Prepare Polkadot to be used by Cumulus

node/service/Cargo.toml

@@ -31,6 +31,7 @@ sc-chain-spec = { git = "https://github.com/paritytech/substrate", branch = "mas
 sc-executor = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sc-consensus = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sc-network = { git = "https://github.com/paritytech/substrate", branch = "master" }
+sp-storage = { git = "https://github.com/paritytech/substrate", branch = "master" }
 sp-trie = { git = "https://github.com/paritytech/substrate", branch = "master" }
 consensus_common = { package = "sp-consensus", git = "https://github.com/paritytech/substrate", branch = "master" }
 grandpa = { package = "sc-finality-grandpa", git = "https://github.com/paritytech/substrate", branch = "master" }

node/service/src/client.rs

@@ -16,38 +16,335 @@
 
 //! Polkadot Client meta trait
 
-use sp_api::{ProvideRuntimeApi, ConstructRuntimeApi, CallApiAt};
+use std::sync::Arc;
+use sp_api::{ProvideRuntimeApi, CallApiAt, NumberFor};
 use sp_blockchain::HeaderBackend;
-use sp_runtime::traits::Block as BlockT;
-use sc_client_api::{Backend as BackendT, BlockchainEvents};
+use sp_runtime::{
+	Justification, generic::{BlockId, SignedBlock}, traits::{Block as BlockT, BlakeTwo256},
+};
+use sc_client_api::{Backend as BackendT, BlockchainEvents, KeyIterator};
+use sp_storage::{StorageData, StorageKey, ChildInfo, PrefixedStorageKey};
+use polkadot_primitives::v1::{Block, ParachainHost, AccountId, Nonce, Balance};
+use consensus_common::BlockStatus;
 
-/// Polkadot client abstraction, this super trait only pulls in functionality required for
-/// polkadot internal crates like polkadot-collator.
-pub trait PolkadotClient<Block, Backend, Runtime>:
+/// A set of APIs that polkadot-like runtimes must implement.
+pub trait RuntimeApiCollection:
+	sp_transaction_pool::runtime_api::TaggedTransactionQueue<Block>
+	+ sp_api::ApiExt<Block, Error = sp_blockchain::Error>
+	+ babe_primitives::BabeApi<Block>
+	+ grandpa_primitives::GrandpaApi<Block>
+	+ ParachainHost<Block>
+	+ sp_block_builder::BlockBuilder<Block>
+	+ frame_system_rpc_runtime_api::AccountNonceApi<Block, AccountId, Nonce>
+	+ pallet_transaction_payment_rpc_runtime_api::TransactionPaymentApi<Block, Balance>
+	+ sp_api::Metadata<Block>
+	+ sp_offchain::OffchainWorkerApi<Block>
+	+ sp_session::SessionKeys<Block>
+	+ authority_discovery_primitives::AuthorityDiscoveryApi<Block>
+where
+	<Self as sp_api::ApiExt<Block>>::StateBackend: sp_api::StateBackend<BlakeTwo256>,
+{}
+
+impl<Api> RuntimeApiCollection for Api
+where
+	Api: sp_transaction_pool::runtime_api::TaggedTransactionQueue<Block>
+		+ sp_api::ApiExt<Block, Error = sp_blockchain::Error>
+		+ babe_primitives::BabeApi<Block>
+		+ grandpa_primitives::GrandpaApi<Block>
+		+ ParachainHost<Block>
+		+ sp_block_builder::BlockBuilder<Block>
+		+ frame_system_rpc_runtime_api::AccountNonceApi<Block, AccountId, Nonce>
+		+ pallet_transaction_payment_rpc_runtime_api::TransactionPaymentApi<Block, Balance>
+		+ sp_api::Metadata<Block>
+		+ sp_offchain::OffchainWorkerApi<Block>
+		+ sp_session::SessionKeys<Block>
+		+ authority_discovery_primitives::AuthorityDiscoveryApi<Block>,
+	<Self as sp_api::ApiExt<Block>>::StateBackend: sp_api::StateBackend<BlakeTwo256>,
+{}
+
+/// Trait that abstracts over all available client implementations.
+///
+/// For a concrete type there exists [`Client`].
+pub trait AbstractClient<Block, Backend>:
 	BlockchainEvents<Block> + Sized + Send + Sync
-	+ ProvideRuntimeApi<Block, Api = Runtime::RuntimeApi>
+	+ ProvideRuntimeApi<Block>
 	+ HeaderBackend<Block>
 	+ CallApiAt<
 		Block,
 		Error = sp_blockchain::Error,
-		StateBackend = Backend ::State
+		StateBackend = Backend::State
 	>
 	where
 		Block: BlockT,
 		Backend: BackendT<Block>,
-		Runtime: ConstructRuntimeApi<Block, Self>
+		Backend::State: sp_api::StateBackend<BlakeTwo256>,
+		Self::Api: RuntimeApiCollection<StateBackend = Backend::State>,
 {}
 
-impl<Block, Backend, Runtime, Client> PolkadotClient<Block, Backend, Runtime> for Client
+impl<Block, Backend, Client> AbstractClient<Block, Backend> for Client
 	where
 		Block: BlockT,
-		Runtime: ConstructRuntimeApi<Block, Self>,
 		Backend: BackendT<Block>,
-		Client: BlockchainEvents<Block> + ProvideRuntimeApi<Block, Api = Runtime::RuntimeApi> + HeaderBackend<Block>
+		Backend::State: sp_api::StateBackend<BlakeTwo256>,
+		Client: BlockchainEvents<Block> + ProvideRuntimeApi<Block> + HeaderBackend<Block>
 			+ Sized + Send + Sync
 			+ CallApiAt<
 				Block,
 				Error = sp_blockchain::Error,
-				StateBackend = Backend ::State
-			>
+				StateBackend = Backend::State
+			>,
+		Client::Api: RuntimeApiCollection<StateBackend = Backend::State>,
 {}
+
+/// Execute something with the client instance.
+///
+/// As there exist multiple chains inside Polkadot, like Polkadot itself, Kusama, Westend etc,
+/// there can exist different kinds of client types. As these client types differ in the generics
+/// that are being used, we can not easily return them from a function. For returning them from a
+/// function there exists [`Client`]. However, the problem on how to use this client instance still
+/// exists. This trait "solves" it in a dirty way. It requires a type to implement this trait and
+/// than the [`execute_with_client`](ExecuteWithClient::execute_with_client) function can be called
+/// with any possible client instance.
+///
+/// In a perfect world, we could make a closure work in this way.
+pub trait ExecuteWithClient {
+	/// The return type when calling this instance.
+	type Output;
+
+	/// Execute whatever should be executed with the given client instance.
+	fn execute_with_client<Client, Api, Backend>(self, client: Arc<Client>) -> Self::Output
+		where
+			<Api as sp_api::ApiExt<Block>>::StateBackend: sp_api::StateBackend<BlakeTwo256>,
+			Backend: sc_client_api::Backend<Block>,
+			Backend::State: sp_api::StateBackend<BlakeTwo256>,
+			Api: crate::RuntimeApiCollection<StateBackend = Backend::State>,
+			Client: AbstractClient<Block, Backend, Api = Api> + 'static;
+}
+
+/// A handle to a Polkadot client instance.
+///
+/// The Polkadot service supports multiple different runtimes (Westend, Polkadot itself, etc). As each runtime has a
+/// specialized client, we need to hide them behind a trait. This is this trait.
+///
+/// When wanting to work with the inner client, you need to use `execute_with`.
+///
+/// See [`ExecuteWithClient`](trait.ExecuteWithClient.html) for more information.
+pub trait ClientHandle {
+	/// Execute the given something with the client.
+	fn execute_with<T: ExecuteWithClient>(&self, t: T) -> T::Output;
+}
+
+/// A client instance of Polkadot.
+///
+/// See [`ExecuteWithClient`] for more information.
+#[derive(Clone)]
+pub enum Client {
+	Polkadot(Arc<crate::FullClient<polkadot_runtime::RuntimeApi, crate::PolkadotExecutor>>),
+	Westend(Arc<crate::FullClient<westend_runtime::RuntimeApi, crate::WestendExecutor>>),
+	Kusama(Arc<crate::FullClient<kusama_runtime::RuntimeApi, crate::KusamaExecutor>>),
+}
+
+impl ClientHandle for Client {
+	fn execute_with<T: ExecuteWithClient>(&self, t: T) -> T::Output {
+		match self {
+			Self::Polkadot(client) => {
+				T::execute_with_client::<_, _, crate::FullBackend>(t, client.clone())
+			},
+			Self::Westend(client) => {
+				T::execute_with_client::<_, _, crate::FullBackend>(t, client.clone())
+			},
+			Self::Kusama(client) => {
+				T::execute_with_client::<_, _, crate::FullBackend>(t, client.clone())
+			},
+		}
+	}
+}
+
+impl sc_client_api::UsageProvider<Block> for Client {
+	fn usage_info(&self) -> sc_client_api::ClientInfo<Block> {
+		match self {
+			Self::Polkadot(client) => client.usage_info(),
+			Self::Westend(client) => client.usage_info(),
+			Self::Kusama(client) => client.usage_info(),
+		}
+	}
+}
+
+impl sc_client_api::BlockBackend<Block> for Client {
+	fn block_body(
+		&self,
+		id: &BlockId<Block>
+	) -> sp_blockchain::Result<Option<Vec<<Block as BlockT>::Extrinsic>>> {
+		match self {
+			Self::Polkadot(client) => client.block_body(id),
+			Self::Westend(client) => client.block_body(id),
+			Self::Kusama(client) => client.block_body(id),
+		}
+	}
+
+	fn block(&self, id: &BlockId<Block>) -> sp_blockchain::Result<Option<SignedBlock<Block>>> {
+		match self {
+			Self::Polkadot(client) => client.block(id),
+			Self::Westend(client) => client.block(id),
+			Self::Kusama(client) => client.block(id),
+		}
+	}
+
+	fn block_status(&self, id: &BlockId<Block>) -> sp_blockchain::Result<BlockStatus> {
+		match self {
+			Self::Polkadot(client) => client.block_status(id),
+			Self::Westend(client) => client.block_status(id),
+			Self::Kusama(client) => client.block_status(id),
+		}
+	}
+
+	fn justification(
+		&self,
+		id: &BlockId<Block>
+	) -> sp_blockchain::Result<Option<Justification>> {
+		match self {
+			Self::Polkadot(client) => client.justification(id),
+			Self::Westend(client) => client.justification(id),
+			Self::Kusama(client) => client.justification(id),
+		}
+	}
+
+	fn block_hash(
+		&self,
+		number: NumberFor<Block>
+	) -> sp_blockchain::Result<Option<<Block as BlockT>::Hash>> {
+		match self {
+			Self::Polkadot(client) => client.block_hash(number),
+			Self::Westend(client) => client.block_hash(number),
+			Self::Kusama(client) => client.block_hash(number),
+		}
+	}
+}
+
+impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
+	fn storage(
+		&self,
+		id: &BlockId<Block>,
+		key: &StorageKey,
+	) -> sp_blockchain::Result<Option<StorageData>> {
+		match self {
+			Self::Polkadot(client) => client.storage(id, key),
+			Self::Westend(client) => client.storage(id, key),
+			Self::Kusama(client) => client.storage(id, key),
+		}
+	}
+
+	fn storage_keys(
+		&self,
+		id: &BlockId<Block>,
+		key_prefix: &StorageKey,
+	) -> sp_blockchain::Result<Vec<StorageKey>> {
+		match self {
+			Self::Polkadot(client) => client.storage_keys(id, key_prefix),
+			Self::Westend(client) => client.storage_keys(id, key_prefix),
+			Self::Kusama(client) => client.storage_keys(id, key_prefix),
+		}
+	}
+
+	fn storage_hash(
+		&self,
+		id: &BlockId<Block>,
+		key: &StorageKey,
+	) -> sp_blockchain::Result<Option<<Block as BlockT>::Hash>> {
+		match self {
+			Self::Polkadot(client) => client.storage_hash(id, key),
+			Self::Westend(client) => client.storage_hash(id, key),
+			Self::Kusama(client) => client.storage_hash(id, key),
+		}
+	}
+
+	fn storage_pairs(
+		&self,
+		id: &BlockId<Block>,
+		key_prefix: &StorageKey,
+	) -> sp_blockchain::Result<Vec<(StorageKey, StorageData)>> {
+		match self {
+			Self::Polkadot(client) => client.storage_pairs(id, key_prefix),
+			Self::Westend(client) => client.storage_pairs(id, key_prefix),
+			Self::Kusama(client) => client.storage_pairs(id, key_prefix),
+		}
+	}
+
+	fn storage_keys_iter<'a>(
+		&self,
+		id: &BlockId<Block>,
+		prefix: Option<&'a StorageKey>,
+		start_key: Option<&StorageKey>,
+	) -> sp_blockchain::Result<KeyIterator<'a, <crate::FullBackend as sc_client_api::Backend<Block>>::State, Block>> {
+		match self {
+			Self::Polkadot(client) => client.storage_keys_iter(id, prefix, start_key),
+			Self::Westend(client) => client.storage_keys_iter(id, prefix, start_key),
+			Self::Kusama(client) => client.storage_keys_iter(id, prefix, start_key),
+		}
+	}
+
+	fn child_storage(
+		&self,
+		id: &BlockId<Block>,
+		child_info: &ChildInfo,
+		key: &StorageKey,
+	) -> sp_blockchain::Result<Option<StorageData>> {
+		match self {
+			Self::Polkadot(client) => client.child_storage(id, child_info, key),
+			Self::Westend(client) => client.child_storage(id, child_info, key),
+			Self::Kusama(client) => client.child_storage(id, child_info, key),
+		}
+	}
+
+	fn child_storage_keys(
+		&self,
+		id: &BlockId<Block>,
+		child_info: &ChildInfo,
+		key_prefix: &StorageKey,
+	) -> sp_blockchain::Result<Vec<StorageKey>> {
+		match self {
+			Self::Polkadot(client) => client.child_storage_keys(id, child_info, key_prefix),
+			Self::Westend(client) => client.child_storage_keys(id, child_info, key_prefix),
+			Self::Kusama(client) => client.child_storage_keys(id, child_info, key_prefix),
+		}
+	}
+
+	fn child_storage_hash(
+		&self,
+		id: &BlockId<Block>,
+		child_info: &ChildInfo,
+		key: &StorageKey,
+	) -> sp_blockchain::Result<Option<<Block as BlockT>::Hash>> {
+		match self {
+			Self::Polkadot(client) => client.child_storage_hash(id, child_info, key),
+			Self::Westend(client) => client.child_storage_hash(id, child_info, key),
+			Self::Kusama(client) => client.child_storage_hash(id, child_info, key),
+		}
+	}
+
+	fn max_key_changes_range(
+		&self,
+		first: NumberFor<Block>,
+		last: BlockId<Block>,
+	) -> sp_blockchain::Result<Option<(NumberFor<Block>, BlockId<Block>)>> {
+		match self {
+			Self::Polkadot(client) => client.max_key_changes_range(first, last),
+			Self::Westend(client) => client.max_key_changes_range(first, last),
+			Self::Kusama(client) => client.max_key_changes_range(first, last),
+		}
+	}
+
+	fn key_changes(
+		&self,
+		first: NumberFor<Block>,
+		last: BlockId<Block>,
+		storage_key: Option<&PrefixedStorageKey>,
+		key: &StorageKey,
+	) -> sp_blockchain::Result<Vec<(NumberFor<Block>, u32)>> {
+		match self {
+			Self::Polkadot(client) => client.key_changes(first, last, storage_key, key),
+			Self::Westend(client) => client.key_changes(first, last, storage_key, key),
+			Self::Kusama(client) => client.key_changes(first, last, storage_key, key),
+		}
+	}
+}