Westend: Fellowship Treasury (#2532)

Treasury Pallet Instance for the Fellowship in Westend Collectives.

In this update, we present a Treasury Pallet Instance that is under the
control of the Fellowship body, with oversight from the Root and
Treasurer origins. Here's how it is governed:
- the Root origin have the authority to reject or approve spend
proposals, with no amount limit for approvals.
- the Treasurer origin have the authority to reject or approve spend
proposals, with approval limits of up to 10,000,000 DOT.
- Voice of all Fellows ranked at 3 or above can reject or approve spend
proposals, with a maximum approval limit of 10,000 DOT.
- Voice of Fellows ranked at 4 or above can also reject or approve spend
proposals, with a maximum approval limit of 10,000,000 DOT.

Additionally, we introduce the Asset Rate Pallet Instance to establish
conversion rates from asset A to B. This is used to determine if a
proposed spend amount involving a non-native asset is permissible by the
commanding origin. The rates can be set up by the Root, Treasurer
origins, or Voice of all Fellows.

---------

Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>
Co-authored-by: joepetrowski <joe@parity.io>

cumulus/parachains/runtimes/collectives/collectives-westend/src/fellowship/mod.rs

@@ -21,28 +21,41 @@ mod tracks;
 use crate::{
 	impls::ToParentTreasury,
 	weights,
-	xcm_config::{FellowshipAdminBodyId, UsdtAssetHub},
-	AccountId, Balance, Balances, FellowshipReferenda, GovernanceLocation, Preimage, Runtime,
-	RuntimeCall, RuntimeEvent, RuntimeOrigin, Scheduler, WestendTreasuryAccount, DAYS,
+	xcm_config::{FellowshipAdminBodyId, TreasurerBodyId, UsdtAssetHub},
+	AccountId, AssetRate, Balance, Balances, FellowshipReferenda, GovernanceLocation, Preimage,
+	Runtime, RuntimeCall, RuntimeEvent, RuntimeOrigin, Scheduler, WestendTreasuryAccount, DAYS,
 };
 use frame_support::{
 	parameter_types,
-	traits::{EitherOf, EitherOfDiverse, MapSuccess, OriginTrait, TryWithMorphedArg},
+	traits::{
+		EitherOf, EitherOfDiverse, MapSuccess, NeverEnsureOrigin, OriginTrait, TryWithMorphedArg,
+	},
+	PalletId,
 };
-use frame_system::EnsureRootWithSuccess;
+use frame_system::{EnsureRoot, EnsureRootWithSuccess};
 pub use origins::{
 	pallet_origins as pallet_fellowship_origins, Architects, EnsureCanPromoteTo, EnsureCanRetainAt,
 	EnsureFellowship, Fellows, Masters, Members, ToVoice,
 };
 use pallet_ranked_collective::EnsureOfRank;
 use pallet_xcm::{EnsureXcm, IsVoiceOfBody};
-use parachains_common::{polkadot::account, HOURS};
+use parachains_common::westend::{account, currency::GRAND};
+use polkadot_runtime_common::impls::{
+	LocatableAssetConverter, VersionedLocatableAsset, VersionedMultiLocationConverter,
+};
+use sp_arithmetic::Permill;
 use sp_core::{ConstU128, ConstU32};
-use sp_runtime::traits::{AccountIdConversion, ConstU16, ConvertToValue, Replace, TakeFirst};
+use sp_runtime::traits::{
+	AccountIdConversion, ConstU16, ConvertToValue, IdentityLookup, Replace, TakeFirst,
+};
+use westend_runtime_constants::time::HOURS;
+use xcm::prelude::*;
 use xcm_builder::{AliasesIntoAccountId32, PayOverXcm};
 
 #[cfg(feature = "runtime-benchmarks")]
 use crate::impls::benchmarks::{OpenHrmpChannel, PayWithEnsure};
+#[cfg(feature = "runtime-benchmarks")]
+use parachains_common::westend::currency::DOLLARS;
 
 /// The Fellowship members' ranks.
 pub mod ranks {
@@ -191,8 +204,6 @@ impl pallet_core_fellowship::Config<FellowshipCoreInstance> for Runtime {
 
 pub type FellowshipSalaryInstance = pallet_salary::Instance1;
 
-use xcm::prelude::*;
-
 parameter_types! {
 	// The interior location on AssetHub for the paying account. This is the Fellowship Salary
 	// pallet instance (which sits at index 64). This sovereign account will need funding.
@@ -236,3 +247,102 @@ impl pallet_salary::Config<FellowshipSalaryInstance> for Runtime {
 	// Total monthly salary budget.
 	type Budget = ConstU128<{ 100_000 * USDT_UNITS }>;
 }
+
+parameter_types! {
+	pub const FellowshipTreasuryPalletId: PalletId = account::FELLOWSHIP_TREASURY_PALLET_ID;
+	pub const HundredPercent: Permill = Permill::from_percent(100);
+	pub const Burn: Permill = Permill::from_percent(0);
+	pub const MaxBalance: Balance = Balance::max_value();
+	// The asset's interior location for the paying account. This is the Fellowship Treasury
+	// pallet instance (which sits at index 65).
+	pub FellowshipTreasuryInteriorLocation: InteriorMultiLocation = PalletInstance(65).into();
+}
+
+#[cfg(feature = "runtime-benchmarks")]
+parameter_types! {
+	// Benchmark bond. Needed to make `propose_spend` work.
+	pub const TenPercent: Permill = Permill::from_percent(10);
+	// Benchmark minimum. Needed to make `propose_spend` work.
+	pub const BenchmarkProposalBondMinimum: Balance = 1 * DOLLARS;
+	// Benchmark maximum. Needed to make `propose_spend` work.
+	pub const BenchmarkProposalBondMaximum: Balance = 10 * DOLLARS;
+}
+
+/// [`PayOverXcm`] setup to pay the Fellowship Treasury.
+pub type FellowshipTreasuryPaymaster = PayOverXcm<
+	FellowshipTreasuryInteriorLocation,
+	crate::xcm_config::XcmRouter,
+	crate::PolkadotXcm,
+	ConstU32<{ 6 * HOURS }>,
+	VersionedMultiLocation,
+	VersionedLocatableAsset,
+	LocatableAssetConverter,
+	VersionedMultiLocationConverter,
+>;
+
+pub type FellowshipTreasuryInstance = pallet_treasury::Instance1;
+
+impl pallet_treasury::Config<FellowshipTreasuryInstance> for Runtime {
+	// The creation of proposals via the treasury pallet is deprecated and should not be utilized.
+	// Instead, public or fellowship referenda should be used to propose and command the treasury
+	// spend or spend_local dispatchables. The parameters below have been configured accordingly to
+	// discourage its use.
+	// TODO: replace with `NeverEnsure` once polkadot-sdk 1.5 is released.
+	type ApproveOrigin = NeverEnsureOrigin<()>;
+	type OnSlash = ();
+	#[cfg(not(feature = "runtime-benchmarks"))]
+	type ProposalBond = HundredPercent;
+	#[cfg(not(feature = "runtime-benchmarks"))]
+	type ProposalBondMinimum = MaxBalance;
+	#[cfg(not(feature = "runtime-benchmarks"))]
+	type ProposalBondMaximum = MaxBalance;
+
+	#[cfg(feature = "runtime-benchmarks")]
+	type ProposalBond = TenPercent;
+	#[cfg(feature = "runtime-benchmarks")]
+	type ProposalBondMinimum = BenchmarkProposalBondMinimum;
+	#[cfg(feature = "runtime-benchmarks")]
+	type ProposalBondMaximum = BenchmarkProposalBondMaximum;
+	// end.
+
+	type WeightInfo = weights::pallet_treasury::WeightInfo<Runtime>;
+	type PalletId = FellowshipTreasuryPalletId;
+	type Currency = Balances;
+	type RejectOrigin = EitherOfDiverse<
+		EnsureRoot<AccountId>,
+		EitherOfDiverse<EnsureXcm<IsVoiceOfBody<GovernanceLocation, TreasurerBodyId>>, Fellows>,
+	>;
+	type RuntimeEvent = RuntimeEvent;
+	type SpendPeriod = ConstU32<{ 7 * DAYS }>;
+	type Burn = Burn;
+	type BurnDestination = ();
+	type SpendFunds = ();
+	type MaxApprovals = ConstU32<100>;
+	type SpendOrigin = EitherOf<
+		EitherOf<
+			EnsureRootWithSuccess<AccountId, MaxBalance>,
+			MapSuccess<
+				EnsureXcm<IsVoiceOfBody<GovernanceLocation, TreasurerBodyId>>,
+				Replace<ConstU128<{ 10_000 * GRAND }>>,
+			>,
+		>,
+		EitherOf<
+			MapSuccess<Architects, Replace<ConstU128<{ 10_000 * GRAND }>>>,
+			MapSuccess<Fellows, Replace<ConstU128<{ 10 * GRAND }>>>,
+		>,
+	>;
+	type AssetKind = VersionedLocatableAsset;
+	type Beneficiary = VersionedMultiLocation;
+	type BeneficiaryLookup = IdentityLookup<Self::Beneficiary>;
+	#[cfg(not(feature = "runtime-benchmarks"))]
+	type Paymaster = FellowshipTreasuryPaymaster;
+	#[cfg(feature = "runtime-benchmarks")]
+	type Paymaster = PayWithEnsure<FellowshipTreasuryPaymaster, OpenHrmpChannel<ConstU32<1000>>>;
+	type BalanceConverter = AssetRate;
+	type PayoutPeriod = ConstU32<{ 30 * DAYS }>;
+	#[cfg(feature = "runtime-benchmarks")]
+	type BenchmarkHelper = polkadot_runtime_common::impls::benchmarks::TreasuryArguments<
+		sp_core::ConstU8<1>,
+		ConstU32<1000>,
+	>;
+}