The Ambassador Program (#1308)

The Ambassador Program on Polkadot Collectives Parachain

The Polkadot Ambassador Program has existed for a while; more
information can be found
[here](https://wiki.polkadot.network/docs/ambassadors).
In this PR, the program is being brought on chain.

### On Chain Structure
The on-chain program consists of nine ranks, divided into four
categories ([full
list](https://github.com/paritytech/cumulus/blob/c238fb26b75569a11abb57437fd14acd26e05f18/parachains/runtimes/collectives/collectives-polkadot/src/ambassador/mod.rs#L52)):
- Ambassadors (1-2 tiers)
- Senior Ambassadors (3-4 tiers)
- Head Ambassadors (5-7 tiers)
- Master Ambassadors (8-9 tiers)

Each rank has a corresponding `Origin` (e.g., `HeadAmbassadorsTier5` -
[full
list](https://github.com/paritytech/cumulus/blob/c238fb26b75569a11abb57437fd14acd26e05f18/parachains/runtimes/collectives/collectives-polkadot/src/ambassador/origins.rs#L35)),
which represents the collective voice of members of that rank and above.

### Referendum

The `AmbassadorReferenda` instance of [referenda
pallet](https://docs.rs/pallet-referenda/latest/pallet_referenda/)
consists of [nine
tracks](https://github.com/paritytech/cumulus/blob/c238fb26b75569a11abb57437fd14acd26e05f18/parachains/runtimes/collectives/collectives-polkadot/src/ambassador/tracks.rs#L51),
each corresponding to an `Origin`. A referendum taken on `senior
ambassador tier 4` track invites all members from rank 4 or above to
vote and commands `SeniorAmbassadors` `Origin`. Every member gets one
vote plus an additional vote for every excess rank. The referendum
proposal can be submitted by any member of a senior rank or above.

### Membership Management

Initial members will be brought on chain via migration, with subsequent
member management handled through the `AmbassadorCollective` instance of
[ranked collective
pallet](https://docs.rs/pallet-ranked-collective/latest/pallet_ranked_collective/).
Both `Root` and `FellowshipAdmin` `Origins`, commanded via public
Polkadot referendum, can promote or demote members to and from any rank.
Members themselves also have the power to promote or demote via its
referendum, with a senior member vote by the rank two above the new /
current rank - [full
configuration](https://github.com/paritytech/cumulus/blob/9ab6aa47063d7e8b67ddc10d9c136037f99c03a3/parachains/runtimes/collectives/collectives-polkadot/src/ambassador/mod.rs#L67).

### Content Management

The program's on-chain content is managed via the collectives content
pallet, allowing for setting its charter and making announcements. The
voice of head ambassadors have the authority to set the charter, while
announcements can be made by any senior rank member or through a
referendum among all members.

### Additional Functionality

The `AmbassadorCore` instance of [core fellowship
pallet](https://docs.rs/pallet-core-fellowship/latest/pallet_core_fellowship/)
decorates the ranked collectives pallet with features like salary
determination, activity/passivity registration, and the handling of
promotion and demotion periods. While the usage of this pallet is
optional in the first version, future updates will make it the exclusive
method for induction/promotion.

Periodic salaries in USDt, payable on Asset Hub, are introduced through
the [salary
pallet](https://docs.rs/pallet-salary/latest/pallet_salary/). This
requires induction into the ambassador core pallet.

Please for more information on the pallets' functionality refer to their
documentations.

### Next Steps:
- Migrate to seed the program members
- Mint ambassador NFT badges on Asset Hub when promoting
- Treasury pallet instance for the Ambassador Program

---------

Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>
Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>

cumulus/parachains/common/src/polkadot.rs

@@ -27,6 +27,10 @@ pub mod account {
 	/// It is used as a temporarily place to deposit a slashed imbalance
 	/// before the teleport to the Treasury.
 	pub const REFERENDA_PALLET_ID: PalletId = PalletId(*b"py/refer");
+	/// Ambassador Referenda pallet ID.
+	/// It is used as a temporarily place to deposit a slashed imbalance
+	/// before the teleport to the Treasury.
+	pub const AMBASSADOR_REFERENDA_PALLET_ID: PalletId = PalletId(*b"py/amref");
 }
 
 /// Consensus-related.

cumulus/parachains/integration-tests/emulated/collectives/collectives-polkadot/Cargo.toml

@@ -15,6 +15,7 @@ sp-runtime = { path = "../../../../../../substrate/primitives/runtime", default-
 frame-support = { path = "../../../../../../substrate/frame/support", default-features = false}
 sp-core = { path = "../../../../../../substrate/primitives/core", default-features = false}
 pallet-assets = { path = "../../../../../../substrate/frame/assets", default-features = false}
+pallet-balances = { path = "../../../../../../substrate/frame/balances", default-features = false}
 pallet-core-fellowship = { path = "../../../../../../substrate/frame/core-fellowship", default-features = false}
 pallet-salary = { path = "../../../../../../substrate/frame/salary", default-features = false}
 

cumulus/parachains/integration-tests/emulated/collectives/collectives-polkadot/src/tests/ambassador.rs

@@ -0,0 +1,65 @@
+// Copyright (C) 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.
+
+//! Integration tests concerning the Ambassador Program.
+
+use crate::*;
+use collectives_polkadot_runtime::ambassador::AmbassadorSalaryPaymaster;
+use frame_support::traits::{fungible::Mutate, tokens::Pay};
+use sp_core::crypto::Ss58Codec;
+use xcm_emulator::TestExt;
+
+#[test]
+fn pay_salary() {
+	let pay_from: AccountId =
+		<AccountId as Ss58Codec>::from_string("5DS1Gaf6R9eFAV8QyeZP9P89kTkJMurxv3y3J3TTMu8p8VCX")
+			.unwrap();
+	let pay_to = Polkadot::account_id_of(ALICE);
+	let pay_amount = 90000000000;
+
+	AssetHubPolkadot::execute_with(|| {
+		type AssetHubBalances = <AssetHubPolkadot as AssetHubPolkadotPallet>::Balances;
+
+		assert_ok!(<AssetHubBalances as Mutate<_>>::mint_into(&pay_from, pay_amount * 2));
+	});
+
+	Collectives::execute_with(|| {
+		type RuntimeEvent = <Collectives as Chain>::RuntimeEvent;
+
+		assert_ok!(AmbassadorSalaryPaymaster::pay(&pay_to, (), pay_amount));
+		assert_expected_events!(
+			Collectives,
+			vec![
+				RuntimeEvent::XcmpQueue(cumulus_pallet_xcmp_queue::Event::XcmpMessageSent { .. }) => {},
+			]
+		);
+	});
+
+	AssetHubPolkadot::execute_with(|| {
+		type RuntimeEvent = <AssetHubPolkadot as Chain>::RuntimeEvent;
+
+		assert_expected_events!(
+			AssetHubPolkadot,
+			vec![
+				RuntimeEvent::Balances(pallet_balances::Event::Transfer { from, to, amount }) => {
+					from: from == &pay_from,
+					to: to == &pay_to,
+					amount: amount == &pay_amount,
+				},
+				RuntimeEvent::XcmpQueue(cumulus_pallet_xcmp_queue::Event::Success { .. }) => {},
+			]
+		);
+	});
+}

cumulus/parachains/integration-tests/emulated/collectives/collectives-polkadot/src/tests/mod.rs

@@ -13,4 +13,5 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+mod ambassador;
 mod fellowship;

cumulus/parachains/pallets/collective-content/Cargo.toml

@@ -0,0 +1,48 @@
+[package]
+name = "pallet-collective-content"
+version = "0.1.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2021"
+description = "Managed content"
+
+[dependencies]
+codec = { package = "parity-scale-codec", version = "3.0.0", default-features = false, features = ["derive", "max-encoded-len"] }
+scale-info = { version = "2.3.0", default-features = false, features = ["derive"] }
+
+frame-benchmarking = { path = "../../../../substrate/frame/benchmarking", optional = true, default-features = false }
+frame-support = { path = "../../../../substrate/frame/support", default-features = false }
+frame-system = { path = "../../../../substrate/frame/system", default-features = false }
+
+sp-core = { path = "../../../../substrate/primitives/core", default-features = false }
+sp-runtime = { path = "../../../../substrate/primitives/runtime", default-features = false }
+sp-std = { path = "../../../../substrate/primitives/std", default-features = false }
+
+[dev-dependencies]
+sp-io = { path = "../../../../substrate/primitives/io", default-features = false }
+
+[features]
+default = [ "std" ]
+runtime-benchmarks = [
+	"frame-benchmarking/runtime-benchmarks",
+	"frame-support/runtime-benchmarks",
+	"frame-system/runtime-benchmarks",
+	"sp-runtime/runtime-benchmarks",
+]
+
+try-runtime = [
+	"frame-support/try-runtime",
+	"frame-system/try-runtime",
+	"sp-runtime/try-runtime",
+]
+
+std = [
+	"codec/std",
+	"frame-benchmarking/std",
+	"frame-support/std",
+	"frame-system/std",
+	"scale-info/std",
+	"sp-core/std",
+	"sp-io/std",
+	"sp-runtime/std",
+	"sp-std/std",
+]

cumulus/parachains/pallets/collective-content/src/benchmarking.rs

@@ -0,0 +1,88 @@
+// Copyright (C) 2023 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.
+
+//! The pallet benchmarks.
+
+use super::{Pallet as CollectiveContent, *};
+use frame_benchmarking::{impl_benchmark_test_suite, v2::*};
+use frame_support::traits::EnsureOrigin;
+
+fn assert_last_event<T: Config<I>, I: 'static>(generic_event: <T as Config<I>>::RuntimeEvent) {
+	frame_system::Pallet::<T>::assert_last_event(generic_event.into());
+}
+
+/// returns CID hash of 68 bytes of given `i`.
+fn create_cid(i: u8) -> OpaqueCid {
+	let cid: OpaqueCid = [i; 68].to_vec().try_into().unwrap();
+	cid
+}
+
+#[instance_benchmarks]
+mod benchmarks {
+	use super::*;
+
+	#[benchmark]
+	fn set_charter() -> Result<(), BenchmarkError> {
+		let cid: OpaqueCid = create_cid(1);
+		let origin =
+			T::CharterOrigin::try_successful_origin().map_err(|_| BenchmarkError::Weightless)?;
+
+		#[extrinsic_call]
+		_(origin as T::RuntimeOrigin, cid.clone());
+
+		assert_eq!(Charter::<T, I>::get(), Some(cid.clone()));
+		assert_last_event::<T, I>(Event::NewCharterSet { cid }.into());
+		Ok(())
+	}
+
+	#[benchmark]
+	fn announce() -> Result<(), BenchmarkError> {
+		let expire_at = DispatchTime::<_>::At(10u32.into());
+		let now = frame_system::Pallet::<T>::block_number();
+		let cid: OpaqueCid = create_cid(1);
+		let origin = T::AnnouncementOrigin::try_successful_origin()
+			.map_err(|_| BenchmarkError::Weightless)?;
+
+		#[extrinsic_call]
+		_(origin as T::RuntimeOrigin, cid.clone(), Some(expire_at.clone()));
+
+		assert_eq!(<Announcements<T, I>>::count(), 1);
+		assert_last_event::<T, I>(
+			Event::AnnouncementAnnounced { cid, expire_at: expire_at.evaluate(now) }.into(),
+		);
+
+		Ok(())
+	}
+
+	#[benchmark]
+	fn remove_announcement() -> Result<(), BenchmarkError> {
+		let cid: OpaqueCid = create_cid(1);
+		let origin = T::AnnouncementOrigin::try_successful_origin()
+			.map_err(|_| BenchmarkError::Weightless)?;
+		CollectiveContent::<T, I>::announce(origin.clone(), cid.clone(), None)
+			.expect("could not publish an announcement");
+		assert_eq!(<Announcements<T, I>>::count(), 1);
+
+		#[extrinsic_call]
+		_(origin as T::RuntimeOrigin, cid.clone());
+
+		assert_eq!(<Announcements<T, I>>::count(), 0);
+		assert_last_event::<T, I>(Event::AnnouncementRemoved { cid }.into());
+
+		Ok(())
+	}
+
+	impl_benchmark_test_suite!(CollectiveContent, super::mock::new_bench_ext(), super::mock::Test);
+}