Merge pull request #2055 from ethcore/dapp-norefresh

Get rid of 'Dapp is being downloaded' page

dapps/src/apps/cache.rs

@@ -18,13 +18,13 @@
 
 use std::fs;
 use std::sync::{Arc};
-use std::sync::atomic::{AtomicBool, Ordering};
 
 use linked_hash_map::LinkedHashMap;
 use page::LocalPageEndpoint;
+use handlers::FetchControl;
 
 pub enum ContentStatus {
-	Fetching(Arc<AtomicBool>),
+	Fetching(Arc<FetchControl>),
 	Ready(LocalPageEndpoint),
 }
 
@@ -57,10 +57,10 @@ impl ContentCache {
 		while len > expected_size {
 			let entry = self.cache.pop_front().unwrap();
 			match entry.1 {
-				ContentStatus::Fetching(ref abort) => {
+				ContentStatus::Fetching(ref fetch) => {
 					trace!(target: "dapps", "Aborting {} because of limit.", entry.0);
 					// Mark as aborted
-					abort.store(true, Ordering::SeqCst);
+					fetch.abort()
 				},
 				ContentStatus::Ready(ref endpoint) => {
 					trace!(target: "dapps", "Removing {} because of limit.", entry.0);

dapps/src/apps/fetcher.rs

@@ -23,7 +23,6 @@ use std::{fs, env, fmt};
 use std::io::{self, Read, Write};
 use std::path::PathBuf;
 use std::sync::Arc;
-use std::sync::atomic::{AtomicBool};
 use rustc_serialize::hex::FromHex;
 
 use hyper;
@@ -76,10 +75,12 @@ impl<R: URLHint> ContentFetcher<R> {
 	}
 
 	pub fn contains(&self, content_id: &str) -> bool {
-		let mut cache = self.cache.lock();
+		{
-		// Check if we already have the app
+			let mut cache = self.cache.lock();
-		if cache.get(content_id).is_some() {
+			// Check if we already have the app
-			return true;
+			if cache.get(content_id).is_some() {
+				return true;
+			}
 		}
 		// fallback to resolver
 		if let Ok(content_id) = content_id.from_hex() {
@@ -115,49 +116,60 @@ impl<R: URLHint> ContentFetcher<R> {
 					(None, endpoint.to_async_handler(path, control))
 				},
 				// App is already being fetched
-				Some(&mut ContentStatus::Fetching(_)) => {
+				Some(&mut ContentStatus::Fetching(ref fetch_control)) => {
-					(None, Box::new(ContentHandler::error_with_refresh(
+					trace!(target: "dapps", "Content fetching in progress. Waiting...");
-						StatusCode::ServiceUnavailable,
+					(None, fetch_control.to_handler(control))
-						"Download In Progress",
-						"This dapp is already being downloaded. Please wait...",
-						None,
-					)) as Box<Handler>)
 				},
 				// We need to start fetching app
 				None => {
+					trace!(target: "dapps", "Content unavailable. Fetching...");
 					let content_hex = content_id.from_hex().expect("to_handler is called only when `contains` returns true.");
 					let content = self.resolver.resolve(content_hex);
-					let abort = Arc::new(AtomicBool::new(false));
+
+					let cache = self.cache.clone();
+					let on_done = move |id: String, result: Option<LocalPageEndpoint>| {
+						let mut cache = cache.lock();
+						match result {
+							Some(endpoint) => {
+								cache.insert(id, ContentStatus::Ready(endpoint));
+							},
+							// In case of error
+							None => {
+								cache.remove(&id);
+							},
+						}
+					};
 
 					match content {
-						Some(URLHintResult::Dapp(dapp)) => (
+						Some(URLHintResult::Dapp(dapp)) => {
-							Some(ContentStatus::Fetching(abort.clone())),
+							let (handler, fetch_control) = ContentFetcherHandler::new(
-							Box::new(ContentFetcherHandler::new(
 								dapp.url(),
-								abort,
 								control,
 								path.using_dapps_domains,
 								DappInstaller {
 									id: content_id.clone(),
 									dapps_path: self.dapps_path.clone(),
-									cache: self.cache.clone(),
+									on_done: Box::new(on_done),
-								})) as Box<Handler>
+								}
-						),
+							);
-						Some(URLHintResult::Content(content)) => (
+
-							Some(ContentStatus::Fetching(abort.clone())),
+							(Some(ContentStatus::Fetching(fetch_control)), Box::new(handler) as Box<Handler>)
-							Box::new(ContentFetcherHandler::new(
+						},
+						Some(URLHintResult::Content(content)) => {
+							let (handler, fetch_control) = ContentFetcherHandler::new(
 								content.url,
-								abort,
 								control,
 								path.using_dapps_domains,
 								ContentInstaller {
 									id: content_id.clone(),
 									mime: content.mime,
 									content_path: self.dapps_path.clone(),
-									cache: self.cache.clone(),
+									on_done: Box::new(on_done),
 								}
-							)) as Box<Handler>,
+							);
-						),
+
+							(Some(ContentStatus::Fetching(fetch_control)), Box::new(handler) as Box<Handler>)
+						},
 						None => {
 							// This may happen when sync status changes in between
 							// `contains` and `to_handler`
@@ -225,14 +237,13 @@ struct ContentInstaller {
 	id: String,
 	mime: String,
 	content_path: PathBuf,
-	cache: Arc<Mutex<ContentCache>>,
+	on_done: Box<Fn(String, Option<LocalPageEndpoint>) + Send>,
 }
 
 impl ContentValidator for ContentInstaller {
 	type Error = ValidationError;
-	type Result = PathBuf;
 
-	fn validate_and_install(&self, path: PathBuf) -> Result<(String, PathBuf), ValidationError> {
+	fn validate_and_install(&self, path: PathBuf) -> Result<(String, LocalPageEndpoint), ValidationError> {
 		// Create dir
 		try!(fs::create_dir_all(&self.content_path));
 
@@ -247,21 +258,11 @@ impl ContentValidator for ContentInstaller {
 
 		try!(fs::copy(&path, &content_path));
 
-		Ok((self.id.clone(), content_path))
+		Ok((self.id.clone(), LocalPageEndpoint::single_file(content_path, self.mime.clone())))
 	}
 
-	fn done(&self, result: Option<&PathBuf>) {
+	fn done(&self, endpoint: Option<LocalPageEndpoint>) {
-		let mut cache = self.cache.lock();
+		(self.on_done)(self.id.clone(), endpoint)
-		match result {
-			Some(result) => {
-				let page = LocalPageEndpoint::single_file(result.clone(), self.mime.clone());
-				cache.insert(self.id.clone(), ContentStatus::Ready(page));
-			},
-			// In case of error
-			None => {
-				cache.remove(&self.id);
-			},
-		}
 	}
 }
 
@@ -269,7 +270,7 @@ impl ContentValidator for ContentInstaller {
 struct DappInstaller {
 	id: String,
 	dapps_path: PathBuf,
-	cache: Arc<Mutex<ContentCache>>,
+	on_done: Box<Fn(String, Option<LocalPageEndpoint>) + Send>,
 }
 
 impl DappInstaller {
@@ -306,9 +307,8 @@ impl DappInstaller {
 
 impl ContentValidator for DappInstaller {
 	type Error = ValidationError;
-	type Result = Manifest;
 
-	fn validate_and_install(&self, app_path: PathBuf) -> Result<(String, Manifest), ValidationError> {
+	fn validate_and_install(&self, app_path: PathBuf) -> Result<(String, LocalPageEndpoint), ValidationError> {
 		trace!(target: "dapps", "Opening dapp bundle at {:?}", app_path);
 		let mut file_reader = io::BufReader::new(try!(fs::File::open(app_path)));
 		let hash = try!(sha3(&mut file_reader));
@@ -362,23 +362,15 @@ impl ContentValidator for DappInstaller {
 		let mut manifest_file = try!(fs::File::create(manifest_path));
 		try!(manifest_file.write_all(manifest_str.as_bytes()));
 
+		// Create endpoint
+		let app = LocalPageEndpoint::new(target, manifest.clone().into());
+
 		// Return modified app manifest
-		Ok((manifest.id.clone(), manifest))
+		Ok((manifest.id.clone(), app))
 	}
 
-	fn done(&self, manifest: Option<&Manifest>) {
+	fn done(&self, endpoint: Option<LocalPageEndpoint>) {
-		let mut cache = self.cache.lock();
+		(self.on_done)(self.id.clone(), endpoint)
-		match manifest {
-			Some(manifest) => {
-				let path = self.dapp_target_path(manifest);
-				let app = LocalPageEndpoint::new(path, manifest.clone().into());
-				cache.insert(self.id.clone(), ContentStatus::Ready(app));
-			},
-			// In case of error
-			None => {
-				cache.remove(&self.id);
-			},
-		}
 	}
 }
 

dapps/src/error_tpl.html

@@ -3,7 +3,6 @@
 	<head>
 		<meta charset="utf-8">
 		<meta name="viewport" content="width=device-width">
-		{meta}
 		<title>{title}</title>
 		<link rel="stylesheet" href="/parity-utils/styles.css">
 	</head>

dapps/src/handlers/content.rs

@@ -23,6 +23,7 @@ use hyper::status::StatusCode;
 
 use util::version;
 
+#[derive(Clone)]
 pub struct ContentHandler {
 	code: StatusCode,
 	content: String,
@@ -57,18 +58,6 @@ impl ContentHandler {
 		Self::html(code, format!(
 			include_str!("../error_tpl.html"),
 			title=title,
-			meta="",
-			message=message,
-			details=details.unwrap_or_else(|| ""),
-			version=version(),
-		))
-	}
-
-	pub fn error_with_refresh(code: StatusCode, title: &str, message: &str, details: Option<&str>) -> Self {
-		Self::html(code, format!(
-			include_str!("../error_tpl.html"),
-			title=title,
-			meta="<meta http-equiv=\"refresh\" content=\"1\">",
 			message=message,
 			details=details.unwrap_or_else(|| ""),
 			version=version(),

dapps/src/handlers/fetch.rs

@@ -19,41 +19,122 @@
 use std::{fs, fmt};
 use std::path::PathBuf;
 use std::sync::{mpsc, Arc};
-use std::sync::atomic::AtomicBool;
+use std::sync::atomic::{AtomicBool, Ordering};
 use std::time::{Instant, Duration};
+use util::Mutex;
 
-use hyper::{header, server, Decoder, Encoder, Next, Method, Control};
+use hyper::{server, Decoder, Encoder, Next, Method, Control};
 use hyper::net::HttpStream;
 use hyper::status::StatusCode;
 
-use handlers::ContentHandler;
+use handlers::{ContentHandler, Redirection};
 use handlers::client::{Client, FetchResult};
 use apps::redirection_address;
+use page::LocalPageEndpoint;
 
 const FETCH_TIMEOUT: u64 = 30;
 
-enum FetchState<T: fmt::Debug> {
+enum FetchState {
 	NotStarted(String),
 	Error(ContentHandler),
-	InProgress {
+	InProgress(mpsc::Receiver<FetchResult>),
-		deadline: Instant,
+	Done(String, LocalPageEndpoint, Redirection),
-		receiver: mpsc::Receiver<FetchResult>,
-	},
-	Done((String, T)),
 }
 
 pub trait ContentValidator {
 	type Error: fmt::Debug + fmt::Display;
-	type Result: fmt::Debug;
 
-	fn validate_and_install(&self, app: PathBuf) -> Result<(String, Self::Result), Self::Error>;
+	fn validate_and_install(&self, app: PathBuf) -> Result<(String, LocalPageEndpoint), Self::Error>;
-	fn done(&self, Option<&Self::Result>);
+	fn done(&self, Option<LocalPageEndpoint>);
+}
+
+pub struct FetchControl {
+	abort: Arc<AtomicBool>,
+	listeners: Mutex<Vec<(Control, mpsc::Sender<FetchState>)>>,
+	deadline: Instant,
+}
+
+impl Default for FetchControl {
+	fn default() -> Self {
+		FetchControl {
+			abort: Arc::new(AtomicBool::new(false)),
+			listeners: Mutex::new(Vec::new()),
+			deadline: Instant::now() + Duration::from_secs(FETCH_TIMEOUT),
+		}
+	}
+}
+
+impl FetchControl {
+	fn notify<F: Fn() -> FetchState>(&self, status: F) {
+		let mut listeners = self.listeners.lock();
+		for (control, sender) in listeners.drain(..) {
+			if let Err(e) = sender.send(status()) {
+				trace!(target: "dapps", "Waiting listener notification failed: {:?}", e);
+			} else {
+				let _ = control.ready(Next::read());
+			}
+		}
+	}
+
+	fn set_status(&self, status: &FetchState) {
+		match *status {
+			FetchState::Error(ref handler) => self.notify(|| FetchState::Error(handler.clone())),
+			FetchState::Done(ref id, ref endpoint, ref handler) => self.notify(|| FetchState::Done(id.clone(), endpoint.clone(), handler.clone())),
+			FetchState::NotStarted(_) | FetchState::InProgress(_) => {},
+		}
+	}
+
+	pub fn abort(&self) {
+		self.abort.store(true, Ordering::SeqCst);
+	}
+
+	pub fn to_handler(&self, control: Control) -> Box<server::Handler<HttpStream> + Send> {
+		let (tx, rx) = mpsc::channel();
+		self.listeners.lock().push((control, tx));
+
+		Box::new(WaitingHandler {
+			receiver: rx,
+			state: None,
+		})
+	}
+}
+
+pub struct WaitingHandler {
+	receiver: mpsc::Receiver<FetchState>,
+	state: Option<FetchState>,
+}
+
+impl server::Handler<HttpStream> for WaitingHandler {
+	fn on_request(&mut self, _request: server::Request<HttpStream>) -> Next {
+		Next::wait()
+	}
+
+	fn on_request_readable(&mut self, _decoder: &mut Decoder<HttpStream>) -> Next {
+		self.state = self.receiver.try_recv().ok();
+		Next::write()
+	}
+
+	fn on_response(&mut self, res: &mut server::Response) -> Next {
+		match self.state {
+			Some(FetchState::Done(_, _, ref mut handler)) => handler.on_response(res),
+			Some(FetchState::Error(ref mut handler)) => handler.on_response(res),
+			_ => Next::end(),
+		}
+	}
+
+	fn on_response_writable(&mut self, encoder: &mut Encoder<HttpStream>) -> Next {
+		match self.state {
+			Some(FetchState::Done(_, _, ref mut handler)) => handler.on_response_writable(encoder),
+			Some(FetchState::Error(ref mut handler)) => handler.on_response_writable(encoder),
+			_ => Next::end(),
+		}
+	}
 }
 
 pub struct ContentFetcherHandler<H: ContentValidator> {
-	abort: Arc<AtomicBool>,
+	fetch_control: Arc<FetchControl>,
 	control: Option<Control>,
-	status: FetchState<H::Result>,
+	status: FetchState,
 	client: Option<Client>,
 	using_dapps_domains: bool,
 	installer: H,
@@ -62,7 +143,7 @@ pub struct ContentFetcherHandler<H: ContentValidator> {
 impl<H: ContentValidator> Drop for ContentFetcherHandler<H> {
 	fn drop(&mut self) {
 		let result = match self.status {
-			FetchState::Done((_, ref result)) => Some(result),
+			FetchState::Done(_, ref result, _) => Some(result.clone()),
 			_ => None,
 		};
 		self.installer.done(result);
@@ -73,20 +154,22 @@ impl<H: ContentValidator> ContentFetcherHandler<H> {
 
 	pub fn new(
 		url: String,
-		abort: Arc<AtomicBool>,
 		control: Control,
 		using_dapps_domains: bool,
-		handler: H) -> Self {
+		handler: H) -> (Self, Arc<FetchControl>) {
 
+		let fetch_control = Arc::new(FetchControl::default());
 		let client = Client::new();
-		ContentFetcherHandler {
+		let handler = ContentFetcherHandler {
-			abort: abort,
+			fetch_control: fetch_control.clone(),
 			control: Some(control),
 			client: Some(client),
 			status: FetchState::NotStarted(url),
 			using_dapps_domains: using_dapps_domains,
 			installer: handler,
-		}
+		};
+
+		(handler, fetch_control)
 	}
 
 	fn close_client(client: &mut Option<Client>) {
@@ -95,7 +178,6 @@ impl<H: ContentValidator> ContentFetcherHandler<H> {
 			.close();
 	}
 
-
 	fn fetch_content(client: &mut Client, url: &str, abort: Arc<AtomicBool>, control: Control) -> Result<mpsc::Receiver<FetchResult>, String> {
 		client.request(url, abort, Box::new(move || {
 			trace!(target: "dapps", "Fetching finished.");
@@ -114,12 +196,9 @@ impl<H: ContentValidator> server::Handler<HttpStream> for ContentFetcherHandler<
 					trace!(target: "dapps", "Fetching content from: {:?}", url);
 					let control = self.control.take().expect("on_request is called only once, thus control is always Some");
 					let client = self.client.as_mut().expect("on_request is called before client is closed.");
-					let fetch = Self::fetch_content(client, url, self.abort.clone(), control);
+					let fetch = Self::fetch_content(client, url, self.fetch_control.abort.clone(), control);
 					match fetch {
-						Ok(receiver) => FetchState::InProgress {
+						Ok(receiver) => FetchState::InProgress(receiver),
-							deadline: Instant::now() + Duration::from_secs(FETCH_TIMEOUT),
-							receiver: receiver,
-						},
 						Err(e) => FetchState::Error(ContentHandler::error(
 							StatusCode::BadGateway,
 							"Unable To Start Dapp Download",
@@ -139,6 +218,7 @@ impl<H: ContentValidator> server::Handler<HttpStream> for ContentFetcherHandler<
 		} else { None };
 
 		if let Some(status) = status {
+			self.fetch_control.set_status(&status);
 			self.status = status;
 		}
 
@@ -148,7 +228,7 @@ impl<H: ContentValidator> server::Handler<HttpStream> for ContentFetcherHandler<
 	fn on_request_readable(&mut self, decoder: &mut Decoder<HttpStream>) -> Next {
 		let (status, next) = match self.status {
 			// Request may time out
-			FetchState::InProgress { ref deadline, .. } if *deadline < Instant::now() => {
+			FetchState::InProgress(_) if self.fetch_control.deadline < Instant::now() => {
 				trace!(target: "dapps", "Fetching dapp failed because of timeout.");
 				let timeout = ContentHandler::error(
 					StatusCode::GatewayTimeout,
@@ -159,7 +239,7 @@ impl<H: ContentValidator> server::Handler<HttpStream> for ContentFetcherHandler<
 				Self::close_client(&mut self.client);
 				(Some(FetchState::Error(timeout)), Next::write())
 			},
-			FetchState::InProgress { ref receiver, .. } => {
+			FetchState::InProgress(ref receiver) => {
 				// Check if there is an answer
 				let rec = receiver.try_recv();
 				match rec {
@@ -178,7 +258,10 @@ impl<H: ContentValidator> server::Handler<HttpStream> for ContentFetcherHandler<
 									Some(&format!("{:?}", e))
 								))
 							},
-							Ok(result) => FetchState::Done(result)
+							Ok((id, result)) => {
+								let address = redirection_address(self.using_dapps_domains, &id);
+								FetchState::Done(id, result, Redirection::new(&address))
+							},
 						};
 						// Remove temporary zip file
 						let _ = fs::remove_file(path);
@@ -203,6 +286,7 @@ impl<H: ContentValidator> server::Handler<HttpStream> for ContentFetcherHandler<
 		};
 
 		if let Some(status) = status {
+			self.fetch_control.set_status(&status);
 			self.status = status;
 		}
 
@@ -211,12 +295,7 @@ impl<H: ContentValidator> server::Handler<HttpStream> for ContentFetcherHandler<
 
 	fn on_response(&mut self, res: &mut server::Response) -> Next {
 		match self.status {
-			FetchState::Done((ref id, _)) => {
+			FetchState::Done(_, _, ref mut handler) => handler.on_response(res),
-				trace!(target: "dapps", "Fetching content finished. Redirecting to {}", id);
-				res.set_status(StatusCode::Found);
-				res.headers_mut().set(header::Location(redirection_address(self.using_dapps_domains, id)));
-				Next::write()
-			},
 			FetchState::Error(ref mut handler) => handler.on_response(res),
 			_ => Next::end(),
 		}
@@ -224,9 +303,9 @@ impl<H: ContentValidator> server::Handler<HttpStream> for ContentFetcherHandler<
 
 	fn on_response_writable(&mut self, encoder: &mut Encoder<HttpStream>) -> Next {
 		match self.status {
+			FetchState::Done(_, _, ref mut handler) => handler.on_response_writable(encoder),
 			FetchState::Error(ref mut handler) => handler.on_response_writable(encoder),
 			_ => Next::end(),
 		}
 	}
 }
-

dapps/src/handlers/mod.rs

@@ -27,7 +27,7 @@ pub use self::auth::AuthRequiredHandler;
 pub use self::echo::EchoHandler;
 pub use self::content::ContentHandler;
 pub use self::redirect::Redirection;
-pub use self::fetch::{ContentFetcherHandler, ContentValidator};
+pub use self::fetch::{ContentFetcherHandler, ContentValidator, FetchControl};
 
 use url::Url;
 use hyper::{server, header, net, uri};

dapps/src/handlers/redirect.rs

@@ -20,15 +20,20 @@ use hyper::{header, server, Decoder, Encoder, Next};
 use hyper::net::HttpStream;
 use hyper::status::StatusCode;
 
+#[derive(Clone)]
 pub struct Redirection {
 	to_url: String
 }
 
 impl Redirection {
-	pub fn new(url: &str) -> Box<Self> {
+	pub fn new(url: &str) -> Self {
-		Box::new(Redirection {
+		Redirection {
 			to_url: url.to_owned()
-		})
+		}
+	}
+
+	pub fn boxed(url: &str) -> Box<Self> {
+		Box::new(Self::new(url))
 	}
 }
 

dapps/src/page/local.rs

@@ -21,6 +21,7 @@ use std::path::{Path, PathBuf};
 use page::handler;
 use endpoint::{Endpoint, EndpointInfo, EndpointPath, Handler};
 
+#[derive(Debug, Clone)]
 pub struct LocalPageEndpoint {
 	path: PathBuf,
 	mime: Option<String>,

dapps/src/router/mod.rs

@@ -104,7 +104,7 @@ impl<A: Authorization + 'static> server::Handler<HttpStream> for Router<A> {
 			// Redirect any GET request to home.
 			_ if *req.method() == hyper::method::Method::Get => {
 				let address = apps::redirection_address(false, self.main_page);
-				Redirection::new(address.as_str())
+				Redirection::boxed(address.as_str())
 			},
 			// RPC by default
 			_ => {