Return old-ish content even when syncing (#2757)

dapps/src/tests/fetch.rs

@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
-use tests::helpers::{serve_with_registrar, request, assert_security_headers};
+use tests::helpers::{serve_with_registrar, serve_with_registrar_and_sync, request, assert_security_headers};
 
 #[test]
 fn should_resolve_dapp() {
@@ -37,3 +37,31 @@ fn should_resolve_dapp() {
 	assert_security_headers(&response.headers);
 }
 
+#[test]
+fn should_return_503_when_syncing_but_should_make_the_calls() {
+	// given
+	let (server, registrar) = serve_with_registrar_and_sync();
+	{
+		let mut responses = registrar.responses.lock();
+		let res1 = responses.get(0).unwrap().clone();
+		let res2 = responses.get(1).unwrap().clone();
+		// Registrar will be called twice - fill up the responses.
+		responses.push(res1);
+		responses.push(res2);
+	}
+
+	// when
+	let response = request(server,
+		"\
+			GET / HTTP/1.1\r\n\
+			Host: 1472a9e190620cdf6b31f383373e45efcfe869a820c91f9ccd7eb9fb45e4985d.parity\r\n\
+			Connection: close\r\n\
+			\r\n\
+		"
+	);
+
+	// then
+	assert_eq!(response.status, "HTTP/1.1 503 Service Unavailable".to_owned());
+	assert_eq!(registrar.calls.lock().len(), 4);
+	assert_security_headers(&response.headers);
+}

dapps/src/tests/helpers.rs

@@ -69,12 +69,13 @@ fn init_logger() {
 	}
 }
 
-pub fn init_server(hosts: Option<Vec<String>>) -> (Server, Arc<FakeRegistrar>) {
+pub fn init_server(hosts: Option<Vec<String>>, is_syncing: bool) -> (Server, Arc<FakeRegistrar>) {
 	init_logger();
 	let registrar = Arc::new(FakeRegistrar::new());
 	let mut dapps_path = env::temp_dir();
 	dapps_path.push("non-existent-dir-to-prevent-fs-files-from-loading");
 	let mut builder = ServerBuilder::new(dapps_path.to_str().unwrap().into(), registrar.clone());
+	builder.with_sync_status(Arc::new(move || is_syncing));
 	builder.with_signer_port(Some(SIGNER_PORT));
 	(
 		builder.start_unsecured_http(&"127.0.0.1:0".parse().unwrap(), hosts).unwrap(),
@@ -93,15 +94,19 @@ pub fn serve_with_auth(user: &str, pass: &str) -> Server {
 }
 
 pub fn serve_hosts(hosts: Option<Vec<String>>) -> Server {
-	init_server(hosts).0
+	init_server(hosts, false).0
 }
 
 pub fn serve_with_registrar() -> (Server, Arc<FakeRegistrar>) {
-	init_server(None)
+	init_server(None, false)
+}
+
+pub fn serve_with_registrar_and_sync() -> (Server, Arc<FakeRegistrar>) {
+	init_server(None, true)
 }
 
 pub fn serve() -> Server {
-	init_server(None).0
+	init_server(None, false).0
 }
 
 pub fn request(server: Server, request: &str) -> http_client::Response {