Participation Lottery Pallet

Cargo.toml

@@ -82,6 +82,7 @@ members = [
 	"frame/identity",
 	"frame/im-online",
 	"frame/indices",
+	"frame/lottery",
 	"frame/membership",
 	"frame/metadata",
 	"frame/multisig",

bin/node/runtime/Cargo.toml

@@ -57,6 +57,7 @@ pallet-grandpa = { version = "2.0.0", default-features = false, path = "../../..
 pallet-im-online = { version = "2.0.0", default-features = false, path = "../../../frame/im-online" }
 pallet-indices = { version = "2.0.0", default-features = false, path = "../../../frame/indices" }
 pallet-identity = { version = "2.0.0", default-features = false, path = "../../../frame/identity" }
+pallet-lottery = { version = "2.0.0", default-features = false, path = "../../../frame/lottery" }
 pallet-membership = { version = "2.0.0", default-features = false, path = "../../../frame/membership" }
 pallet-multisig = { version = "2.0.0", default-features = false, path = "../../../frame/multisig" }
 pallet-offences = { version = "2.0.0", default-features = false, path = "../../../frame/offences" }
@@ -107,6 +108,7 @@ std = [
 	"pallet-im-online/std",
 	"pallet-indices/std",
 	"sp-inherents/std",
+	"pallet-lottery/std",
 	"pallet-membership/std",
 	"pallet-multisig/std",
 	"pallet-identity/std",
@@ -157,6 +159,7 @@ runtime-benchmarks = [
 	"pallet-identity/runtime-benchmarks",
 	"pallet-im-online/runtime-benchmarks",
 	"pallet-indices/runtime-benchmarks",
+	"pallet-lottery/runtime-benchmarks",
 	"pallet-multisig/runtime-benchmarks",
 	"pallet-proxy/runtime-benchmarks",
 	"pallet-scheduler/runtime-benchmarks",

bin/node/runtime/src/lib.rs

@@ -892,6 +892,22 @@ impl pallet_vesting::Trait for Runtime {
 	type WeightInfo = pallet_vesting::weights::SubstrateWeight<Runtime>;
 }
 
+parameter_types! {
+	pub const LotteryModuleId: ModuleId = ModuleId(*b"py/lotto");
+	pub const MaxCalls: usize = 10;
+}
+
+impl pallet_lottery::Trait for Runtime {
+	type ModuleId = LotteryModuleId;
+	type Call = Call;
+	type Event = Event;
+	type Currency = Balances;
+	type Randomness = RandomnessCollectiveFlip;
+	type ManagerOrigin = EnsureRoot<AccountId>;
+	type MaxCalls = MaxCalls;
+	type WeightInfo = pallet_lottery::weights::SubstrateWeight<Runtime>;
+}
+
 construct_runtime!(
 	pub enum Runtime where
 		Block = Block,
@@ -929,6 +945,7 @@ construct_runtime!(
 		Scheduler: pallet_scheduler::{Module, Call, Storage, Event<T>},
 		Proxy: pallet_proxy::{Module, Call, Storage, Event<T>},
 		Multisig: pallet_multisig::{Module, Call, Storage, Event<T>},
+		Lottery: pallet_lottery::{Module, Call, Storage, Event<T>},
 	}
 );
 
@@ -1205,6 +1222,7 @@ impl_runtime_apis! {
 			add_benchmark!(params, batches, pallet_identity, Identity);
 			add_benchmark!(params, batches, pallet_im_online, ImOnline);
 			add_benchmark!(params, batches, pallet_indices, Indices);
+			add_benchmark!(params, batches, pallet_lottery, Lottery);
 			add_benchmark!(params, batches, pallet_multisig, Multisig);
 			add_benchmark!(params, batches, pallet_offences, OffencesBench::<Runtime>);
 			add_benchmark!(params, batches, pallet_proxy, Proxy);

frame/lottery/Cargo.toml

@@ -0,0 +1,42 @@
+[package]
+name = "pallet-lottery"
+version = "2.0.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+license = "Apache-2.0"
+homepage = "https://substrate.dev"
+repository = "https://github.com/paritytech/substrate/"
+description = "FRAME Participation Lottery Pallet"
+readme = "README.md"
+
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
+
+[dependencies]
+codec = { package = "parity-scale-codec", version = "1.3.4", default-features = false, features = ["derive"] }
+sp-std = { version = "2.0.0", default-features = false, path = "../../primitives/std" }
+sp-runtime = { version = "2.0.0", default-features = false, path = "../../primitives/runtime" }
+frame-support = { version = "2.0.0", default-features = false, path = "../support" }
+frame-system = { version = "2.0.0", default-features = false, path = "../system" }
+
+frame-benchmarking = { version = "2.0.0", default-features = false, path = "../benchmarking", optional = true }
+
+[dev-dependencies]
+pallet-balances = { version = "2.0.0", path = "../balances" }
+sp-core = { version = "2.0.0", path = "../../primitives/core" }
+sp-io = { version = "2.0.0", path = "../../primitives/io" }
+
+[features]
+default = ["std"]
+std = [
+	"codec/std",
+	"sp-std/std",
+	"frame-support/std",
+	"sp-runtime/std",
+	"frame-system/std",
+]
+runtime-benchmarks = [
+	"frame-benchmarking",
+	"frame-system/runtime-benchmarks",
+	"frame-support/runtime-benchmarks",
+]

frame/lottery/src/benchmarking.rs

@@ -0,0 +1,132 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2020 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Lottery pallet benchmarking.
+
+#![cfg(feature = "runtime-benchmarks")]
+
+use super::*;
+
+use frame_system::RawOrigin;
+use frame_support::traits::{OnInitialize, UnfilteredDispatchable};
+use frame_benchmarking::{benchmarks, account, whitelisted_caller};
+use sp_runtime::traits::Bounded;
+
+use crate::Module as Lottery;
+
+// Set up and start a lottery
+fn start_lottery<T: Trait>() -> Result<(), &'static str> {
+	let price = T::Currency::minimum_balance();
+	let start = 0u32.into();
+	let end = 10u32.into();
+	let payout = 15u32.into();
+	// Calls will be maximum length...
+	let mut calls = vec![
+		frame_system::Call::<T>::set_code(vec![]).into();
+		T::MaxCalls::get().saturating_sub(1)
+	];
+	// Last call will be the match for worst case scenario.
+	calls.push(frame_system::Call::<T>::remark(vec![]).into());
+	let origin = T::ManagerOrigin::successful_origin();
+	Lottery::<T>::setup_lottery(origin, price, start, end, payout, calls)?;
+	Ok(())
+}
+
+benchmarks! {
+	_ { }
+
+	setup_lottery {
+		let n in 0 .. T::MaxCalls::get() as u32;
+		let price = BalanceOf::<T>::max_value();
+		let start = 0u32.into();
+		let end = 10u32.into();
+		let payout = 15u32.into();
+		let calls = vec![frame_system::Call::<T>::remark(vec![]).into(); n as usize];
+
+		let call = Call::<T>::setup_lottery(price, start, end, payout, calls);
+		let origin = T::ManagerOrigin::successful_origin();
+	}: { call.dispatch_bypass_filter(origin)? }
+	verify {
+		assert!(crate::Lottery::<T>::get().is_some());
+	}
+
+	buy_ticket {
+		let caller = whitelisted_caller();
+		T::Currency::make_free_balance_be(&caller, BalanceOf::<T>::max_value());
+		start_lottery::<T>()?;
+		// force user to have a long vec of calls participating
+		let set_code_index: CallIndex = Lottery::<T>::call_to_index(
+			&frame_system::Call::<T>::set_code(vec![]).into()
+		)?;
+		let already_called: (Index, Vec<CallIndex>) = (
+			LotteryIndex::get(),
+			vec![
+				set_code_index;
+				T::MaxCalls::get().saturating_sub(1)
+			],
+		);
+		Participants::<T>::insert(&caller, already_called);
+
+		let call = frame_system::Call::<T>::remark(vec![]);
+	}: _(RawOrigin::Signed(caller), Box::new(call.into()))
+	verify {
+		assert_eq!(TicketsCount::get(), 1);
+	}
+
+	on_initialize {
+		start_lottery::<T>()?;
+		let winner = account("winner", 0, 0);
+		// User needs more than min balance to get ticket
+		T::Currency::make_free_balance_be(&winner, T::Currency::minimum_balance() * 10u32.into());
+		// Make sure lottery account has at least min balance too
+		let lottery_account = Lottery::<T>::account_id();
+		T::Currency::make_free_balance_be(&lottery_account, T::Currency::minimum_balance() * 10u32.into());
+		// Buy a ticket
+		let call = frame_system::Call::<T>::remark(vec![]);
+		Lottery::<T>::buy_ticket(RawOrigin::Signed(winner.clone()).into(), Box::new(call.into()))?;
+		// Kill user account for worst case
+		T::Currency::make_free_balance_be(&winner, 0u32.into());
+		// Assert that lotto is set up for winner
+		assert_eq!(TicketsCount::get(), 1);
+		assert!(!Lottery::<T>::pot().1.is_zero());
+	}: {
+		// Start lottery has block 15 configured for payout
+		Lottery::<T>::on_initialize(15u32.into());
+	}
+	verify {
+		assert!(crate::Lottery::<T>::get().is_none());
+		assert_eq!(TicketsCount::get(), 0);
+		assert_eq!(Lottery::<T>::pot().1, 0u32.into());
+		assert!(!T::Currency::free_balance(&winner).is_zero())
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+	use crate::mock::{new_test_ext, Test};
+	use frame_support::assert_ok;
+
+	#[test]
+	fn test_benchmarks() {
+		new_test_ext().execute_with(|| {
+			assert_ok!(test_benchmark_setup_lottery::<Test>());
+			assert_ok!(test_benchmark_buy_ticket::<Test>());
+			assert_ok!(test_benchmark_on_initialize::<Test>());
+		});
+	}
+}