More work

message-broker/Cargo.toml

@@ -18,6 +18,7 @@ codec = { package = "parity-scale-codec", version = "1.3.0", features = [ "deriv
 
 # Cumulus dependencies
 cumulus-primitives = { path = "../primitives", default-features = false }
+cumulus-upward-message = { path = "../upward-message", default-features = false }
 
 [features]
 default = [ "std" ]
@@ -30,4 +31,5 @@ std = [
 	"sp-runtime/std",
 	"codec/std",
 	"cumulus-primitives/std",
+	"cumulus-upward-message/std",
 ]

message-broker/src/lib.rs

@@ -21,12 +21,15 @@
 
 #![cfg_attr(not(feature = "std"), no_std)]
 
-use codec::Encode;
+use codec::{Encode, Decode};
 use cumulus_primitives::{
 	inherents::{DownwardMessagesType, DOWNWARD_MESSAGES_IDENTIFIER},
-	well_known_keys, DownwardMessage, DownwardMessageHandler, GenericUpwardMessage,
-	UpwardMessageOrigin, UpwardMessageSender, xcmp::{XCMPMessageHandler, XCMPMessageSender}
+	well_known_keys,
+	xcmp::{RawXCMPMessage, XCMPMessageHandler, XCMPMessageSender},
+	DownwardMessage, DownwardMessageHandler, GenericUpwardMessage, ParaId, UpwardMessageOrigin,
+	UpwardMessageSender,
 };
+use cumulus_upward_message::XCMPMessage;
 use frame_support::{
 	decl_event, decl_module, storage,
 	traits::Get,
@@ -46,13 +49,16 @@ pub trait Trait: frame_system::Trait {
 	type DownwardMessageHandlers: DownwardMessageHandler;
 
 	/// The upward message type used by the Parachain runtime.
-	type UpwardMessage: codec::Codec;
+	type UpwardMessage: codec::Codec + XCMPMessage;
 
 	/// The XCMP message handlers that will be informed when a XCMP message is received.
-	type XCMPMessageHandlers: XCMPMessageHandler;
+	type XCMPMessageHandlers: XCMPMessageHandler<Self::XCMPMessage>;
 
 	/// The XCMP message type used by the Parachain runtime.
 	type XCMPMessage: codec::Codec;
+
+	/// The Id of the parachain.
+	type ParachainId: Get<ParaId>;
 }
 
 decl_event! {
@@ -77,7 +83,16 @@ decl_module! {
 			// weight used by the handlers.
 			let max_messages = 10;
 			messages.iter().take(max_messages).for_each(|msg| {
-				T::DownwardMessageHandlers::handle_downward_message(msg);
+				match msg {
+					DownwardMessage::XCMPMessage(msg) => {
+						if let Ok(msg) = RawXCMPMessage::decode(&mut &msg[..]) {
+							if let Ok(xcmp_msg) = T::XCMPMessage::decode(&mut &msg.data[..]) {
+								T::XCMPMessageHandlers::handle_xcmp_message(msg.from, &xcmp_msg);
+							}
+						}
+					},
+					msg => T::DownwardMessageHandlers::handle_downward_message(msg),
+				}
 			});
 
 			let processed = sp_std::cmp::min(messages.len(), max_messages) as u32;
@@ -110,8 +125,16 @@ impl<T: Trait> UpwardMessageSender<T::UpwardMessage> for Module<T> {
 }
 
 impl<T: Trait> XCMPMessageSender<T::XCMPMessage> for Module<T> {
-	fn send_xcmp_message(msg: &Message) -> Result<(), ()> {
-
+	fn send_xcmp_message(dest: ParaId, msg: &T::XCMPMessage) -> Result<(), ()> {
+		let message = RawXCMPMessage {
+			from: T::ParachainId::get(),
+			data: msg.encode(),
+		};
+
+		Self::send_upward_message(
+			&T::UpwardMessage::send_message(dest, message.encode()),
+			UpwardMessageOrigin::Signed,
+		)
 	}
 }
 

primitives/src/lib.rs

@@ -26,6 +26,7 @@ pub use polkadot_core_primitives::DownwardMessage;
 /// Besides the `data` it also holds the `origin` of the message.
 pub use polkadot_parachain::primitives::UpwardMessage as GenericUpwardMessage;
 pub use polkadot_parachain::primitives::ParachainDispatchOrigin as UpwardMessageOrigin;
+pub use polkadot_parachain::primitives::Id as ParaId;
 
 pub mod validation_function_params;
 pub mod xcmp;

primitives/src/xcmp.rs

@@ -17,25 +17,26 @@
 //! XMCP related primitives
 
 use polkadot_primitives::parachain::Id as ParaId;
+use sp_std::vec::Vec;
 
 /// A raw XCMP message that is being send between two Parachain's.
+#[derive(codec::Encode, codec::Decode)]
 pub struct RawXCMPMessage {
 	/// Parachain sending the message.
 	pub from: ParaId,
-	/// Parachain receiving the message.
-	pub to: ParaId,
 	/// SCALE encoded message.
 	pub data: Vec<u8>,
 }
 
 /// Something that can handle XCMP messages.
+#[impl_trait_for_tuples::impl_for_tuples(30)]
 pub trait XCMPMessageHandler<Message: codec::Decode> {
 	/// Handle a XCMP message.
-	fn handle_xcmp_message(msg: &Message);
+	fn handle_xcmp_message(src: ParaId, msg: &Message);
 }
 
 /// Something that can send XCMP messages.
 pub trait XCMPMessageSender<Message: codec::Encode> {
-	/// Send a XCMP message.
-	fn send_xcmp_message(msg: &Message) -> Result<(), ()>;
+	/// Send a XCMP message to the given parachain.
+	fn send_xcmp_message(dest: ParaId, msg: &Message) -> Result<(), ()>;
 }

test/parachain/runtime/src/lib.rs

@@ -124,6 +124,11 @@ pub const DAYS: BlockNumber = HOURS * 24;
 // 1 in 4 blocks (on average, not counting collisions) will be primary babe blocks.
 pub const PRIMARY_PROBABILITY: (u64, u64) = (1, 4);
 
+#[derive(codec::Encode, codec::Decode)]
+pub enum XCMPMessage {
+
+}
+
 /// The version infromation used to identify this runtime when compiled natively.
 #[cfg(feature = "std")]
 pub fn native_version() -> NativeVersion {
@@ -233,10 +238,17 @@ impl cumulus_parachain_upgrade::Trait for Runtime {
 	type OnValidationFunctionParams = ();
 }
 
+parameter_types! {
+	pub storage ParachainId: cumulus_primitives::ParaId = 100.into();
+}
+
 impl cumulus_message_broker::Trait for Runtime {
 	type Event = Event;
 	type DownwardMessageHandlers = TokenDealer;
 	type UpwardMessage = cumulus_upward_message::WestendUpwardMessage;
+	type ParachainId = ParachainId;
+	type XCMPMessage = XCMPMessage;
+	type XCMPMessageHandlers = ();
 }
 
 impl message_example::Trait for Runtime {

upward-message/Cargo.toml

@@ -5,8 +5,12 @@ authors = ["Parity Technologies <[email protected]>"]
 edition = "2018"
 
 [dependencies]
+# Substrate dependencies
+sp-std = { git = "https://github.com/paritytech/substrate", branch = "bkchr-cumulus-branch", default-features = false }
+
 # Polkadot deps
 polkadot-core-primitives = { git = "https://github.com/paritytech/polkadot", branch = "bkchr-cumulus-branch", default-features = false }
+polkadot-parachain = { git = "https://github.com/paritytech/polkadot", branch = "bkchr-cumulus-branch", default-features = false }
 
 # All these should be optional dependenices, but given the perfect Cargo, it is not possible.
 polkadot-runtime = { git = "https://github.com/paritytech/polkadot", branch = "bkchr-cumulus-branch", default-features = false }
@@ -16,10 +20,12 @@ westend-runtime = { git = "https://github.com/paritytech/polkadot", branch = "bk
 [features]
 default = [ "std" ]
 std = [
+	"sp-std/std",
 	"polkadot-runtime/std",
 	"kusama-runtime/std",
 	"westend-runtime/std",
 	"polkadot-core-primitives/std",
+	"polkadot-parachain/std",
 ]
 # Should be enabled by when compiling the runtime for WASM.
 #

upward-message/src/kusama.rs

@@ -18,7 +18,8 @@
 
 use crate::*;
 use polkadot_core_primitives::{Balance, AccountId};
-use kusama_runtime::BalancesCall;
+use kusama_runtime::{BalancesCall, ParachainsCall};
+use sp_std::vec::Vec;
 
 /// The Kusama upward message.
 pub type UpwardMessage = kusama_runtime::Call;
@@ -28,3 +29,9 @@ impl BalancesMessage<AccountId, Balance> for UpwardMessage {
 		BalancesCall::transfer(dest, amount).into()
 	}
 }
+
+impl XCMPMessage for UpwardMessage {
+	fn send_message(dest: ParaId, msg: Vec<u8>) -> Self {
+		ParachainsCall::send_xcmp_message(dest, msg).into()
+	}
+}

upward-message/src/lib.rs

@@ -22,6 +22,9 @@
 
 #![cfg_attr(not(feature = "std"), no_std)]
 
+use polkadot_parachain::primitives::Id as ParaId;
+use sp_std::vec::Vec;
+
 mod polkadot;
 mod kusama;
 mod westend;
@@ -36,3 +39,9 @@ pub trait BalancesMessage<AccountId, Balance>: Sized {
 	/// `dest` account.
 	fn transfer(dest: AccountId, amount: Balance) -> Self;
 }
+
+/// A `XCMP` related upward message.
+pub trait XCMPMessage: Sized {
+	/// Send the given XCMP message to given parachain.
+	fn send_message(dest: ParaId, msg: Vec<u8>) -> Self;
+}

upward-message/src/polkadot.rs

@@ -18,7 +18,8 @@
 
 use crate::*;
 use polkadot_core_primitives::{Balance, AccountId};
-use polkadot_runtime::BalancesCall;
+use polkadot_runtime::{BalancesCall, ParachainsCall};
+use sp_std::vec::Vec;
 
 /// The Polkadot upward message.
 pub type UpwardMessage = polkadot_runtime::Call;
@@ -28,3 +29,9 @@ impl BalancesMessage<AccountId, Balance> for UpwardMessage {
 		BalancesCall::transfer(dest, amount).into()
 	}
 }
+
+impl XCMPMessage for UpwardMessage {
+	fn send_message(dest: ParaId, msg: Vec<u8>) -> Self {
+		ParachainsCall::send_xcmp_message(dest, msg).into()
+	}
+}

upward-message/src/westend.rs

@@ -18,7 +18,8 @@
 
 use crate::*;
 use polkadot_core_primitives::{Balance, AccountId};
-use westend_runtime::BalancesCall;
+use westend_runtime::{BalancesCall, ParachainsCall};
+use sp_std::vec::Vec;
 
 /// The Westend upward message.
 pub type UpwardMessage = westend_runtime::Call;
@@ -28,3 +29,9 @@ impl BalancesMessage<AccountId, Balance> for UpwardMessage {
 		BalancesCall::transfer(dest, amount).into()
 	}
 }
+
+impl XCMPMessage for UpwardMessage {
+	fn send_message(dest: ParaId, msg: Vec<u8>) -> Self {
+		ParachainsCall::send_xcmp_message(dest, msg).into()
+	}
+}