Parachain validation moved to external process (#325)

* Improved execution & tests

* Style

* Made CLI arg const

* Moved Upwards message

* CLI subcommand for validation worker

* Build halting parachain

* Build halting parachain

* Made stuff private

* Reorganized parachain tests

* Comment

* Whitespace

* Apply suggestions from code review

Co-Authored-By: Bastian Köcher <bkchr@users.noreply.github.com>

* Fixed call data size check and introduced an enum

* Apply suggestions from code review

Co-Authored-By: Bastian Köcher <bkchr@users.noreply.github.com>

polkadot/parachain/tests/adder/mod.rs

@@ -18,10 +18,8 @@
 
 use polkadot_parachain as parachain;
 
-use crate::parachain::{
-	MessageRef, UpwardMessageRef, IncomingMessage, ValidationParams,
-	wasm_executor::{Externalities, ExternalitiesError},
-};
+use crate::parachain::{IncomingMessage, ValidationParams};
+use crate::DummyExt;
 use codec::{Decode, Encode};
 
 /// Head data for this parachain.
@@ -50,16 +48,6 @@ struct AddMessage {
 	amount: u64,
 }
 
-struct DummyExt;
-impl Externalities for DummyExt {
-	fn post_message(&mut self, _message: MessageRef) -> Result<(), ExternalitiesError> {
-		Ok(())
-	}
-	fn post_upward_message(&mut self, _message: UpwardMessageRef) -> Result<(), ExternalitiesError> {
-		Ok(())
-	}
-}
-
 const TEST_CODE: &[u8] = adder::WASM_BINARY;
 
 fn hash_state(state: u64) -> [u8; 32] {
@@ -71,7 +59,7 @@ fn hash_head(head: &HeadData) -> [u8; 32] {
 }
 
 #[test]
-fn execute_good_on_parent() {
+pub fn execute_good_on_parent() {
 	let parent_head = HeadData {
 		number: 0,
 		parent_hash: [0; 32],
@@ -91,6 +79,7 @@ fn execute_good_on_parent() {
 			ingress: Vec::new(),
 		},
 		&mut DummyExt,
+		parachain::wasm_executor::ExecutionMode::RemoteTest,
 	).unwrap();
 
 	let new_head = HeadData::decode(&mut &ret.head_data[..]).unwrap();
@@ -126,6 +115,7 @@ fn execute_good_chain_on_parent() {
 				ingress: Vec::new(),
 			},
 			&mut DummyExt,
+			parachain::wasm_executor::ExecutionMode::RemoteTest,
 		).unwrap();
 
 		let new_head = HeadData::decode(&mut &ret.head_data[..]).unwrap();
@@ -161,6 +151,7 @@ fn execute_bad_on_parent() {
 			ingress: Vec::new(),
 		},
 		&mut DummyExt,
+		parachain::wasm_executor::ExecutionMode::RemoteTest,
 	).unwrap_err();
 }
 
@@ -192,6 +183,7 @@ fn processes_messages() {
 			],
 		},
 		&mut DummyExt,
+		parachain::wasm_executor::ExecutionMode::RemoteTest,
 	).unwrap();
 
 	let new_head = HeadData::decode(&mut &ret.head_data[..]).unwrap();

polkadot/parachain/tests/lib.rs

@@ -0,0 +1,44 @@
+// Copyright 2019 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+mod adder;
+mod wasm_executor;
+
+use polkadot_parachain as parachain;
+use crate::parachain::{
+	MessageRef, UpwardMessageRef,
+	wasm_executor::{Externalities, ExternalitiesError, run_worker},
+};
+
+struct DummyExt;
+impl Externalities for DummyExt {
+	fn post_message(&mut self, _message: MessageRef) -> Result<(), ExternalitiesError> {
+		Ok(())
+	}
+	fn post_upward_message(&mut self, _message: UpwardMessageRef) -> Result<(), ExternalitiesError> {
+		Ok(())
+	}
+}
+
+// This is not an actual test, but rather an entry point for out-of process WASM executor.
+// When executing tests the executor spawns currently executing binary, which happens to be test binary.
+// It then passes "validation_worker" on CLI effectivly making rust test executor to run this single test.
+#[test]
+fn validation_worker() {
+	if let Some(id) = std::env::args().find(|a| a.starts_with("/shmem_rs_")) {
+		run_worker(&id).unwrap()
+	}
+}

polkadot/parachain/tests/wasm_executor/mod.rs

@@ -0,0 +1,45 @@
+// Copyright 2019 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Basic parachain that adds a number as part of its state.
+
+use polkadot_parachain as parachain;
+use crate::{adder, DummyExt};
+use crate::parachain::ValidationParams;
+
+// Code that exposes `validate_block` and loops infinitely
+const INFINITE_LOOP_CODE: &[u8] = halt::WASM_BINARY;
+
+#[test]
+fn terminates_on_timeout() {
+	let result = parachain::wasm_executor::validate_candidate(
+		INFINITE_LOOP_CODE,
+		ValidationParams {
+			parent_head: Default::default(),
+			block_data: Vec::new(),
+			ingress: Vec::new(),
+		},
+		&mut DummyExt,
+		parachain::wasm_executor::ExecutionMode::RemoteTest,
+	);
+	match result {
+		Err(parachain::wasm_executor::Error::Timeout) => {},
+		r => panic!("{:?}", r),
+	}
+
+	// check that another parachain can validate normaly
+	adder::execute_good_on_parent();
+}