Upgrade pallets to FRAMEv2 (#404)

* Upgrade parachain info pallet to FRAMEv2 * Upgrade parachain system pallet to FRAMEv2 * Use Pallet<T> instead of Module<T> * Upgrade XCMP queue pallet to FRAMEv2 * Correctly specify the metadata for events in xcmp-queue pallet * Apply suggestions from code review * Update pallets/parachain-system/src/tests.rs Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>
2026-04-30 18:57:57 +00:00 · 2021-05-08 13:18:01 -07:00
parent 2641c5b830
commit 647a9e6df9
6 changed files with 1691 additions and 1500 deletions
@@ -0,0 +1,935 @@
+// Copyright 2020 Parity Technologies (UK) Ltd.
+// This file is part of Cumulus.
+
+// Cumulus 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.
+
+// Cumulus 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 Cumulus.  If not, see <http://www.gnu.org/licenses/>.
+use super::*;
+
+use codec::Encode;
+use cumulus_primitives_core::{
+	AbridgedHrmpChannel, InboundDownwardMessage, InboundHrmpMessage, PersistedValidationData,
+	relay_chain::BlockNumber as RelayBlockNumber,
+};
+use cumulus_test_relay_sproof_builder::RelayStateSproofBuilder;
+use frame_support::{
+	assert_ok,
+	dispatch::UnfilteredDispatchable,
+	parameter_types,
+	storage,
+	traits::{OnFinalize, OnInitialize},
+	weights::Weight,
+	inherent::{InherentData, ProvideInherent},
+};
+use frame_system::{InitKind, RawOrigin};
+use hex_literal::hex;
+use relay_chain::v1::HrmpChannelId;
+use sp_core::H256;
+use sp_runtime::{testing::Header, traits::IdentityLookup};
+use sp_version::RuntimeVersion;
+use std::cell::RefCell;
+
+use crate as parachain_system;
+
+type UncheckedExtrinsic = frame_system::mocking::MockUncheckedExtrinsic<Test>;
+type Block = frame_system::mocking::MockBlock<Test>;
+
+frame_support::construct_runtime!(
+	pub enum Test where
+		Block = Block,
+		NodeBlock = Block,
+		UncheckedExtrinsic = UncheckedExtrinsic,
+	{
+		System: frame_system::{Pallet, Call, Config, Storage, Event<T>},
+		ParachainSystem: parachain_system::{Pallet, Call, Storage, Event<T>},
+	}
+);
+
+parameter_types! {
+	pub const BlockHashCount: u64 = 250;
+	pub Version: RuntimeVersion = RuntimeVersion {
+		spec_name: sp_version::create_runtime_str!("test"),
+		impl_name: sp_version::create_runtime_str!("system-test"),
+		authoring_version: 1,
+		spec_version: 1,
+		impl_version: 1,
+		apis: sp_version::create_apis_vec!([]),
+		transaction_version: 1,
+	};
+	pub const ParachainId: ParaId = ParaId::new(200);
+	pub const ReservedXcmpWeight: Weight = 0;
+	pub const ReservedDmpWeight: Weight = 0;
+}
+impl frame_system::Config for Test {
+	type Origin = Origin;
+	type Call = Call;
+	type Index = u64;
+	type BlockNumber = u64;
+	type Hash = H256;
+	type Hashing = BlakeTwo256;
+	type AccountId = u64;
+	type Lookup = IdentityLookup<Self::AccountId>;
+	type Header = Header;
+	type Event = Event;
+	type BlockHashCount = BlockHashCount;
+	type BlockLength = ();
+	type BlockWeights = ();
+	type Version = Version;
+	type PalletInfo = PalletInfo;
+	type AccountData = ();
+	type OnNewAccount = ();
+	type OnKilledAccount = ();
+	type DbWeight = ();
+	type BaseCallFilter = ();
+	type SystemWeightInfo = ();
+	type SS58Prefix = ();
+	type OnSetCode = ParachainSetCode<Self>;
+}
+impl Config for Test {
+	type Event = Event;
+	type OnValidationData = ();
+	type SelfParaId = ParachainId;
+	type OutboundXcmpMessageSource = FromThreadLocal;
+	type DmpMessageHandler = SaveIntoThreadLocal;
+	type ReservedDmpWeight = ReservedDmpWeight;
+	type XcmpMessageHandler = SaveIntoThreadLocal;
+	type ReservedXcmpWeight = ReservedXcmpWeight;
+}
+
+pub struct FromThreadLocal;
+pub struct SaveIntoThreadLocal;
+
+std::thread_local! {
+	static HANDLED_DMP_MESSAGES: RefCell<Vec<(relay_chain::BlockNumber, Vec<u8>)>> = RefCell::new(Vec::new());
+	static HANDLED_XCMP_MESSAGES: RefCell<Vec<(ParaId, relay_chain::BlockNumber, Vec<u8>)>> = RefCell::new(Vec::new());
+	static SENT_MESSAGES: RefCell<Vec<(ParaId, Vec<u8>)>> = RefCell::new(Vec::new());
+}
+
+fn send_message(
+	dest: ParaId,
+	message: Vec<u8>,
+) {
+	SENT_MESSAGES.with(|m| m.borrow_mut().push((dest, message)));
+}
+
+impl XcmpMessageSource for FromThreadLocal {
+	fn take_outbound_messages(maximum_channels: usize) -> Vec<(ParaId, Vec<u8>)> {
+		let mut ids = std::collections::BTreeSet::<ParaId>::new();
+		let mut taken = 0;
+		let mut result = Vec::new();
+		SENT_MESSAGES.with(|ms| ms.borrow_mut()
+			.retain(|m| {
+				let status = <Pallet::<Test> as GetChannelInfo>::get_channel_status(m.0);
+				let ready = matches!(status, ChannelStatus::Ready(..));
+				if ready && !ids.contains(&m.0) && taken < maximum_channels {
+					ids.insert(m.0);
+					taken += 1;
+					result.push(m.clone());
+					false
+				} else {
+					true
+				}
+			})
+		);
+		result
+	}
+}
+
+impl DmpMessageHandler for SaveIntoThreadLocal {
+	fn handle_dmp_messages(
+		iter: impl Iterator<Item=(RelayBlockNumber, Vec<u8>)>,
+		_max_weight: Weight,
+	) -> Weight {
+		HANDLED_DMP_MESSAGES.with(|m| {
+			for i in iter {
+				m.borrow_mut().push(i);
+			}
+			0
+		})
+	}
+}
+
+impl XcmpMessageHandler for SaveIntoThreadLocal {
+	fn handle_xcmp_messages<'a, I: Iterator<Item=(ParaId, RelayBlockNumber, &'a [u8])>>(
+		iter: I,
+		_max_weight: Weight,
+	) -> Weight {
+		HANDLED_XCMP_MESSAGES.with(|m| {
+			for (sender, sent_at, message) in iter {
+				m.borrow_mut().push((sender, sent_at, message.to_vec()));
+			}
+			0
+		})
+	}
+}
+
+// This function basically just builds a genesis storage key/value store according to
+// our desired mockup.
+fn new_test_ext() -> sp_io::TestExternalities {
+	HANDLED_DMP_MESSAGES.with(|m| m.borrow_mut().clear());
+	HANDLED_XCMP_MESSAGES.with(|m| m.borrow_mut().clear());
+
+	frame_system::GenesisConfig::default()
+		.build_storage::<Test>()
+		.unwrap()
+		.into()
+}
+
+struct CallInWasm(Vec<u8>);
+
+impl sp_core::traits::CallInWasm for CallInWasm {
+	fn call_in_wasm(
+		&self,
+		_wasm_code: &[u8],
+		_code_hash: Option<Vec<u8>>,
+		_method: &str,
+		_call_data: &[u8],
+		_ext: &mut dyn sp_externalities::Externalities,
+		_missing_host_functions: sp_core::traits::MissingHostFunctions,
+	) -> Result<Vec<u8>, String> {
+		Ok(self.0.clone())
+	}
+}
+
+fn wasm_ext() -> sp_io::TestExternalities {
+	let version = RuntimeVersion {
+		spec_name: "test".into(),
+		spec_version: 2,
+		impl_version: 1,
+		..Default::default()
+	};
+	let call_in_wasm = CallInWasm(version.encode());
+
+	let mut ext = new_test_ext();
+	ext.register_extension(sp_core::traits::CallInWasmExt::new(call_in_wasm));
+	ext
+}
+
+struct BlockTest {
+	n: <Test as frame_system::Config>::BlockNumber,
+	within_block: Box<dyn Fn()>,
+	after_block: Option<Box<dyn Fn()>>,
+}
+
+/// BlockTests exist to test blocks with some setup: we have to assume that
+/// `validate_block` will mutate and check storage in certain predictable
+/// ways, for example, and we want to always ensure that tests are executed
+/// in the context of some particular block number.
+#[derive(Default)]
+struct BlockTests {
+	tests: Vec<BlockTest>,
+	pending_upgrade: Option<RelayChainBlockNumber>,
+	ran: bool,
+	relay_sproof_builder_hook:
+		Option<Box<dyn Fn(&BlockTests, RelayChainBlockNumber, &mut RelayStateSproofBuilder)>>,
+	persisted_validation_data_hook:
+		Option<Box<dyn Fn(&BlockTests, RelayChainBlockNumber, &mut PersistedValidationData)>>,
+	inherent_data_hook:
+		Option<Box<dyn Fn(&BlockTests, RelayChainBlockNumber, &mut ParachainInherentData)>>,
+}
+
+impl BlockTests {
+	fn new() -> BlockTests {
+		Default::default()
+	}
+
+	fn add_raw(mut self, test: BlockTest) -> Self {
+		self.tests.push(test);
+		self
+	}
+
+	fn add<F>(self, n: <Test as frame_system::Config>::BlockNumber, within_block: F) -> Self
+	where
+		F: 'static + Fn(),
+	{
+		self.add_raw(BlockTest {
+			n,
+			within_block: Box::new(within_block),
+			after_block: None,
+		})
+	}
+
+	fn add_with_post_test<F1, F2>(
+		self,
+		n: <Test as frame_system::Config>::BlockNumber,
+		within_block: F1,
+		after_block: F2,
+	) -> Self
+	where
+		F1: 'static + Fn(),
+		F2: 'static + Fn(),
+	{
+		self.add_raw(BlockTest {
+			n,
+			within_block: Box::new(within_block),
+			after_block: Some(Box::new(after_block)),
+		})
+	}
+
+	fn with_relay_sproof_builder<F>(mut self, f: F) -> Self
+	where
+		F: 'static + Fn(&BlockTests, RelayChainBlockNumber, &mut RelayStateSproofBuilder),
+	{
+		self.relay_sproof_builder_hook = Some(Box::new(f));
+		self
+	}
+
+	#[allow(dead_code)] // might come in handy in future. If now is future and it still hasn't - feel free.
+	fn with_validation_data<F>(mut self, f: F) -> Self
+	where
+		F: 'static + Fn(&BlockTests, RelayChainBlockNumber, &mut PersistedValidationData),
+	{
+		self.persisted_validation_data_hook = Some(Box::new(f));
+		self
+	}
+
+	fn with_inherent_data<F>(mut self, f: F) -> Self
+	where
+		F: 'static + Fn(&BlockTests, RelayChainBlockNumber, &mut ParachainInherentData),
+	{
+		self.inherent_data_hook = Some(Box::new(f));
+		self
+	}
+
+	fn run(&mut self) {
+		self.ran = true;
+		wasm_ext().execute_with(|| {
+			for BlockTest {
+				n,
+				within_block,
+				after_block,
+			} in self.tests.iter()
+			{
+				// clear pending updates, as applicable
+				if let Some(upgrade_block) = self.pending_upgrade {
+					if n >= &upgrade_block.into() {
+						self.pending_upgrade = None;
+					}
+				}
+
+				// begin initialization
+				System::initialize(
+					&n,
+					&Default::default(),
+					&Default::default(),
+					InitKind::Full,
+				);
+
+				// now mess with the storage the way validate_block does
+				let mut sproof_builder = RelayStateSproofBuilder::default();
+				if let Some(ref hook) = self.relay_sproof_builder_hook {
+					hook(self, *n as RelayChainBlockNumber, &mut sproof_builder);
+				}
+				let (relay_parent_storage_root, relay_chain_state) =
+					sproof_builder.into_state_root_and_proof();
+				let mut vfp = PersistedValidationData {
+					relay_parent_number: *n as RelayChainBlockNumber,
+					relay_parent_storage_root,
+					..Default::default()
+				};
+				if let Some(ref hook) = self.persisted_validation_data_hook {
+					hook(self, *n as RelayChainBlockNumber, &mut vfp);
+				}
+
+				<ValidationData<Test>>::put(&vfp);
+				storage::unhashed::kill(NEW_VALIDATION_CODE);
+
+				// It is insufficient to push the validation function params
+				// to storage; they must also be included in the inherent data.
+				let inherent_data = {
+					let mut inherent_data = InherentData::default();
+					let mut system_inherent_data = ParachainInherentData {
+						validation_data: vfp.clone(),
+						relay_chain_state,
+						downward_messages: Default::default(),
+						horizontal_messages: Default::default(),
+					};
+					if let Some(ref hook) = self.inherent_data_hook {
+						hook(self, *n as RelayChainBlockNumber, &mut system_inherent_data);
+					}
+					inherent_data
+						.put_data(
+							cumulus_primitives_parachain_inherent::INHERENT_IDENTIFIER,
+							&system_inherent_data,
+						)
+						.expect("failed to put VFP inherent");
+					inherent_data
+				};
+
+				// execute the block
+				ParachainSystem::on_initialize(*n);
+				ParachainSystem::create_inherent(&inherent_data)
+					.expect("got an inherent")
+					.dispatch_bypass_filter(RawOrigin::None.into())
+					.expect("dispatch succeeded");
+				within_block();
+				ParachainSystem::on_finalize(*n);
+
+				// did block execution set new validation code?
+				if storage::unhashed::exists(NEW_VALIDATION_CODE) {
+					if self.pending_upgrade.is_some() {
+						panic!("attempted to set validation code while upgrade was pending");
+					}
+				}
+
+				// clean up
+				System::finalize();
+				if let Some(after_block) = after_block {
+					after_block();
+				}
+			}
+		});
+	}
+}
+
+impl Drop for BlockTests {
+	fn drop(&mut self) {
+		if !self.ran {
+			self.run();
+		}
+	}
+}
+
+#[test]
+#[should_panic]
+fn block_tests_run_on_drop() {
+	BlockTests::new().add(123, || {
+		panic!("if this test passes, block tests run properly")
+	});
+}
+
+#[test]
+fn events() {
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, _, builder| {
+			builder.host_config.validation_upgrade_delay = 1000;
+		})
+		.add_with_post_test(
+			123,
+			|| {
+				assert_ok!(System::set_code(
+					RawOrigin::Root.into(),
+					Default::default()
+				));
+			},
+			|| {
+				let events = System::events();
+				assert_eq!(
+					events[0].event,
+					Event::parachain_system(crate::Event::ValidationFunctionStored(1123).into())
+				);
+			},
+		)
+		.add_with_post_test(
+			1234,
+			|| {},
+			|| {
+				let events = System::events();
+				assert_eq!(
+					events[0].event,
+					Event::parachain_system(crate::Event::ValidationFunctionApplied(1234).into())
+				);
+			},
+		);
+}
+
+#[test]
+fn non_overlapping() {
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, _, builder| {
+			builder.host_config.validation_upgrade_delay = 1000;
+		})
+		.add(123, || {
+			assert_ok!(System::set_code(
+				RawOrigin::Root.into(),
+				Default::default()
+			));
+		})
+		.add(234, || {
+			assert_eq!(
+				System::set_code(RawOrigin::Root.into(), Default::default()),
+				Err(Error::<Test>::OverlappingUpgrades.into()),
+			)
+		});
+}
+
+#[test]
+fn manipulates_storage() {
+	BlockTests::new()
+		.add(123, || {
+			assert!(
+				!<PendingValidationFunction<Test>>::exists(),
+				"validation function must not exist yet"
+			);
+			assert_ok!(System::set_code(
+				RawOrigin::Root.into(),
+				Default::default()
+			));
+			assert!(
+				<PendingValidationFunction<Test>>::exists(),
+				"validation function must now exist"
+			);
+		})
+		.add_with_post_test(
+			1234,
+			|| {},
+			|| {
+				assert!(
+					!<PendingValidationFunction<Test>>::exists(),
+					"validation function must have been unset"
+				);
+			},
+		);
+}
+
+#[test]
+fn checks_size() {
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, _, builder| {
+			builder.host_config.max_code_size = 8;
+		})
+		.add(123, || {
+			assert_eq!(
+				System::set_code(RawOrigin::Root.into(), vec![0; 64]),
+				Err(Error::<Test>::TooBig.into()),
+			);
+		});
+}
+
+#[test]
+fn send_upward_message_num_per_candidate() {
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, _, sproof| {
+			sproof.host_config.max_upward_message_num_per_candidate = 1;
+			sproof.relay_dispatch_queue_size = None;
+		})
+		.add_with_post_test(
+			1,
+			|| {
+				ParachainSystem::send_upward_message(b"Mr F was here".to_vec()).unwrap();
+				ParachainSystem::send_upward_message(b"message 2".to_vec()).unwrap();
+			},
+			|| {
+				let v: Option<Vec<Vec<u8>>> =
+					storage::unhashed::get(well_known_keys::UPWARD_MESSAGES);
+				assert_eq!(v, Some(vec![b"Mr F was here".to_vec()]),);
+			},
+		)
+		.add_with_post_test(
+			2,
+			|| { /* do nothing within block */ },
+			|| {
+				let v: Option<Vec<Vec<u8>>> =
+					storage::unhashed::get(well_known_keys::UPWARD_MESSAGES);
+				assert_eq!(v, Some(vec![b"message 2".to_vec()]),);
+			},
+		);
+}
+
+#[test]
+fn send_upward_message_relay_bottleneck() {
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, relay_block_num, sproof| {
+			sproof.host_config.max_upward_message_num_per_candidate = 2;
+			sproof.host_config.max_upward_queue_count = 5;
+
+			match relay_block_num {
+				1 => sproof.relay_dispatch_queue_size = Some((5, 0)),
+				2 => sproof.relay_dispatch_queue_size = Some((4, 0)),
+				_ => unreachable!(),
+			}
+		})
+		.add_with_post_test(
+			1,
+			|| {
+				ParachainSystem::send_upward_message(vec![0u8; 8]).unwrap();
+			},
+			|| {
+				// The message won't be sent because there is already one message in queue.
+				let v: Option<Vec<Vec<u8>>> =
+					storage::unhashed::get(well_known_keys::UPWARD_MESSAGES);
+				assert_eq!(v, Some(vec![]),);
+			},
+		)
+		.add_with_post_test(
+			2,
+			|| { /* do nothing within block */ },
+			|| {
+				let v: Option<Vec<Vec<u8>>> =
+					storage::unhashed::get(well_known_keys::UPWARD_MESSAGES);
+				assert_eq!(v, Some(vec![vec![0u8; 8]]),);
+			},
+		);
+}
+
+#[test]
+fn send_hrmp_message_buffer_channel_close() {
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, relay_block_num, sproof| {
+			//
+			// Base case setup
+			//
+			sproof.para_id = ParaId::from(200);
+			sproof.hrmp_egress_channel_index = Some(vec![ParaId::from(300), ParaId::from(400)]);
+			sproof.hrmp_channels.insert(
+				HrmpChannelId {
+					sender: ParaId::from(200),
+					recipient: ParaId::from(300),
+				},
+				AbridgedHrmpChannel {
+					max_capacity: 1,
+					msg_count: 1, // <- 1/1 means the channel is full
+					max_total_size: 1024,
+					max_message_size: 8,
+					total_size: 0,
+					mqc_head: Default::default(),
+				},
+			);
+			sproof.hrmp_channels.insert(
+				HrmpChannelId {
+					sender: ParaId::from(200),
+					recipient: ParaId::from(400),
+				},
+				AbridgedHrmpChannel {
+					max_capacity: 1,
+					msg_count: 1,
+					max_total_size: 1024,
+					max_message_size: 8,
+					total_size: 0,
+					mqc_head: Default::default(),
+				},
+			);
+
+			//
+			// Adjustment according to block
+			//
+			match relay_block_num {
+				1 => {}
+				2 => {}
+				3 => {
+					// The channel 200->400 ceases to exist at the relay chain block 3
+					sproof
+						.hrmp_egress_channel_index
+						.as_mut()
+						.unwrap()
+						.retain(|n| n != &ParaId::from(400));
+					sproof.hrmp_channels.remove(&HrmpChannelId {
+						sender: ParaId::from(200),
+						recipient: ParaId::from(400),
+					});
+
+					// We also free up space for a message in the 200->300 channel.
+					sproof
+						.hrmp_channels
+						.get_mut(&HrmpChannelId {
+							sender: ParaId::from(200),
+							recipient: ParaId::from(300),
+						})
+						.unwrap()
+						.msg_count = 0;
+				}
+				_ => unreachable!(),
+			}
+		})
+		.add_with_post_test(
+			1,
+			|| {
+				send_message(
+					ParaId::from(300),
+					b"1".to_vec(),
+				);
+				send_message(
+					ParaId::from(400),
+					b"2".to_vec(),
+				);
+			},
+			|| {},
+		)
+		.add_with_post_test(
+			2,
+			|| {},
+			|| {
+				// both channels are at capacity so we do not expect any messages.
+				let v: Option<Vec<OutboundHrmpMessage>> =
+					storage::unhashed::get(well_known_keys::HRMP_OUTBOUND_MESSAGES);
+				assert_eq!(v, Some(vec![]));
+			},
+		)
+		.add_with_post_test(
+			3,
+			|| {},
+			|| {
+				let v: Option<Vec<OutboundHrmpMessage>> =
+					storage::unhashed::get(well_known_keys::HRMP_OUTBOUND_MESSAGES);
+				assert_eq!(
+					v,
+					Some(vec![OutboundHrmpMessage {
+						recipient: ParaId::from(300),
+						data: b"1".to_vec(),
+					}])
+				);
+			},
+		);
+}
+
+#[test]
+fn message_queue_chain() {
+	assert_eq!(MessageQueueChain::default().head(), H256::zero());
+
+	// Note that the resulting hashes are the same for HRMP and DMP. That's because even though
+	// the types are nominally different, they have the same structure and computation of the
+	// new head doesn't differ.
+	//
+	// These cases are taken from https://github.com/paritytech/polkadot/pull/2351
+	assert_eq!(
+		MessageQueueChain::default()
+			.extend_downward(&InboundDownwardMessage {
+				sent_at: 2,
+				msg: vec![1, 2, 3],
+			})
+			.extend_downward(&InboundDownwardMessage {
+				sent_at: 3,
+				msg: vec![4, 5, 6],
+			})
+			.head(),
+		hex!["88dc00db8cc9d22aa62b87807705831f164387dfa49f80a8600ed1cbe1704b6b"].into(),
+	);
+	assert_eq!(
+		MessageQueueChain::default()
+			.extend_hrmp(&InboundHrmpMessage {
+				sent_at: 2,
+				data: vec![1, 2, 3],
+			})
+			.extend_hrmp(&InboundHrmpMessage {
+				sent_at: 3,
+				data: vec![4, 5, 6],
+			})
+			.head(),
+		hex!["88dc00db8cc9d22aa62b87807705831f164387dfa49f80a8600ed1cbe1704b6b"].into(),
+	);
+}
+
+#[test]
+fn receive_dmp() {
+	lazy_static::lazy_static! {
+		static ref MSG: InboundDownwardMessage = InboundDownwardMessage {
+			sent_at: 1,
+			msg: b"down".to_vec(),
+		};
+	}
+
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, relay_block_num, sproof| match relay_block_num {
+			1 => {
+				sproof.dmq_mqc_head =
+					Some(MessageQueueChain::default().extend_downward(&MSG).head());
+			}
+			_ => unreachable!(),
+		})
+		.with_inherent_data(|_, relay_block_num, data| match relay_block_num {
+			1 => {
+				data.downward_messages.push(MSG.clone());
+			}
+			_ => unreachable!(),
+		})
+		.add(1, || {
+			HANDLED_DMP_MESSAGES.with(|m| {
+				let mut m = m.borrow_mut();
+				assert_eq!(&*m, &[(MSG.sent_at, MSG.msg.clone())]);
+				m.clear();
+			});
+		});
+}
+
+#[test]
+fn receive_hrmp() {
+	lazy_static::lazy_static! {
+		static ref MSG_1: InboundHrmpMessage = InboundHrmpMessage {
+			sent_at: 1,
+			data: b"1".to_vec(),
+		};
+
+		static ref MSG_2: InboundHrmpMessage = InboundHrmpMessage {
+			sent_at: 1,
+			data: b"2".to_vec(),
+		};
+
+		static ref MSG_3: InboundHrmpMessage = InboundHrmpMessage {
+			sent_at: 2,
+			data: b"3".to_vec(),
+		};
+
+		static ref MSG_4: InboundHrmpMessage = InboundHrmpMessage {
+			sent_at: 2,
+			data: b"4".to_vec(),
+		};
+	}
+
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, relay_block_num, sproof| match relay_block_num {
+			1 => {
+				// 200 - doesn't exist yet
+				// 300 - one new message
+				sproof.upsert_inbound_channel(ParaId::from(300)).mqc_head =
+					Some(MessageQueueChain::default().extend_hrmp(&MSG_1).head());
+			}
+			2 => {
+				// 200 - two new messages
+				// 300 - now present with one message.
+				sproof.upsert_inbound_channel(ParaId::from(200)).mqc_head =
+					Some(MessageQueueChain::default().extend_hrmp(&MSG_4).head());
+				sproof.upsert_inbound_channel(ParaId::from(300)).mqc_head = Some(
+					MessageQueueChain::default()
+						.extend_hrmp(&MSG_1)
+						.extend_hrmp(&MSG_2)
+						.extend_hrmp(&MSG_3)
+						.head(),
+				);
+			}
+			3 => {
+				// 200 - no new messages
+				// 300 - is gone
+				sproof.upsert_inbound_channel(ParaId::from(200)).mqc_head =
+					Some(MessageQueueChain::default().extend_hrmp(&MSG_4).head());
+			}
+			_ => unreachable!(),
+		})
+		.with_inherent_data(|_, relay_block_num, data| match relay_block_num {
+			1 => {
+				data.horizontal_messages
+					.insert(ParaId::from(300), vec![MSG_1.clone()]);
+			}
+			2 => {
+				data.horizontal_messages.insert(
+					ParaId::from(300),
+					vec![
+						// can't be sent at the block 1 actually. However, we cheat here
+						// because we want to test the case where there are multiple messages
+						// but the harness at the moment doesn't support block skipping.
+						MSG_2.clone(),
+						MSG_3.clone(),
+					],
+				);
+				data.horizontal_messages
+					.insert(ParaId::from(200), vec![MSG_4.clone()]);
+			}
+			3 => {}
+			_ => unreachable!(),
+		})
+		.add(1, || {
+			HANDLED_XCMP_MESSAGES.with(|m| {
+				let mut m = m.borrow_mut();
+				assert_eq!(&*m, &[(ParaId::from(300), 1, b"1".to_vec())]);
+				m.clear();
+			});
+		})
+		.add(2, || {
+			HANDLED_XCMP_MESSAGES.with(|m| {
+				let mut m = m.borrow_mut();
+				assert_eq!(
+					&*m,
+					&[
+						(ParaId::from(300), 1, b"2".to_vec()),
+						(ParaId::from(200), 2, b"4".to_vec()),
+						(ParaId::from(300), 2, b"3".to_vec()),
+					]
+				);
+				m.clear();
+			});
+		})
+		.add(3, || {});
+}
+
+#[test]
+fn receive_hrmp_empty_channel() {
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, relay_block_num, sproof| match relay_block_num {
+			1 => {
+				// no channels
+			}
+			2 => {
+				// one new channel
+				sproof.upsert_inbound_channel(ParaId::from(300)).mqc_head =
+					Some(MessageQueueChain::default().head());
+			}
+			_ => unreachable!(),
+		})
+		.add(1, || {})
+		.add(2, || {});
+}
+
+#[test]
+fn receive_hrmp_after_pause() {
+	lazy_static::lazy_static! {
+		static ref MSG_1: InboundHrmpMessage = InboundHrmpMessage {
+			sent_at: 1,
+			data: b"mikhailinvanovich".to_vec(),
+		};
+
+		static ref MSG_2: InboundHrmpMessage = InboundHrmpMessage {
+			sent_at: 3,
+			data: b"1000000000".to_vec(),
+		};
+	}
+
+	const ALICE: ParaId = ParaId::new(300);
+
+	BlockTests::new()
+		.with_relay_sproof_builder(|_, relay_block_num, sproof| match relay_block_num {
+			1 => {
+				sproof.upsert_inbound_channel(ALICE).mqc_head =
+					Some(MessageQueueChain::default().extend_hrmp(&MSG_1).head());
+			}
+			2 => {
+				// 300 - no new messages, mqc stayed the same.
+				sproof.upsert_inbound_channel(ALICE).mqc_head =
+					Some(MessageQueueChain::default().extend_hrmp(&MSG_1).head());
+			}
+			3 => {
+				// 300 - new message.
+				sproof.upsert_inbound_channel(ALICE).mqc_head = Some(
+					MessageQueueChain::default()
+						.extend_hrmp(&MSG_1)
+						.extend_hrmp(&MSG_2)
+						.head(),
+				);
+			}
+			_ => unreachable!(),
+		})
+		.with_inherent_data(|_, relay_block_num, data| match relay_block_num {
+			1 => {
+				data.horizontal_messages.insert(ALICE, vec![MSG_1.clone()]);
+			}
+			2 => {
+				// no new messages
+			}
+			3 => {
+				data.horizontal_messages.insert(ALICE, vec![MSG_2.clone()]);
+			}
+			_ => unreachable!(),
+		})
+		.add(1, || {
+			HANDLED_XCMP_MESSAGES.with(|m| {
+				let mut m = m.borrow_mut();
+				assert_eq!(&*m, &[(ALICE, 1, b"mikhailinvanovich".to_vec())]);
+				m.clear();
+			});
+		})
+		.add(2, || {})
+		.add(3, || {
+			HANDLED_XCMP_MESSAGES.with(|m| {
+				let mut m = m.borrow_mut();
+				assert_eq!(&*m, &[(ALICE, 3, b"1000000000".to_vec())]);
+				m.clear();
+			});
+		});
+}
@@ -25,29 +25,145 @@

 #![cfg_attr(not(feature = "std"), no_std)]

-use sp_std::{prelude::*, convert::TryFrom};
-use rand_chacha::{rand_core::{RngCore, SeedableRng}, ChaChaRng};
 use codec::{Decode, Encode};
-use sp_runtime::{RuntimeDebug, traits::Hash};
-use frame_support::{decl_error, decl_event, decl_module, decl_storage, dispatch::Weight};
-use xcm::{
-	VersionedXcm, v0::{
-		Error as XcmError, ExecuteXcm, Junction, MultiLocation, SendXcm, Outcome, Xcm,
-	},
-};
 use cumulus_primitives_core::{
-	XcmpMessageHandler, ParaId, XcmpMessageSource, ChannelStatus, MessageSendError, GetChannelInfo,
-	relay_chain::BlockNumber as RelayBlockNumber,
+	relay_chain::BlockNumber as RelayBlockNumber, ChannelStatus, GetChannelInfo, MessageSendError,
+	ParaId, XcmpMessageHandler, XcmpMessageSource,
+};
+use frame_support::weights::Weight;
+use rand_chacha::{
+	rand_core::{RngCore, SeedableRng},
+	ChaChaRng,
+};
+use sp_runtime::{traits::Hash, RuntimeDebug};
+use sp_std::{convert::TryFrom, prelude::*};
+use xcm::{
+	v0::{Error as XcmError, ExecuteXcm, Junction, MultiLocation, Outcome, SendXcm, Xcm},
+	VersionedXcm,
 };

-pub trait Config: frame_system::Config {
-	type Event: From<Event<Self>> + Into<<Self as frame_system::Config>::Event>;
+pub use pallet::*;

-	/// Something to execute an XCM message. We need this to service the XCMoXCMP queue.
-	type XcmExecutor: ExecuteXcm<Self::Call>;
+#[frame_support::pallet]
+pub mod pallet {
+	use super::*;
+	use frame_support::pallet_prelude::*;
+	use frame_system::pallet_prelude::*;

-	/// Information on the avaialble XCMP channels.
-	type ChannelInfo: GetChannelInfo;
+	#[pallet::pallet]
+	#[pallet::generate_store(pub(super) trait Store)]
+	pub struct Pallet<T>(_);
+
+	#[pallet::config]
+	pub trait Config: frame_system::Config {
+		type Event: From<Event<Self>> + IsType<<Self as frame_system::Config>::Event>;
+
+		/// Something to execute an XCM message. We need this to service the XCMoXCMP queue.
+		type XcmExecutor: ExecuteXcm<Self::Call>;
+
+		/// Information on the avaialble XCMP channels.
+		type ChannelInfo: GetChannelInfo;
+	}
+
+	impl Default for QueueConfigData {
+		fn default() -> Self {
+			Self {
+				suspend_threshold: 2,
+				drop_threshold: 5,
+				resume_threshold: 1,
+				threshold_weight: 100_000,
+				weight_restrict_decay: 2,
+			}
+		}
+	}
+
+	#[pallet::hooks]
+	impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {
+		fn on_idle(_now: T::BlockNumber, max_weight: Weight) -> Weight {
+			// on_idle processes additional messages with any remaining block weight.
+			Self::service_xcmp_queue(max_weight)
+		}
+	}
+
+	#[pallet::call]
+	impl<T: Config> Pallet<T> {}
+
+	#[pallet::event]
+	#[pallet::generate_deposit(pub(super) fn deposit_event)]
+	#[pallet::metadata(Option<T::Hash> = "Option<Hash>")]
+	pub enum Event<T: Config> {
+		/// Some XCM was executed ok.
+		Success(Option<T::Hash>),
+		/// Some XCM failed.
+		Fail(Option<T::Hash>, XcmError),
+		/// Bad XCM version used.
+		BadVersion(Option<T::Hash>),
+		/// Bad XCM format used.
+		BadFormat(Option<T::Hash>),
+		/// An upward message was sent to the relay chain.
+		UpwardMessageSent(Option<T::Hash>),
+		/// An HRMP message was sent to a sibling parachain.
+		XcmpMessageSent(Option<T::Hash>),
+	}
+
+	#[pallet::error]
+	pub enum Error<T> {
+		/// Failed to send XCM message.
+		FailedToSend,
+		/// Bad XCM origin.
+		BadXcmOrigin,
+		/// Bad XCM data.
+		BadXcm,
+	}
+
+	/// Status of the inbound XCMP channels.
+	#[pallet::storage]
+	pub(super) type InboundXcmpStatus<T: Config> = StorageValue<
+		_,
+		Vec<(
+			ParaId,
+			InboundStatus,
+			Vec<(RelayBlockNumber, XcmpMessageFormat)>,
+		)>,
+		ValueQuery,
+	>;
+
+	/// Inbound aggregate XCMP messages. It can only be one per ParaId/block.
+	#[pallet::storage]
+	pub(super) type InboundXcmpMessages<T: Config> = StorageDoubleMap<
+		_,
+		Blake2_128Concat,
+		ParaId,
+		Twox64Concat,
+		RelayBlockNumber,
+		Vec<u8>,
+		ValueQuery,
+	>;
+
+	/// The non-empty XCMP channels in order of becoming non-empty, and the index of the first
+	/// and last outbound message. If the two indices are equal, then it indicates an empty
+	/// queue and there must be a non-`Ok` `OutboundStatus`. We assume queues grow no greater
+	/// than 65535 items. Queue indices for normal messages begin at one; zero is reserved in
+	/// case of the need to send a high-priority signal message this block.
+	/// The bool is true if there is a signal message waiting to be sent.
+	#[pallet::storage]
+	pub(super) type OutboundXcmpStatus<T: Config> =
+		StorageValue<_, Vec<(ParaId, OutboundStatus, bool, u16, u16)>, ValueQuery>;
+
+	// The new way of doing it:
+	/// The messages outbound in a given XCMP channel.
+	#[pallet::storage]
+	pub(super) type OutboundXcmpMessages<T: Config> =
+		StorageDoubleMap<_, Blake2_128Concat, ParaId, Twox64Concat, u16, Vec<u8>, ValueQuery>;
+
+	/// Any signal messages waiting to be sent.
+	#[pallet::storage]
+	pub(super) type SignalMessages<T: Config> =
+		StorageMap<_, Blake2_128Concat, ParaId, Vec<u8>, ValueQuery>;
+
+	/// The configuration which controls the dynamics of the outbound queue.
+	#[pallet::storage]
+	pub(super) type QueueConfig<T: Config> = StorageValue<_, QueueConfigData, ValueQuery>;
 }

 #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Encode, Decode, RuntimeDebug)]
@@ -80,90 +196,6 @@ pub struct QueueConfigData {
 	weight_restrict_decay: Weight,
 }

-impl Default for QueueConfigData {
-	fn default() -> Self {
-		Self {
-			suspend_threshold: 2,
-			drop_threshold: 5,
-			resume_threshold: 1,
-			threshold_weight: 100_000,
-			weight_restrict_decay: 2,
-		}
-	}
-}
-
-decl_storage! {
-	trait Store for Module<T: Config> as XcmHandler {
-		/// Status of the inbound XCMP channels.
-		InboundXcmpStatus: Vec<(ParaId, InboundStatus, Vec<(RelayBlockNumber, XcmpMessageFormat)>)>;
-
-		/// Inbound aggregate XCMP messages. It can only be one per ParaId/block.
-		InboundXcmpMessages: double_map hasher(blake2_128_concat) ParaId,
-			hasher(twox_64_concat) RelayBlockNumber
-			=> Vec<u8>;
-
-		/// The non-empty XCMP channels in order of becoming non-empty, and the index of the first
-		/// and last outbound message. If the two indices are equal, then it indicates an empty
-		/// queue and there must be a non-`Ok` `OutboundStatus`. We assume queues grow no greater
-		/// than 65535 items. Queue indices for normal messages begin at one; zero is reserved in
-		/// case of the need to send a high-priority signal message this block.
-		/// The bool is true if there is a signal message waiting to be sent.
-		OutboundXcmpStatus: Vec<(ParaId, OutboundStatus, bool, u16, u16)>;
-
-		// The new way of doing it:
-		/// The messages outbound in a given XCMP channel.
-		OutboundXcmpMessages: double_map hasher(blake2_128_concat) ParaId,
-			hasher(twox_64_concat) u16 => Vec<u8>;
-
-		/// Any signal messages waiting to be sent.
-		SignalMessages: map hasher(blake2_128_concat) ParaId => Vec<u8>;
-
-		/// The configuration which controls the dynamics of the outbound queue.
-		QueueConfig: QueueConfigData;
-	}
-}
-
-decl_event! {
-	pub enum Event<T> where Hash = <T as frame_system::Config>::Hash {
-		/// Some XCM was executed ok.
-		Success(Option<Hash>),
-		/// Some XCM failed.
-		Fail(Option<Hash>, XcmError),
-		/// Bad XCM version used.
-		BadVersion(Option<Hash>),
-		/// Bad XCM format used.
-		BadFormat(Option<Hash>),
-		/// An upward message was sent to the relay chain.
-		UpwardMessageSent(Option<Hash>),
-		/// An HRMP message was sent to a sibling parachain.
-		XcmpMessageSent(Option<Hash>),
-	}
-}
-
-decl_error! {
-	pub enum Error for Module<T: Config> {
-		/// Failed to send XCM message.
-		FailedToSend,
-		/// Bad XCM origin.
-		BadXcmOrigin,
-		/// Bad XCM data.
-		BadXcm,
-	}
-}
-
-decl_module! {
-	pub struct Module<T: Config> for enum Call where origin: T::Origin {
-		type Error = Error<T>;
-
-		fn deposit_event() = default;
-
-		fn on_idle(_now: T::BlockNumber, max_weight: Weight) -> Weight {
-			// on_idle processes additional messages with any remaining block weight.
-			Self::service_xcmp_queue(max_weight)
-		}
-	}
-}
-
 #[derive(PartialEq, Eq, Copy, Clone, Encode, Decode)]
 pub enum ChannelSignal {
 	Suspend,
@@ -182,7 +214,7 @@ pub enum XcmpMessageFormat {
 	Signals,
 }

-impl<T: Config> Module<T> {
+impl<T: Config> Pallet<T> {
 	/// Place a message `fragment` on the outgoing XCMP queue for `recipient`.
 	///
 	/// Format is the type of aggregate message that the `fragment` may be safely encoded and
@@ -213,25 +245,32 @@ impl<T: Config> Module<T> {
 		// Optimization note: `max_message_size` could potentially be stored in
 		// `OutboundXcmpMessages` once known; that way it's only accessed when a new page is needed.

-		let max_message_size = T::ChannelInfo::get_channel_max(recipient)
-			.ok_or(MessageSendError::NoChannel)?;
+		let max_message_size =
+			T::ChannelInfo::get_channel_max(recipient).ok_or(MessageSendError::NoChannel)?;
 		if data.len() > max_message_size {
 			return Err(MessageSendError::TooBig);
 		}

-		let mut s = OutboundXcmpStatus::get();
-		let index = s.iter().position(|item| item.0 == recipient)
+		let mut s = <OutboundXcmpStatus<T>>::get();
+		let index = s
+			.iter()
+			.position(|item| item.0 == recipient)
 			.unwrap_or_else(|| {
 				s.push((recipient, OutboundStatus::Ok, false, 0, 0));
 				s.len() - 1
 			});
 		let have_active = s[index].4 > s[index].3;
-		let appended = have_active && OutboundXcmpMessages::mutate(recipient, s[index].4 - 1, |s| {
-			if XcmpMessageFormat::decode(&mut &s[..]) != Ok(format) { return false }
-			if s.len() + data.len() > max_message_size { return false }
-			s.extend_from_slice(&data[..]);
-			return true
-		});
+		let appended = have_active
+			&& <OutboundXcmpMessages<T>>::mutate(recipient, s[index].4 - 1, |s| {
+				if XcmpMessageFormat::decode(&mut &s[..]) != Ok(format) {
+					return false;
+				}
+				if s.len() + data.len() > max_message_size {
+					return false;
+				}
+				s.extend_from_slice(&data[..]);
+				return true;
+			});
 		if appended {
 			Ok((s[index].4 - s[index].3 - 1) as u32)
 		} else {
@@ -240,9 +279,9 @@ impl<T: Config> Module<T> {
 			s[index].4 += 1;
 			let mut new_page = format.encode();
 			new_page.extend_from_slice(&data[..]);
-			OutboundXcmpMessages::insert(recipient, page_index, new_page);
+			<OutboundXcmpMessages<T>>::insert(recipient, page_index, new_page);
 			let r = (s[index].4 - s[index].3 - 1) as u32;
-			OutboundXcmpStatus::put(s);
+			<OutboundXcmpStatus<T>>::put(s);
 			Ok(r)
 		}
 	}
@@ -250,26 +289,25 @@ impl<T: Config> Module<T> {
 	/// Sends a signal to the `dest` chain over XCMP. This is guaranteed to be dispatched on this
 	/// block.
 	fn send_signal(dest: ParaId, signal: ChannelSignal) -> Result<(), ()> {
-		let mut s = OutboundXcmpStatus::get();
+		let mut s = <OutboundXcmpStatus<T>>::get();
 		if let Some(index) = s.iter().position(|item| item.0 == dest) {
 			s[index].2 = true;
 		} else {
 			s.push((dest, OutboundStatus::Ok, true, 0, 0));
 		}
-		SignalMessages::mutate(dest, |page| if page.is_empty() {
-			*page = (XcmpMessageFormat::Signals, signal).encode();
-		} else {
-			signal.using_encoded(|s| page.extend_from_slice(s));
+		<SignalMessages<T>>::mutate(dest, |page| {
+			if page.is_empty() {
+				*page = (XcmpMessageFormat::Signals, signal).encode();
+			} else {
+				signal.using_encoded(|s| page.extend_from_slice(s));
+			}
 		});
-		OutboundXcmpStatus::put(s);
+		<OutboundXcmpStatus<T>>::put(s);

 		Ok(())
 	}

-	pub fn send_blob_message(
-		recipient: ParaId,
-		blob: Vec<u8>,
-	) -> Result<u32, MessageSendError> {
+	pub fn send_blob_message(recipient: ParaId, blob: Vec<u8>) -> Result<u32, MessageSendError> {
 		Self::send_fragment(recipient, XcmpMessageFormat::ConcatenatedEncodedBlob, blob)
 	}

@@ -284,8 +322,10 @@ impl<T: Config> Module<T> {
 		// Create a shuffled order for use to iterate through.
 		// Not a great random seed, but good enough for our purposes.
 		let seed = frame_system::Pallet::<T>::parent_hash();
-		let seed = <[u8; 32]>::decode(&mut sp_runtime::traits::TrailingZeroInput::new(seed.as_ref()))
-			.expect("input is padded with zeroes; qed");
+		let seed = <[u8; 32]>::decode(&mut sp_runtime::traits::TrailingZeroInput::new(
+			seed.as_ref(),
+		))
+		.expect("input is padded with zeroes; qed");
 		let mut rng = ChaChaRng::from_seed(seed);
 		let mut shuffled = (0..len).collect::<Vec<_>>();
 		for i in 0..len {
@@ -297,7 +337,12 @@ impl<T: Config> Module<T> {
 		shuffled
 	}

-	fn handle_blob_message(_sender: ParaId, _sent_at: RelayBlockNumber, _blob: Vec<u8>, _weight_limit: Weight) -> Result<Weight, bool> {
+	fn handle_blob_message(
+		_sender: ParaId,
+		_sent_at: RelayBlockNumber,
+		_blob: Vec<u8>,
+		_weight_limit: Weight,
+	) -> Result<Weight, bool> {
 		debug_assert!(false, "Blob messages not handled.");
 		Err(false)
 	}
@@ -312,23 +357,19 @@ impl<T: Config> Module<T> {
 		log::debug!("Processing XCMP-XCM: {:?}", &hash);
 		let (result, event) = match Xcm::<T::Call>::try_from(xcm) {
 			Ok(xcm) => {
-				let location = (
-					Junction::Parent,
-					Junction::Parachain(sender.into()),
-				);
-				match T::XcmExecutor::execute_xcm(
-					location.into(),
-					xcm,
-					max_weight,
-				) {
-					Outcome::Error(e) => (Err(e.clone()), RawEvent::Fail(Some(hash), e)),
-					Outcome::Complete(w) => (Ok(w), RawEvent::Success(Some(hash))),
+				let location = (Junction::Parent, Junction::Parachain(sender.into()));
+				match T::XcmExecutor::execute_xcm(location.into(), xcm, max_weight) {
+					Outcome::Error(e) => (Err(e.clone()), Event::Fail(Some(hash), e)),
+					Outcome::Complete(w) => (Ok(w), Event::Success(Some(hash))),
 					// As far as the caller is concerned, this was dispatched without error, so
 					// we just report the weight used.
-					Outcome::Incomplete(w, e) => (Ok(w), RawEvent::Fail(Some(hash), e)),
+					Outcome::Incomplete(w, e) => (Ok(w), Event::Fail(Some(hash), e)),
 				}
 			}
-			Err(()) => (Err(XcmError::UnhandledXcmVersion), RawEvent::BadVersion(Some(hash))),
+			Err(()) => (
+				Err(XcmError::UnhandledXcmVersion),
+				Event::BadVersion(Some(hash)),
+			),
 		};
 		Self::deposit_event(event);
 		result
@@ -339,7 +380,7 @@ impl<T: Config> Module<T> {
 		(sent_at, format): (RelayBlockNumber, XcmpMessageFormat),
 		max_weight: Weight,
 	) -> (Weight, bool) {
-		let data = InboundXcmpMessages::get(sender, sent_at);
+		let data = <InboundXcmpMessages<T>>::get(sender, sent_at);
 		let mut last_remaining_fragments;
 		let mut remaining_fragments = &data[..];
 		let mut weight_used = 0;
@@ -397,9 +438,9 @@ impl<T: Config> Module<T> {
 		}
 		let is_empty = remaining_fragments.is_empty();
 		if is_empty {
-			InboundXcmpMessages::remove(sender, sent_at);
+			<InboundXcmpMessages<T>>::remove(sender, sent_at);
 		} else {
-			InboundXcmpMessages::insert(sender, sent_at, remaining_fragments);
+			<InboundXcmpMessages<T>>::insert(sender, sent_at, remaining_fragments);
 		}
 		(weight_used, is_empty)
 	}
@@ -432,9 +473,9 @@ impl<T: Config> Module<T> {
 	/// for the second &c. though empirical and or practical factors may give rise to adjusting it
 	/// further.
 	fn service_xcmp_queue(max_weight: Weight) -> Weight {
-		let mut status = InboundXcmpStatus::get(); // <- sorted.
+		let mut status = <InboundXcmpStatus<T>>::get(); // <- sorted.
 		if status.len() == 0 {
-			return 0
+			return 0;
 		}

 		let QueueConfigData {
@@ -442,7 +483,7 @@ impl<T: Config> Module<T> {
 			threshold_weight,
 			weight_restrict_decay,
 			..
-		} = QueueConfig::get();
+		} = <QueueConfig<T>>::get();

 		let mut shuffled = Self::create_shuffle(status.len());
 		let mut weight_used = 0;
@@ -457,7 +498,9 @@ impl<T: Config> Module<T> {
 		// send more, heavier messages.

 		let mut shuffle_index = 0;
-		while shuffle_index < shuffled.len() && max_weight.saturating_sub(weight_used) >= threshold_weight {
+		while shuffle_index < shuffled.len()
+			&& max_weight.saturating_sub(weight_used) >= threshold_weight
+		{
 			let index = shuffled[shuffle_index];
 			let sender = status[index].0;

@@ -466,7 +509,8 @@ impl<T: Config> Module<T> {
 				// first round. For the second round we unlock all weight. If we come close enough
 				// on the first round to unlocking everything, then we do so.
 				if shuffle_index < status.len() {
-					weight_available += (max_weight - weight_available) / (weight_restrict_decay + 1);
+					weight_available +=
+						(max_weight - weight_available) / (weight_restrict_decay + 1);
 					if weight_available + threshold_weight > max_weight {
 						weight_available = max_weight;
 					}
@@ -476,16 +520,16 @@ impl<T: Config> Module<T> {
 			}

 			let weight_processed = if status[index].2.is_empty() {
-				debug_assert!(false, "channel exists in status; there must be messages; qed");
+				debug_assert!(
+					false,
+					"channel exists in status; there must be messages; qed"
+				);
 				0
 			} else {
 				// Process up to one block's worth for now.
 				let weight_remaining = weight_available.saturating_sub(weight_used);
-				let (weight_processed, is_empty) = Self::process_xcmp_message(
-					sender,
-					status[index].2[0],
-					weight_remaining,
-				);
+				let (weight_processed, is_empty) =
+					Self::process_xcmp_message(sender, status[index].2[0], weight_remaining);
 				if is_empty {
 					status[index].2.remove(0);
 				}
@@ -493,20 +537,26 @@ impl<T: Config> Module<T> {
 			};
 			weight_used += weight_processed;

-			if status[index].2.len() as u32 <= resume_threshold && status[index].1 == InboundStatus::Suspended {
+			if status[index].2.len() as u32 <= resume_threshold
+				&& status[index].1 == InboundStatus::Suspended
+			{
 				// Resume
 				let r = Self::send_signal(sender, ChannelSignal::Resume);
-				debug_assert!(r.is_ok(), "WARNING: Failed sending resume into suspended channel");
+				debug_assert!(
+					r.is_ok(),
+					"WARNING: Failed sending resume into suspended channel"
+				);
 				status[index].1 = InboundStatus::Ok;
 			}

 			// If there are more and we're making progress, we process them after we've given the
 			// other channels a look in. If we've still not unlocked all weight, then we set them
 			// up for processing a second time anyway.
-			if !status[index].2.is_empty() && weight_processed > 0 || weight_available != max_weight {
+			if !status[index].2.is_empty() && weight_processed > 0 || weight_available != max_weight
+			{
 				if shuffle_index + 1 == shuffled.len() {
 					// Only this queue left. Just run around this loop once more.
-					continue
+					continue;
 				}
 				shuffled.push(index);
 			}
@@ -516,12 +566,12 @@ impl<T: Config> Module<T> {
 		// Only retain the senders that have non-empty queues.
 		status.retain(|item| !item.2.is_empty());

-		InboundXcmpStatus::put(status);
+		<InboundXcmpStatus<T>>::put(status);
 		weight_used
 	}

 	fn suspend_channel(target: ParaId) {
-		OutboundXcmpStatus::mutate(|s| {
+		<OutboundXcmpStatus<T>>::mutate(|s| {
 			if let Some(index) = s.iter().position(|item| item.0 == target) {
 				let ok = s[index].1 == OutboundStatus::Ok;
 				debug_assert!(ok, "WARNING: Attempt to suspend channel that was not Ok.");
@@ -533,41 +583,53 @@ impl<T: Config> Module<T> {
 	}

 	fn resume_channel(target: ParaId) {
-		OutboundXcmpStatus::mutate(|s| {
+		<OutboundXcmpStatus<T>>::mutate(|s| {
 			if let Some(index) = s.iter().position(|item| item.0 == target) {
 				let suspended = s[index].1 == OutboundStatus::Suspended;
-				debug_assert!(suspended, "WARNING: Attempt to resume channel that was not suspended.");
+				debug_assert!(
+					suspended,
+					"WARNING: Attempt to resume channel that was not suspended."
+				);
 				if s[index].3 == s[index].4 {
 					s.remove(index);
 				} else {
 					s[index].1 = OutboundStatus::Ok;
 				}
 			} else {
-				debug_assert!(false, "WARNING: Attempt to resume channel that was not suspended.");
+				debug_assert!(
+					false,
+					"WARNING: Attempt to resume channel that was not suspended."
+				);
 			}
 		});
 	}
 }

-impl<T: Config> XcmpMessageHandler for Module<T> {
-	fn handle_xcmp_messages<'a, I: Iterator<Item=(ParaId, RelayBlockNumber, &'a [u8])>>(
+impl<T: Config> XcmpMessageHandler for Pallet<T> {
+	fn handle_xcmp_messages<'a, I: Iterator<Item = (ParaId, RelayBlockNumber, &'a [u8])>>(
 		iter: I,
 		max_weight: Weight,
 	) -> Weight {
-		let mut status = InboundXcmpStatus::get();
+		let mut status = <InboundXcmpStatus<T>>::get();

-		let QueueConfigData { suspend_threshold, drop_threshold, .. } = QueueConfig::get();
+		let QueueConfigData {
+			suspend_threshold,
+			drop_threshold,
+			..
+		} = <QueueConfig<T>>::get();

 		for (sender, sent_at, data) in iter {
-
 			// Figure out the message format.
 			let mut data_ref = data;
 			let format = match XcmpMessageFormat::decode(&mut data_ref) {
 				Ok(f) => f,
 				Err(_) => {
-					debug_assert!(false, "Unknown XCMP message format. Silently dropping message");
-					continue
-				},
+					debug_assert!(
+						false,
+						"Unknown XCMP message format. Silently dropping message"
+					);
+					continue;
+				}
 			};
 			if format == XcmpMessageFormat::Signals {
 				while !data_ref.is_empty() {
@@ -587,34 +649,39 @@ impl<T: Config> XcmpMessageHandler for Module<T> {
 							status[i].1 = InboundStatus::Suspended;
 							let r = Self::send_signal(sender, ChannelSignal::Suspend);
 							if r.is_err() {
-								log::warn!("Attempt to suspend channel failed. Messages may be dropped.");
+								log::warn!(
+									"Attempt to suspend channel failed. Messages may be dropped."
+								);
 							}
 						}
 						if (count as u32) < drop_threshold {
 							status[i].2.push((sent_at, format));
 						} else {
-							debug_assert!(false, "XCMP channel queue full. Silently dropping message");
+							debug_assert!(
+								false,
+								"XCMP channel queue full. Silently dropping message"
+							);
 						}
-					},
+					}
 					Err(_) => status.push((sender, InboundStatus::Ok, vec![(sent_at, format)])),
 				}
 				// Queue the payload for later execution.
-				InboundXcmpMessages::insert(sender, sent_at, data_ref);
+				<InboundXcmpMessages<T>>::insert(sender, sent_at, data_ref);
 			}

 			// Optimization note; it would make sense to execute messages immediately if
 			// `status.is_empty()` here.
 		}
 		status.sort();
-		InboundXcmpStatus::put(status);
+		<InboundXcmpStatus<T>>::put(status);

 		Self::service_xcmp_queue(max_weight)
 	}
 }

-impl<T: Config> XcmpMessageSource for Module<T> {
+impl<T: Config> XcmpMessageSource for Pallet<T> {
 	fn take_outbound_messages(maximum_channels: usize) -> Vec<(ParaId, Vec<u8>)> {
-		let mut statuses = OutboundXcmpStatus::get();
+		let mut statuses = <OutboundXcmpStatus<T>>::get();
 		let old_statuses_len = statuses.len();
 		let max_message_count = statuses.len().min(maximum_channels);
 		let mut result = Vec::with_capacity(max_message_count);
@@ -628,42 +695,42 @@ impl<T: Config> XcmpMessageSource for Module<T> {
 				break;
 			}
 			if outbound_status == OutboundStatus::Suspended {
-				continue
+				continue;
 			}
 			let (max_size_now, max_size_ever) = match T::ChannelInfo::get_channel_status(para_id) {
 				ChannelStatus::Closed => {
 					// This means that there is no such channel anymore. Nothing to be done but
 					// swallow the messages and discard the status.
 					for i in begin..end {
-						OutboundXcmpMessages::remove(para_id, i);
+						<OutboundXcmpMessages<T>>::remove(para_id, i);
 					}
 					if signalling {
-						SignalMessages::remove(para_id);
+						<SignalMessages<T>>::remove(para_id);
 					}
 					*status = (para_id, OutboundStatus::Ok, false, 0, 0);
-					continue
+					continue;
 				}
 				ChannelStatus::Full => continue,
 				ChannelStatus::Ready(n, e) => (n, e),
 			};

 			let page = if signalling {
-				let page = SignalMessages::get(para_id);
+				let page = <SignalMessages<T>>::get(para_id);
 				if page.len() < max_size_now {
-					SignalMessages::remove(para_id);
+					<SignalMessages<T>>::remove(para_id);
 					signalling = false;
 					page
 				} else {
-					continue
+					continue;
 				}
 			} else if end > begin {
-				let page = OutboundXcmpMessages::get(para_id, begin);
+				let page = <OutboundXcmpMessages<T>>::get(para_id, begin);
 				if page.len() < max_size_now {
-					OutboundXcmpMessages::remove(para_id, begin);
+					<OutboundXcmpMessages<T>>::remove(para_id, begin);
 					begin += 1;
 					page
 				} else {
-					continue
+					continue;
 				}
 			} else {
 				continue;
@@ -705,23 +772,27 @@ impl<T: Config> XcmpMessageSource for Module<T> {
 		// be no less than the pruned channels.
 		statuses.rotate_left(result.len() - pruned);

-		OutboundXcmpStatus::put(statuses);
+		<OutboundXcmpStatus<T>>::put(statuses);

 		result
 	}
 }

 /// Xcm sender for sending to a sibling parachain.
-impl<T: Config> SendXcm for Module<T> {
+impl<T: Config> SendXcm for Pallet<T> {
 	fn send_xcm(dest: MultiLocation, msg: Xcm<()>) -> Result<(), XcmError> {
 		match &dest {
 			// An HRMP message for a sibling parachain.
 			MultiLocation::X2(Junction::Parent, Junction::Parachain(id)) => {
 				let msg = VersionedXcm::<()>::from(msg);
 				let hash = T::Hashing::hash_of(&msg);
-				Self::send_fragment((*id).into(), XcmpMessageFormat::ConcatenatedVersionedXcm, msg)
-					.map_err(|e| XcmError::SendFailed(<&'static str>::from(e)))?;
-				Self::deposit_event(RawEvent::XcmpMessageSent(Some(hash)));
+				Self::send_fragment(
+					(*id).into(),
+					XcmpMessageFormat::ConcatenatedVersionedXcm,
+					msg,
+				)
+				.map_err(|e| XcmError::SendFailed(<&'static str>::from(e)))?;
+				Self::deposit_event(Event::XcmpMessageSent(Some(hash)));
 				Ok(())
 			}
 			// Anything else is unhandled. This includes a message this is meant for us.
@@ -18,25 +18,58 @@

 #![cfg_attr(not(feature = "std"), no_std)]

-use frame_support::{decl_module, decl_storage, traits::Get};
+pub use pallet::*;

-use cumulus_primitives_core::ParaId;
+#[frame_support::pallet]
+pub mod pallet {
+	use frame_support::pallet_prelude::*;
+	use frame_system::pallet_prelude::*;
+	use cumulus_primitives_core::ParaId;

-/// Configuration trait of this pallet.
-pub trait Config: frame_system::Config {}
+	#[pallet::pallet]
+	#[pallet::generate_store(pub(super) trait Store)]
+	pub struct Pallet<T>(_);

-impl<T: Config> Get<ParaId> for Module<T> {
-	fn get() -> ParaId {
-		Self::parachain_id()
+	#[pallet::config]
+	pub trait Config: frame_system::Config {}
+
+	#[pallet::hooks]
+	impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {}
+
+	#[pallet::call]
+	impl<T: Config> Pallet<T> {}
+
+	#[pallet::genesis_config]
+	pub struct GenesisConfig {
+		pub parachain_id: ParaId,
+	}
+
+	#[cfg(feature = "std")]
+	impl Default for GenesisConfig {
+		fn default() -> Self {
+			Self {
+				parachain_id: 100.into()
+			}
+		}
+	}
+
+	#[pallet::genesis_build]
+	impl<T: Config> GenesisBuild<T> for GenesisConfig {
+		fn build(&self) {
+			<ParachainId<T>>::put(&self.parachain_id);
+		}
+	}
+
+	#[pallet::type_value]
+	pub(super) fn DefaultForParachainId() -> ParaId { 100.into() }
+
+	#[pallet::storage]
+	#[pallet::getter(fn parachain_id)]
+	pub(super) type ParachainId<T: Config> = StorageValue<_, ParaId, ValueQuery, DefaultForParachainId>;
+
+	impl<T: Config> Get<ParaId> for Pallet<T> {
+		fn get() -> ParaId {
+			Self::parachain_id()
+		}
 	}
 }
-
-decl_storage! {
-	trait Store for Module<T: Config> as ParachainInfo {
-		ParachainId get(fn parachain_id) config(): ParaId = 100.into();
-	}
-}
-
-decl_module! {
-	pub struct Module<T: Config> for enum Call where origin: T::Origin {}
-}
@@ -238,7 +238,7 @@ parameter_types! {
 impl cumulus_pallet_parachain_system::Config for Runtime {
 	type Event = Event;
 	type OnValidationData = ();
-	type SelfParaId = parachain_info::Module<Runtime>;
+	type SelfParaId = parachain_info::Pallet<Runtime>;
 	type OutboundXcmpMessageSource = XcmpQueue;
 	type DmpMessageHandler = DmpQueue;
 	type ReservedDmpWeight = ReservedDmpWeight;
@@ -161,7 +161,7 @@ parameter_types! {
 impl cumulus_pallet_parachain_system::Config for Runtime {
 	type Event = Event;
 	type OnValidationData = ();
-	type SelfParaId = parachain_info::Module<Runtime>;
+	type SelfParaId = parachain_info::Pallet<Runtime>;
 	type OutboundXcmpMessageSource = ();
 	type DmpMessageHandler = cumulus_pallet_xcm::UnlimitedDmpExecution<Runtime>;
 	type ReservedDmpWeight = ReservedDmpWeight;