fallback to google api in case of error

index.js

@@ -1,22 +1,3 @@
-import { NativeModules } from 'react-native';
+import Geocoder from './js/geocoder.js';
 
-const { RNGeocoder } = NativeModules;
-
-export default {
-
-  geocodePosition(position) {
-    if (!position || !position.lat || !position.lng) {
-      return Promise.reject(new Error("invalid position: {lat, lng} required"));
-    }
-
-    return RNGeocoder.geocodePosition(position);
-  },
-
-  geocodeAddress(address) {
-    if (!address) {
-      return Promise.reject(new Error("address is null"));
-    }
-
-    return RNGeocoder.geocodeAddress(address);
-  },
-}
+export default Geocoder;

js/geocoder.js

@@ -0,0 +1,34 @@
+import { NativeModules } from 'react-native';
+import GoogleApi from './googleApi.js';
+
+const { RNGeocoder } = NativeModules;
+
+export default {
+  apiKey: null,
+
+  fallbackToGoogle(key) {
+    this.apiKey = key;
+  },
+
+  geocodePosition(position) {
+    if (!position || !position.lat || !position.lng) {
+      return Promise.reject(new Error("invalid position: {lat, lng} required"));
+    }
+
+    return RNGeocoder.geocodePosition(position).catch(err => {
+      if (!this.apiKey) { throw err; }
+      return GoogleApi.geocodePosition(this.apiKey, position);
+    });
+  },
+
+  geocodeAddress(address) {
+    if (!address) {
+      return Promise.reject(new Error("address is null"));
+    }
+
+    return RNGeocoder.geocodeAddress(address).catch(err => {
+      if (!this.apiKey) { throw err; }
+      return GoogleApi.geocodeAddress(this.apiKey, address);
+    });
+  },
+}

js/googleApi.js

@@ -0,0 +1,87 @@
+const googleUrl = 'https://maps.google.com/maps/api/geocode/json';
+
+function format(raw) {
+  const address = {
+    position: {},
+    formattedAddress: raw.formatted_address || '',
+    feature: null,
+    streetNumber: null,
+    streetName: null,
+    postalCode: null,
+    locality: null,
+    country: null,
+    countryCode: null,
+    adminArea: null,
+    subAdminArea: null,
+    subLocality: null,
+  };
+
+  if (raw.geometry && raw.geometry.location) {
+    address.position = {
+      lat: raw.geometry.location.lat,
+      lng: raw.geometry.location.lng,
+    }
+  }
+
+  for (let component of raw.address_components) {
+    if (component.types.includes('route')) {
+      address.streetName = component.long_name;
+    }
+    else if (component.types.includes('street_number')) {
+      address.streetNumber = component.long_name;
+    }
+    else if (component.types.includes('country')) {
+      address.country = component.long_name;
+      address.countryCode = component.short_name;
+    }
+    else if (component.types.includes('locality')) {
+      address.locality = component.long_name;
+    }
+    else if (component.types.includes('postal_code')) {
+      address.postalCode = component.long_name;
+    }
+    else if (component.types.includes('administrative_area_level_1')) {
+      address.adminArea = component.long_name;
+    }
+    else if (component.types.includes('administrative_area_level_2')) {
+      address.subAdminArea = component.long_name;
+    }
+    else if (component.types.includes('sublocality') || component.types.includes('sublocality_level_1')) {
+      address.subLocality = component.long_name;
+    }
+    else if (component.types.includes('point_of_interest') || component.types.includes('colloquial_area')) {
+      address.feature = component.long_name;
+    }
+  }
+
+  return address;
+}
+
+export default {
+  geocodePosition(apiKey, position) {
+    if (!apiKey || !position || !position.lat || !position.lng) {
+      return Promise.reject(new Error("invalid apiKey / position"));
+    }
+
+    return this.googleRequest(`${googleUrl}?key=${apiKey}&latlng=${position.lat},${position.lng}`);
+  },
+
+  geocodeAddress(apiKey, address) {
+    if (!apiKey || !address) {
+      return Promise.reject(new Error("invalid apiKey / address"));
+    }
+
+    return this.googleRequest(`${googleUrl}?key=${apiKey}&address=${encodeURI(address)}`);
+  },
+
+  async googleRequest(url) {
+    const res = await fetch(url);
+    const json = await res.json();
+
+    if (!json.results || json.status !== 'OK') {
+      return Promise.reject(new Error(`geocoding error ${json.status}, ${json.error_message}`));
+    }
+
+    return json.results.map(format);
+  }
+}