liquid-crowdloan

modules/liquid-crowdloan/Cargo.toml

@@ -0,0 +1,41 @@
+[package]
+name = "module-liquid-crowdloan"
+version = "2.16.0"
+authors = ["Acala Developers"]
+edition = "2021"
+
+[dependencies]
+scale-info = { version = "2.2.0", default-features = false, features = ["derive"] }
+codec = { package = "parity-scale-codec", version = "3.0.0", default-features = false }
+
+sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.38", default-features = false }
+frame-support = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.38", default-features = false }
+frame-system = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.38", default-features = false }
+
+orml-traits = { path = "../../orml/traits", default-features = false }
+primitives = { package = "acala-primitives", path = "../../primitives", default-features = false }
+support = { package = "module-support", path = "../support", default-features = false }
+
+[dev-dependencies]
+sp-core = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.38" }
+sp-io = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.38" }
+pallet-balances = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.38" }
+module-currencies = { path = "../currencies" }
+orml-tokens = { path = "../../orml/tokens" }
+
+[features]
+default = ["std"]
+std = [
+	"codec/std",
+	"scale-info/std",
+	"sp-runtime/std",
+	"frame-support/std",
+	"frame-system/std",
+	"orml-traits/std",
+	"primitives/std",
+	"support/std",
+]
+try-runtime = [
+	"frame-support/try-runtime",
+	"frame-system/try-runtime",
+]

modules/liquid-crowdloan/src/lib.rs

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+// This file is part of Acala.
+
+// Copyright (C) 2020-2023 Acala Foundation.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program 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.
+
+// This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! # Liquid Crowdloan Module
+//!
+//! Allow people to redeem lcDOT for DOT.
+
+#![cfg_attr(not(feature = "std"), no_std)]
+#![allow(clippy::unused_unit)]
+
+use frame_support::{pallet_prelude::*, traits::EnsureOrigin, PalletId};
+use frame_system::pallet_prelude::*;
+use orml_traits::MultiCurrency;
+use primitives::{Balance, CurrencyId};
+use sp_runtime::traits::AccountIdConversion;
+
+use support::CrowdloanVaultXcm;
+
+mod mock;
+mod tests;
+
+pub use module::*;
+
+#[frame_support::pallet]
+pub mod module {
+	use super::*;
+
+	#[pallet::config]
+	pub trait Config: frame_system::Config {
+		type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
+
+		type Currency: MultiCurrency<Self::AccountId, CurrencyId = CurrencyId, Balance = Balance>;
+
+		/// Liquid crowdloan currency Id, i.e. LDOT for Polkadot.
+		#[pallet::constant]
+		type LiquidCrowdloanCurrencyId: Get<CurrencyId>;
+
+		/// Relay chain currency Id, i.e. DOT for Polkadot.
+		#[pallet::constant]
+		type RelayChainCurrencyId: Get<CurrencyId>;
+
+		/// Pallet Id for liquid crowdloan module.
+		#[pallet::constant]
+		type PalletId: Get<PalletId>;
+
+		/// The governance origin for liquid crowdloan module. For instance for DOT cross-chain
+		/// transfer DOT from relay chain crowdloan vault to liquid crowdloan module account.
+		type GovernanceOrigin: EnsureOrigin<Self::RuntimeOrigin>;
+
+		/// The crowdloan vault account on relay chain.
+		#[pallet::constant]
+		type CrowdloanVault: Get<Self::AccountId>;
+
+		/// XCM transfer impl.
+		type XcmTransfer: CrowdloanVaultXcm<Self::AccountId, Balance>;
+	}
+
+	#[pallet::event]
+	#[pallet::generate_deposit(fn deposit_event)]
+	pub enum Event<T: Config> {
+		/// Liquid Crowdloan asset was redeemed.
+		Redeemed { amount: Balance },
+		/// The transfer from relay chain crowdloan vault was requested.
+		TransferFromCrowdloanVaultRequested { amount: Balance },
+	}
+
+	#[pallet::pallet]
+	pub struct Pallet<T>(_);
+	#[pallet::call]
+	impl<T: Config> Pallet<T> {
+		/// Redeem liquid crowdloan currency for relay chain currency.
+		#[pallet::call_index(0)]
+		#[pallet::weight(0)]
+		pub fn redeem(origin: OriginFor<T>, #[pallet::compact] amount: Balance) -> DispatchResult {
+			let who = ensure_signed(origin)?;
+
+			T::Currency::withdraw(T::LiquidCrowdloanCurrencyId::get(), &who, amount)?;
+
+			T::Currency::transfer(T::RelayChainCurrencyId::get(), &Self::account_id(), &who, amount)?;
+
+			Self::deposit_event(Event::Redeemed { amount });
+
+			Ok(())
+		}
+
+		/// Send an XCM message to cross-chain transfer DOT from relay chain crowdloan vault to
+		///  liquid crowdloan module account.
+		///
+		/// This call requires `GovernanceOrigin`.
+		#[pallet::call_index(1)]
+		#[pallet::weight(0)]
+		pub fn transfer_from_crowdloan_vault(
+			origin: OriginFor<T>,
+			#[pallet::compact] amount: Balance,
+		) -> DispatchResult {
+			T::GovernanceOrigin::ensure_origin(origin)?;
+
+			T::XcmTransfer::transfer_to_liquid_crowdloan_module_account(
+				T::CrowdloanVault::get(),
+				Self::account_id(),
+				amount,
+			)?;
+
+			Self::deposit_event(Event::TransferFromCrowdloanVaultRequested { amount });
+
+			Ok(())
+		}
+	}
+}
+
+impl<T: Config> Pallet<T> {
+	pub fn account_id() -> T::AccountId {
+		T::PalletId::get().into_account_truncating()
+	}
+}