Introduce srml/im-online (#3079)

* Fix grammar and typo

* Extend network service

* Extend offchain API

* Support creating unsigned UncheckedExtrinsic

* Introduce srml/im-online

* Bump impl and spec version

* Fix web-wasm test

* Apply suggestions from code review

Remove parity-multiaddr dependency

Co-Authored-By: Pierre Krieger <pierre.krieger1708@gmail.com>

* Replace transmute with from_raw_parts

* Replace PeerId.to_string() with .to_base58()

Co-Authored-By: Pierre Krieger <pierre.krieger1708@gmail.com>

* Update Cargo.lock

* Bump impl and spec version (again)

It was updated in master in the meantime.

* Apply suggestions from code review

Co-Authored-By: Sergei Pepyakin <sergei@parity.io>

* Address comments

* Add public function is_online_in_current_session()

* Bump spec_version

* Fix doc tests

* Improve comments

* Remove superfluous line

* Name parameters consistently

* Implement comments

* Switch From to TryFrom

* Use Vec instead of HashSet

* Fix tests

* Revert me: local testing

* Fix check if already sent during session

We gossip each session, hence we need to check
if already sent in this session (not era).

* Fix typos

* Consistent terminology

* Revert "Revert me: local testing"

This reverts commit 73fbc29ff3e5ed71d99436318260b4f007e837f4.

* Introduce IsMember trait

* Implement misc comments

* Remove unused function

* Fix test

* Fix external_addresses being written

* Fix test

* Add necessary trait bound

* Do not increment version

* Update lib.rs

substrate/core/offchain/src/api.rs

@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
 
-use std::sync::Arc;
+use std::{str::FromStr, sync::Arc, convert::TryFrom};
 use client::backend::OffchainStorage;
 use crate::AuthorityKeyProvider;
 use futures::{Stream, Future, sync::mpsc};
@@ -25,6 +25,7 @@ use primitives::offchain::{
 	Externalities as OffchainExt,
 	CryptoKind, CryptoKeyId,
 	StorageKind,
+	OpaqueNetworkState, OpaquePeerId, OpaqueMultiaddr,
 };
 use primitives::crypto::{Pair, Protected};
 use primitives::{ed25519, sr25519};
@@ -33,6 +34,8 @@ use runtime_primitives::{
 	traits::{self, Extrinsic},
 };
 use transaction_pool::txpool::{Pool, ChainApi};
+use network::NetworkStateInfo;
+use network::{PeerId, Multiaddr};
 
 /// A message between the offchain extension and the processing thread.
 enum ExtMessage {
@@ -59,6 +62,7 @@ pub(crate) struct Api<Storage, KeyProvider> {
 	db: Storage,
 	keys_password: Protected<String>,
 	key_provider: KeyProvider,
+	network_state: Arc<dyn NetworkStateInfo + Send + Sync>,
 }
 
 fn unavailable_yet<R: Default>(name: &str) -> R {
@@ -158,6 +162,26 @@ impl<Storage, KeyProvider> OffchainExt for Api<Storage, KeyProvider> where
 		Ok(CryptoKeyId(id))
 	}
 
+	fn authority_pubkey(&self, kind: CryptoKind) -> Result<Vec<u8>, ()> {
+		let key = self.read_key(None, kind)?;
+		let public = match key {
+			Key::Sr25519(pair) => pair.public().encode(),
+			Key::Ed25519(pair) => pair.public().encode(),
+		};
+
+		Ok(public)
+	}
+
+	fn network_state(&self) -> Result<OpaqueNetworkState, ()> {
+		let external_addresses = self.network_state.external_addresses();
+
+		let state = NetworkState::new(
+			self.network_state.peer_id(),
+			external_addresses,
+		);
+		Ok(OpaqueNetworkState::from(state))
+	}
+
 	fn encrypt(&mut self, _key: Option<CryptoKeyId>, _kind: CryptoKind, _data: &[u8]) -> Result<Vec<u8>, ()> {
 		unavailable_yet::<()>("encrypt");
 		Err(())
@@ -285,6 +309,71 @@ impl<Storage, KeyProvider> OffchainExt for Api<Storage, KeyProvider> where
 	}
 }
 
+/// Information about the local node's network state.
+#[derive(Clone, Eq, PartialEq, Debug)]
+pub struct NetworkState {
+	peer_id: PeerId,
+	external_addresses: Vec<Multiaddr>,
+}
+
+impl NetworkState {
+	fn new(peer_id: PeerId, external_addresses: Vec<Multiaddr>) -> Self {
+		NetworkState {
+			peer_id,
+			external_addresses,
+		}
+	}
+}
+
+impl From<NetworkState> for OpaqueNetworkState {
+	fn from(state: NetworkState) -> OpaqueNetworkState {
+		let enc = Encode::encode(&state.peer_id.into_bytes());
+		let peer_id = OpaquePeerId::new(enc);
+
+		let external_addresses: Vec<OpaqueMultiaddr> = state
+			.external_addresses
+			.iter()
+			.map(|multiaddr| {
+				let e = Encode::encode(&multiaddr.to_string());
+				OpaqueMultiaddr::new(e)
+			})
+			.collect();
+
+		OpaqueNetworkState {
+			peer_id,
+			external_addresses,
+		}
+	}
+}
+
+impl TryFrom<OpaqueNetworkState> for NetworkState {
+	type Error = ();
+
+	fn try_from(state: OpaqueNetworkState) -> Result<Self, Self::Error> {
+		let inner_vec = state.peer_id.0;
+
+		let bytes: Vec<u8> = Decode::decode(&mut &inner_vec[..]).ok_or(())?;
+		let peer_id = PeerId::from_bytes(bytes).map_err(|_| ())?;
+
+		let external_addresses: Result<Vec<Multiaddr>, Self::Error> = state.external_addresses
+			.iter()
+			.map(|enc_multiaddr| -> Result<Multiaddr, Self::Error> {
+				let inner_vec = &enc_multiaddr.0;
+				let bytes = <Vec<u8>>::decode(&mut &inner_vec[..]).ok_or(())?;
+				let multiaddr_str = String::from_utf8(bytes).map_err(|_| ())?;
+				let multiaddr = Multiaddr::from_str(&multiaddr_str).map_err(|_| ())?;
+				Ok(multiaddr)
+			})
+			.collect();
+		let external_addresses = external_addresses?;
+
+		Ok(NetworkState {
+			peer_id,
+			external_addresses,
+		})
+	}
+}
+
 /// Offchain extensions implementation API
 ///
 /// This is the asynchronous processing part of the API.
@@ -302,6 +391,7 @@ impl<A: ChainApi> AsyncApi<A> {
 		keys_password: Protected<String>,
 		key_provider: P,
 		at: BlockId<A::Block>,
+		network_state: Arc<dyn NetworkStateInfo + Send + Sync>,
 	) -> (Api<S, P>, AsyncApi<A>) {
 		let (sender, rx) = mpsc::unbounded();
 
@@ -310,6 +400,7 @@ impl<A: ChainApi> AsyncApi<A> {
 			db,
 			keys_password,
 			key_provider,
+			network_state,
 		};
 
 		let async_api = AsyncApi {
@@ -355,8 +446,22 @@ impl<A: ChainApi> AsyncApi<A> {
 #[cfg(test)]
 mod tests {
 	use super::*;
+	use std::{collections::HashSet, convert::TryFrom};
 	use client_db::offchain::LocalStorage;
 	use crate::tests::TestProvider;
+	use network::PeerId;
+
+	struct MockNetworkStateInfo();
+
+	impl NetworkStateInfo for MockNetworkStateInfo {
+		fn external_addresses(&self) -> Vec<Multiaddr> {
+			Vec::new()
+		}
+
+		fn peer_id(&self) -> PeerId {
+			PeerId::random()
+		}
+	}
 
 	fn offchain_api() -> (Api<LocalStorage, TestProvider>, AsyncApi<impl ChainApi>) {
 		let _ = env_logger::try_init();
@@ -366,7 +471,8 @@ mod tests {
 			Pool::new(Default::default(), transaction_pool::ChainApi::new(client.clone()))
 		);
 
-		AsyncApi::new(pool, db, "pass".to_owned().into(), TestProvider::default(), BlockId::Number(0))
+		let mock = Arc::new(MockNetworkStateInfo());
+		AsyncApi::new(pool, db, "pass".to_owned().into(), TestProvider::default(), BlockId::Number(0), mock)
 	}
 
 	#[test]
@@ -455,4 +561,23 @@ mod tests {
 			"Invalid kind should trigger a missing key error."
 		);
 	}
+
+	#[test]
+	fn should_convert_network_states() {
+		// given
+		let state = NetworkState::new(
+			PeerId::random(),
+			vec![
+				Multiaddr::try_from("/ip4/127.0.0.1/tcp/1234".to_string()).unwrap(),
+				Multiaddr::try_from("/ip6/2601:9:4f81:9700:803e:ca65:66e8:c21").unwrap(),
+			],
+		);
+
+		// when
+		let opaque_state = OpaqueNetworkState::from(state.clone());
+		let converted_back_state = NetworkState::try_from(opaque_state).unwrap();
+
+		// then
+		assert_eq!(state, converted_back_state);
+	}
 }

substrate/core/offchain/src/lib.rs

@@ -51,6 +51,7 @@ use runtime_primitives::{
 };
 use futures::future::Future;
 use transaction_pool::txpool::{Pool, ChainApi};
+use network::NetworkStateInfo;
 
 mod api;
 
@@ -130,6 +131,7 @@ impl<Client, Storage, KeyProvider, Block> OffchainWorkers<
 		&self,
 		number: &<Block::Header as traits::Header>::Number,
 		pool: &Arc<Pool<A>>,
+		network_state: Arc<dyn NetworkStateInfo + Send + Sync>,
 	) -> impl Future<Item = (), Error = ()> where
 		A: ChainApi<Block=Block> + 'static,
 	{
@@ -145,6 +147,7 @@ impl<Client, Storage, KeyProvider, Block> OffchainWorkers<
 				self.keys_password.clone(),
 				self.authority_key.clone(),
 				at.clone(),
+				network_state.clone(),
 			);
 			debug!("Running offchain workers at {:?}", at);
 			let api = Box::new(api);
@@ -161,6 +164,20 @@ mod tests {
 	use super::*;
 	use futures::Future;
 	use primitives::{ed25519, sr25519, crypto::{TypedKey, Pair}};
+	use std::collections::HashSet;
+	use network::{Multiaddr, PeerId};
+
+	struct MockNetworkStateInfo();
+
+	impl NetworkStateInfo for MockNetworkStateInfo {
+		fn external_addresses(&self) -> Vec<Multiaddr> {
+			Vec::new()
+		}
+
+		fn peer_id(&self) -> PeerId {
+			PeerId::random()
+		}
+	}
 
 	#[derive(Clone, Default)]
 	pub(crate) struct TestProvider {
@@ -186,10 +203,11 @@ mod tests {
 		let client = Arc::new(test_client::new());
 		let pool = Arc::new(Pool::new(Default::default(), ::transaction_pool::ChainApi::new(client.clone())));
 		let db = client_db::offchain::LocalStorage::new_test();
+		let mock = Arc::new(MockNetworkStateInfo());
 
 		// when
 		let offchain = OffchainWorkers::new(client, db, TestProvider::default(), "".to_owned().into());
-		runtime.executor().spawn(offchain.on_block_imported(&0u64, &pool));
+		runtime.executor().spawn(offchain.on_block_imported(&0u64, &pool, mock.clone()));
 
 		// then
 		runtime.shutdown_on_idle().wait().unwrap();

substrate/core/offchain/src/testing.rs

@@ -31,6 +31,7 @@ use primitives::offchain::{
 	CryptoKind,
 	CryptoKeyId,
 	StorageKind,
+	OpaqueNetworkState,
 };
 
 /// Pending request.
@@ -139,6 +140,14 @@ impl offchain::Externalities for TestOffchainExt {
 		unimplemented!("not needed in tests so far")
 	}
 
+	fn network_state(&self) -> Result<OpaqueNetworkState, ()> {
+		unimplemented!("not needed in tests so far")
+	}
+
+	fn authority_pubkey(&self, _kind: CryptoKind) -> Result<Vec<u8>, ()> {
+		unimplemented!("not needed in tests so far")
+	}
+
 	fn new_crypto_key(&mut self, _crypto: CryptoKind) -> Result<CryptoKeyId, ()> {
 		unimplemented!("not needed in tests so far")
 	}