Removes Snowbridge parachain directory (#3186)

Removes the `bridges/snowbridge/parachain` directory and moves everything up to under `snowbridge` directly. We are cleaning up our local dev env after merging our crates into the polkadot-sdk. --------- Co-authored-by: claravanstaden <Cats 4 life!>
2026-07-06 12:37:23 +00:00 · 2024-02-02 19:08:36 +02:00
parent 700d5f85b7
commit 2ab3f03f0b
122 changed files with 199 additions and 529 deletions
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: 2023 Snowfork <hello@snowfork.com>
+//! # Runtime Common
+//!
+//! Common traits and types shared by runtimes.
+#![cfg_attr(not(feature = "std"), no_std)]
+
+#[cfg(test)]
+mod tests;
+
+use codec::FullCodec;
+use core::marker::PhantomData;
+use frame_support::traits::Get;
+use snowbridge_core::outbound::SendMessageFeeProvider;
+use sp_arithmetic::traits::{BaseArithmetic, Unsigned};
+use sp_std::fmt::Debug;
+use xcm::prelude::*;
+use xcm_builder::HandleFee;
+use xcm_executor::traits::{FeeReason, TransactAsset};
+
+pub const LOG_TARGET: &str = "xcm::export-fee-to-sibling";
+
+/// A `HandleFee` implementation that takes fees from `ExportMessage` XCM instructions
+/// to Snowbridge and splits off the remote fee and deposits it to the origin
+/// parachain sovereign account. The local fee is then returned back to be handled by
+/// the next fee handler in the chain. Most likely the treasury account.
+pub struct XcmExportFeeToSibling<
+	Balance,
+	AccountId,
+	FeeAssetLocation,
+	EthereumNetwork,
+	AssetTransactor,
+	FeeProvider,
+>(
+	PhantomData<(
+		Balance,
+		AccountId,
+		FeeAssetLocation,
+		EthereumNetwork,
+		AssetTransactor,
+		FeeProvider,
+	)>,
+);
+
+impl<Balance, AccountId, FeeAssetLocation, EthereumNetwork, AssetTransactor, FeeProvider> HandleFee
+	for XcmExportFeeToSibling<
+		Balance,
+		AccountId,
+		FeeAssetLocation,
+		EthereumNetwork,
+		AssetTransactor,
+		FeeProvider,
+	> where
+	Balance: BaseArithmetic + Unsigned + Copy + From<u128> + Into<u128> + Debug,
+	AccountId: Clone + FullCodec,
+	FeeAssetLocation: Get<Location>,
+	EthereumNetwork: Get<NetworkId>,
+	AssetTransactor: TransactAsset,
+	FeeProvider: SendMessageFeeProvider<Balance = Balance>,
+{
+	fn handle_fee(fees: Assets, context: Option<&XcmContext>, reason: FeeReason) -> Assets {
+		let token_location = FeeAssetLocation::get();
+
+		// Check the reason to see if this export is for snowbridge.
+		if !matches!(
+			reason,
+			FeeReason::Export { network: bridged_network, ref destination }
+				if bridged_network == EthereumNetwork::get() && destination == &Here
+		) {
+			return fees
+		}
+
+		// Get the parachain sovereign from the `context`.
+		let maybe_para_id: Option<u32> =
+			if let Some(XcmContext { origin: Some(Location { parents: 1, interior }), .. }) =
+				context
+			{
+				if let Some(Parachain(sibling_para_id)) = interior.first() {
+					Some(*sibling_para_id)
+				} else {
+					None
+				}
+			} else {
+				None
+			};
+		if maybe_para_id.is_none() {
+			log::error!(
+				target: LOG_TARGET,
+				"invalid location in context {:?}",
+				context,
+			);
+			return fees
+		}
+		let para_id = maybe_para_id.unwrap();
+
+		// Get the total fee offered by export message.
+		let maybe_total_supplied_fee: Option<(usize, Balance)> = fees
+			.inner()
+			.iter()
+			.enumerate()
+			.filter_map(|(index, asset)| {
+				if let Asset { id: location, fun: Fungible(amount) } = asset {
+					if location.0 == token_location {
+						return Some((index, (*amount).into()))
+					}
+				}
+				None
+			})
+			.next();
+		if maybe_total_supplied_fee.is_none() {
+			log::error!(
+				target: LOG_TARGET,
+				"could not find fee asset item in fees: {:?}",
+				fees,
+			);
+			return fees
+		}
+		let (fee_index, total_fee) = maybe_total_supplied_fee.unwrap();
+		let local_fee = FeeProvider::local_fee();
+		let remote_fee = total_fee.saturating_sub(local_fee);
+		if local_fee == Balance::zero() || remote_fee == Balance::zero() {
+			log::error!(
+				target: LOG_TARGET,
+				"calculated refund incorrect with local_fee: {:?} and remote_fee: {:?}",
+				local_fee,
+				remote_fee,
+			);
+			return fees
+		}
+		// Refund remote component of fee to physical origin
+		let result = AssetTransactor::deposit_asset(
+			&Asset { id: AssetId(token_location.clone()), fun: Fungible(remote_fee.into()) },
+			&Location::new(1, [Parachain(para_id)]),
+			context,
+		);
+		if result.is_err() {
+			log::error!(
+				target: LOG_TARGET,
+				"transact fee asset failed: {:?}",
+				result.unwrap_err()
+			);
+			return fees
+		}
+
+		// Return remaining fee to the next fee handler in the chain.
+		let mut modified_fees = fees.inner().clone();
+		modified_fees.remove(fee_index);
+		modified_fees.push(Asset { id: AssetId(token_location), fun: Fungible(local_fee.into()) });
+		modified_fees.into()
+	}
+}