Substrate test client crate & chain subscription test (#139)

* Test client used in RPC tests.

* Use test-client for network tests.

* Expose BlockOrigin and clean up the API.

substrate/substrate/test-client/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "substrate-test-client"
+version = "0.1.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+
+[dependencies]
+substrate-bft = { path = "../bft" }
+substrate-client = { path = "../client" }
+substrate-codec = { path = "../codec" }
+substrate-executor = { path = "../executor" }
+substrate-keyring = { path = "../../substrate/keyring" }
+substrate-primitives = { path = "../primitives" }
+substrate-runtime-support = { path = "../runtime-support" }
+substrate-test-runtime = { path = "../test-runtime" }

substrate/substrate/test-client/src/client_ext.rs

@@ -0,0 +1,108 @@
+// Copyright 2018 Parity Technologies (UK) Ltd.
+// This file is part of Substrate.
+
+// Substrate is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Substrate is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Client extension for tests.
+
+use codec::Slicable;
+use client::{self, Client};
+use keyring::Keyring;
+use runtime_support::Hashable;
+use runtime::genesismap::{GenesisConfig, additional_storage_with_genesis};
+use primitives::block;
+use bft;
+use {Backend, Executor, NativeExecutor};
+
+/// Extension trait for a test client.
+pub trait TestClient {
+	/// Crates new client instance for tests.
+	fn new_for_tests() -> Self;
+
+	/// Justify and import block to the chain.
+	fn justify_and_import(&self, origin: client::BlockOrigin, block: block::Block) -> client::error::Result<()>;
+
+	/// Returns hash of the genesis block.
+	fn genesis_hash(&self) -> block::HeaderHash;
+}
+
+impl TestClient for Client<Backend, Executor> {
+	fn new_for_tests() -> Self {
+		client::new_in_mem(NativeExecutor::new(), prepare_genesis).unwrap()
+	}
+
+	fn justify_and_import(&self, origin: client::BlockOrigin, block: block::Block) -> client::error::Result<()> {
+		let justification = fake_justify(&block.header);
+		let justified = self.check_justification(block.header, justification)?;
+		self.import_block(origin, justified, Some(block.transactions))?;
+
+		Ok(())
+	}
+
+	fn genesis_hash(&self) -> block::HeaderHash {
+		self.block_hash(0).unwrap().unwrap()
+	}
+}
+
+/// Prepare fake justification for the header.
+///
+/// since we are in the client module we can create falsely justified
+/// headers.
+/// TODO: remove this in favor of custom verification pipelines for the
+/// client
+fn fake_justify(header: &block::Header) -> bft::UncheckedJustification {
+	let hash = header.blake2_256().into();
+	let authorities = vec![
+		Keyring::Alice.into(),
+		Keyring::Bob.into(),
+		Keyring::Charlie.into(),
+	];
+
+	bft::UncheckedJustification {
+		digest: hash,
+		signatures: authorities.iter().map(|key| {
+			let msg = bft::sign_message(
+				bft::generic::Vote::Commit(1, hash).into(),
+				key,
+				header.parent_hash
+			);
+
+			match msg {
+				bft::generic::LocalizedMessage::Vote(vote) => vote.signature,
+				_ => panic!("signing vote leads to signed vote"),
+			}
+		}).collect(),
+		round_number: 1,
+	}
+}
+
+fn genesis_config() -> GenesisConfig {
+	GenesisConfig::new_simple(vec![
+		Keyring::Alice.to_raw_public(),
+		Keyring::Bob.to_raw_public(),
+		Keyring::Charlie.to_raw_public()
+	], 1000)
+}
+
+fn prepare_genesis() -> (block::Header, Vec<(Vec<u8>, Vec<u8>)>) {
+	let mut storage = genesis_config().genesis_map();
+	let block = client::genesis::construct_genesis_block(&storage);
+	storage.extend(additional_storage_with_genesis(&block));
+
+	(
+		block::Header::decode(&mut block.header.encode().as_ref())
+			.expect("to_vec() always gives a valid serialisation; qed"),
+		storage.into_iter().collect()
+	)
+}

substrate/substrate/test-client/src/lib.rs

@@ -0,0 +1,54 @@
+// Copyright 2018 Parity Technologies (UK) Ltd.
+// This file is part of Substrate.
+
+// Substrate is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Substrate is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Client testing utilities.
+
+#![warn(missing_docs)]
+
+extern crate substrate_bft as bft;
+extern crate substrate_codec as codec;
+extern crate substrate_keyring as keyring;
+extern crate substrate_primitives as primitives;
+extern crate substrate_runtime_support as runtime_support;
+#[macro_use] extern crate substrate_executor as executor;
+
+pub extern crate substrate_test_runtime as runtime;
+pub extern crate substrate_client as client;
+
+mod client_ext;
+
+pub use client_ext::TestClient;
+
+mod native_executor {
+	#![allow(missing_docs)]
+	use super::runtime;
+
+	native_executor_instance!(pub NativeExecutor, runtime::api::dispatch, include_bytes!("../../test-runtime/wasm/target/wasm32-unknown-unknown/release/substrate_test_runtime.compact.wasm"));
+}
+
+/// Native executor used for tests.
+pub use self::native_executor::NativeExecutor;
+
+/// Test client database backend.
+pub type Backend = client::in_mem::Backend;
+
+/// Test client executor.
+pub type Executor = executor::NativeExecutor<NativeExecutor>;
+
+/// Creates new client instance used for tests.
+pub fn new() -> client::Client<Backend, Executor> {
+	TestClient::new_for_tests()
+}