_name,
+                place_type: ["place"],
+                center,
+              };
+              features.push(point);
+            }
+          } catch (e) {
+            // eslint-disable-next-line no-console
+            console.error(`Failed to forwardGeocode with error: ${e}`);
+          }
+
+          return {
+            features,
+          };
+        },
+      };
+
+      map.addControl(new MaplibreGeocoder(geocoderApi, { zoom: 10 }));
+
       function onClick(e: MapMouseEvent) {
         // @ts-expect-error - MapMouseEvent doesn't know about features
         const features = e.features as GeoJSON.Feature[];