Displaying special page when syncing. 404 instead of redirection

dapps/src/lib.rs

@@ -88,11 +88,22 @@ use ethcore_rpc::Extendable;
 
 static DAPPS_DOMAIN : &'static str = ".parity";
 
+/// Indicates sync status
+pub trait SyncStatus: Send + Sync {
+	/// Returns true if there is a major sync happening.
+	fn is_major_syncing(&self) -> bool;
+}
+
+impl<F> SyncStatus for F where F: Fn() -> bool + Send + Sync {
+	fn is_major_syncing(&self) -> bool { self() }
+}
+
 /// Webapps HTTP+RPC server build.
 pub struct ServerBuilder {
 	dapps_path: String,
 	handler: Arc<IoHandler>,
 	registrar: Arc<ContractClient>,
+	sync_status: Arc<SyncStatus>,
 }
 
 impl Extendable for ServerBuilder {
@@ -108,9 +119,15 @@ impl ServerBuilder {
 			dapps_path: dapps_path,
 			handler: Arc::new(IoHandler::new()),
 			registrar: registrar,
+			sync_status: Arc::new(|| false),
 		}
 	}
 
+	/// Change default sync status.
+	pub fn with_sync_status(&mut self, status: Arc<SyncStatus>) {
+		self.sync_status = status;
+	}
+
 	/// Asynchronously start server with no authentication,
 	/// returns result with `Server` handle on success or an error.
 	pub fn start_unsecured_http(&self, addr: &SocketAddr, hosts: Option<Vec<String>>) -> Result<Server, ServerError> {
@@ -120,7 +137,8 @@ impl ServerBuilder {
 			NoAuth,
 			self.handler.clone(),
 			self.dapps_path.clone(),
-			self.registrar.clone()
+			self.registrar.clone(),
+			self.sync_status.clone(),
 		)
 	}
 
@@ -133,7 +151,8 @@ impl ServerBuilder {
 			HttpBasicAuth::single_user(username, password),
 			self.handler.clone(),
 			self.dapps_path.clone(),
-			self.registrar.clone()
+			self.registrar.clone(),
+			self.sync_status.clone(),
 		)
 	}
 }
@@ -167,10 +186,11 @@ impl Server {
 		handler: Arc<IoHandler>,
 		dapps_path: String,
 		registrar: Arc<ContractClient>,
+		sync_status: Arc<SyncStatus>,
 	) -> Result<Server, ServerError> {
 		let panic_handler = Arc::new(Mutex::new(None));
 		let authorization = Arc::new(authorization);
-		let apps_fetcher = Arc::new(apps::fetcher::AppFetcher::new(apps::urlhint::URLHintContract::new(registrar)));
+		let apps_fetcher = Arc::new(apps::fetcher::AppFetcher::new(apps::urlhint::URLHintContract::new(registrar), sync_status));
 		let endpoints = Arc::new(apps::all_endpoints(dapps_path));
 		let special = Arc::new({
 			let mut special = HashMap::new();