refactor(client/android): move fetching logic from TypeScript to Go (#…

…2221)

client/src/cordova/plugin/android/java/org/outline/OutlinePlugin.java

@@ -42,6 +42,8 @@
 import org.outline.vpn.Errors;
 import org.outline.vpn.VpnServiceStarter;
 import org.outline.vpn.VpnTunnelService;
+import outline.Outline;
+import outline.FetchResourceResult;
 import platerrors.Platerrors;
 import platerrors.PlatformError;
 
@@ -57,6 +59,7 @@ public enum Action {
     STOP("stop"),
     ON_STATUS_CHANGE("onStatusChange"),
     IS_RUNNING("isRunning"),
+    FETCH_RESOURCE("fetchResource"),
     INIT_ERROR_REPORTING("initializeErrorReporting"),
     REPORT_EVENTS("reportEvents"),
     QUIT("quitApplication");
@@ -202,6 +205,17 @@ private void executeAsync(
           final String tunnelId = args.getString(0);
           boolean isActive = isTunnelActive(tunnelId);
           callback.sendPluginResult(new PluginResult(PluginResult.Status.OK, isActive));
+        } else if (Action.FETCH_RESOURCE.is(action)) {
+          final String url = args.getString(0);
+          LOG.fine(String.format(Locale.ROOT, "Fetching resource at %s ...", url));
+          final FetchResourceResult result = Outline.fetchResource(url);
+          if (result.getError() != null) {
+            LOG.warning(String.format(Locale.ROOT, "Fetch resource failed: %s", result.getError()));
+            sendActionResult(callback, result.getError());
+          } else {
+            LOG.info(String.format(Locale.ROOT, "Fetch resource result: %s", result.getContent()));
+            callback.success(result.getContent());
+          }
 
           // Static actions
         } else if (Action.INIT_ERROR_REPORTING.is(action)) {

client/src/www/app/main.cordova.ts

@@ -32,6 +32,7 @@ import {CordovaVpnApi} from './outline_server_repository/vpn.cordova';
 import {OutlinePlatform} from './platform';
 import {OUTLINE_PLUGIN_NAME, pluginExec} from './plugin.cordova';
 import {BrowserResourceFetcher, ResourceFetcher} from './resource_fetcher';
+import {CordovaResourceFetcher} from './resource_fetcher.cordova';
 import {AbstractUpdater} from './updater';
 import * as interceptors from './url_interceptor';
 import {NoOpVpnInstaller, VpnInstaller} from './vpn_installer';
@@ -117,6 +118,9 @@ class CordovaPlatform implements OutlinePlatform {
   }
 
   getResourceFetcher(): ResourceFetcher {
+    if (cordova.platformId === 'android') {
+      return new CordovaResourceFetcher();
+    }
     // TODO: move to Go fetch implementation later
     return new BrowserResourceFetcher();
   }

client/src/www/app/resource_fetcher.cordova.ts

@@ -0,0 +1,25 @@
+// Copyright 2024 The Outline Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import {pluginExecWithErrorCode} from './plugin.cordova';
+import {ResourceFetcher} from './resource_fetcher';
+
+/**
+ * Fetches resources using Cordova plugin.
+ */
+export class CordovaResourceFetcher implements ResourceFetcher {
+  fetch(url: string): Promise<string> {
+    return pluginExecWithErrorCode<string>('fetchResource', url);
+  }
+}