DB-based blockchain data cache for light nodes

polkadot/service/src/components.rs

@@ -116,15 +116,19 @@ impl Components for FullComponents {
 pub struct LightComponents;
 
 impl Components for LightComponents {
-	type Backend = client::light::Backend<Block>;
+	type Backend = client::light::backend::Backend<client_db::light::LightStorage<Block>, network::OnDemand<Block, network::Service<Block>>>;
 	type Api = polkadot_api::light::RemotePolkadotApiWrapper<Self::Backend, Self::Executor>;
-	type Executor = client::RemoteCallExecutor<client::light::Backend<Block>, network::OnDemand<Block, network::Service<Block>>>;
+	type Executor = client::light::call_executor::RemoteCallExecutor<
+		client::light::blockchain::Blockchain<client_db::light::LightStorage<Block>, network::OnDemand<Block, network::Service<Block>>>,
+		network::OnDemand<Block, network::Service<Block>>>;
 
-	fn build_client(&self, _settings: client_db::DatabaseSettings, executor: CodeExecutor, genesis_storage: MakeStorage)
+	fn build_client(&self, db_settings: client_db::DatabaseSettings, executor: CodeExecutor, genesis_storage: MakeStorage)
 		-> Result<(Arc<client::Client<Self::Backend, Self::Executor, Block>>, Option<Arc<network::OnDemand<Block, network::Service<Block>>>>), error::Error> {
-		let client_backend = client::light::new_light_backend();
-		let fetch_checker = Arc::new(client::light::new_fetch_checker(client_backend.clone(), executor));
+		let db_storage = client_db::light::LightStorage::new(db_settings)?;
+		let light_blockchain = client::light::new_light_blockchain(db_storage);
+		let fetch_checker = Arc::new(client::light::new_fetch_checker(light_blockchain.clone(), executor));
 		let fetcher = Arc::new(network::OnDemand::new(fetch_checker));
+		let client_backend = client::light::new_light_backend(light_blockchain, fetcher.clone());
 		let client = client::light::new_light(client_backend, fetcher.clone(), genesis_storage)?;
 		Ok((Arc::new(client), Some(fetcher)))
 	}

polkadot/service/src/lib.rs

@@ -136,7 +136,7 @@ impl<Components> Service<Components>
 			},
 			network_config: config.network,
 			chain: client.clone(),
-			on_demand: on_demand.clone().map(|d| d as Arc<network::OnDemandService>),
+			on_demand: on_demand.clone().map(|d| d as Arc<network::OnDemandService<Block>>),
 			transaction_pool: transaction_pool_adapter,
 		};
 		let network = network::Service::new(network_params)?;

substrate/bft/src/lib.rs

@@ -149,7 +149,7 @@ pub trait Proposer<B: Block> {
 /// Block import trait.
 pub trait BlockImport<B: Block> {
 	/// Import a block alongside its corresponding justification.
-	fn import_block(&self, block: B, justification: Justification<B::Hash>);
+	fn import_block(&self, block: B, justification: Justification<B::Hash>, authorities: &[AuthorityId]);
 }
 
 /// Trait for getting the authorities at a given block.
@@ -269,7 +269,8 @@ impl<B, P, I, InStream, OutSink> Future for BftFuture<B, P, I, InStream, OutSink
 			info!(target: "bft", "Importing block #{} ({}) directly from BFT consensus",
 				justified_block.header().number(), justified_block.hash());
 
-			self.import.import_block(justified_block, committed.justification)
+			self.import.import_block(justified_block, committed.justification,
+				&self.inner.context().authorities)
 		}
 
 		Ok(Async::Ready(()))
@@ -608,7 +609,7 @@ mod tests {
 	}
 
 	impl BlockImport<TestBlock> for FakeClient {
-		fn import_block(&self, block: TestBlock, _justification: Justification<H256>) {
+		fn import_block(&self, block: TestBlock, _justification: Justification<H256>, _authorities: &[AuthorityId]) {
 			assert!(self.imported_heights.lock().insert(block.header.number))
 		}
 	}