Make the default server configurable

mastodon/src/main/java/org/joinmastodon/android/api/MastodonAPIController.java

@@ -24,6 +24,7 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.TimeUnit;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
@@ -86,6 +87,9 @@ public class MastodonAPIController{
 				synchronized(req){
 					req.okhttpCall=call;
 				}
+				if(req.timeout>0){
+					call.timeout().timeout(req.timeout, TimeUnit.MILLISECONDS);
+				}
 
 				if(BuildConfig.DEBUG)
 					Log.d(TAG, "["+(session==null ? "no-auth" : session.getID())+"] Sending request: "+hreq);

mastodon/src/main/java/org/joinmastodon/android/api/MastodonAPIRequest.java

@@ -45,6 +45,7 @@ public abstract class MastodonAPIRequest<T> extends APIRequest<T>{
 	Token token;
 	boolean canceled;
 	Map<String, String> headers;
+	long timeout;
 	private ProgressDialog progressDialog;
 	protected boolean removeUnsupportedItems;
 
@@ -127,6 +128,10 @@ public abstract class MastodonAPIRequest<T> extends APIRequest<T>{
 		headers.put(key, value);
 	}
 
+	protected void setTimeout(long timeout){
+		this.timeout=timeout;
+	}
+
 	protected String getPathPrefix(){
 		return "/api/v1";
 	}

mastodon/src/main/java/org/joinmastodon/android/api/requests/catalog/GetCatalogDefaultInstances.java

@@ -0,0 +1,22 @@
+package org.joinmastodon.android.api.requests.catalog;
+
+import android.net.Uri;
+
+import com.google.gson.reflect.TypeToken;
+
+import org.joinmastodon.android.api.MastodonAPIRequest;
+import org.joinmastodon.android.model.catalog.CatalogDefaultInstance;
+
+import java.util.List;
+
+public class GetCatalogDefaultInstances extends MastodonAPIRequest<List<CatalogDefaultInstance>>{
+	public GetCatalogDefaultInstances(){
+		super(HttpMethod.GET, null, new TypeToken<>(){});
+		setTimeout(500);
+	}
+
+	@Override
+	public Uri getURL(){
+		return Uri.parse("https://api.joinmastodon.org/default-servers");
+	}
+}