The Ambassador Program

Cargo.toml

@@ -30,6 +30,7 @@ members = [
 	"primitives/utility",
 	"polkadot-parachain",
 	"parachains/common",
+	"parachains/pallets/collective-content",
 	"parachains/pallets/parachain-info",
 	"parachains/pallets/ping",
 	"parachains/runtimes/testing/rococo-parachain",

parachains/pallets/collective-content/Cargo.toml

@@ -0,0 +1,40 @@
+[package]
+name = "pallet-collective-content"
+version = "0.1.0"
+authors = ["Parity Technologies <[email protected]>"]
+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 = { git = "https://github.com/paritytech/substrate", optional = true, default-features = false, branch = "master" }
+frame-support = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
+frame-system = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
+
+sp-core = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
+sp-runtime = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
+sp-std = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
+
+[dev-dependencies]
+sp-io = { git = "https://github.com/paritytech/substrate", branch = "master" }
+
+[features]
+default = [ "std" ]
+runtime-benchmarks = [
+	"frame-benchmarking/runtime-benchmarks",
+	"frame-support/runtime-benchmarks",
+	"frame-system/runtime-benchmarks",
+	"sp-runtime/runtime-benchmarks",
+]
+
+std = [
+	"codec/std",
+	"scale-info/std",
+	"frame-support/std",
+	"frame-system/std",
+	"sp-core/std",
+	"sp-runtime/std",
+	"sp-std/std",
+]

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

@@ -0,0 +1,68 @@
+// 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::benchmarks_instance_pallet;
+use frame_support::traits::{EnsureOrigin, UnfilteredDispatchable};
+use sp_core::Get;
+use sp_std::vec;
+
+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());
+}
+
+benchmarks_instance_pallet! {
+	set_charter {
+		let cid: Cid = b"ipfs_hash".to_vec().try_into().unwrap();
+		let call = Call::<T, I>::set_charter { cid: cid.clone() };
+		let origin = T::CharterOrigin::successful_origin();
+	}: { call.dispatch_bypass_filter(origin)? }
+	verify {
+		assert_eq!(CollectiveContent::<T, I>::charter(), Some(cid.clone()));
+		assert_last_event::<T, I>(Event::NewCharterSet { cid }.into());
+	}
+
+	announce {
+		let cid: Cid = b"ipfs_hash".to_vec().try_into().unwrap();
+		let call = Call::<T, I>::announce { cid: cid.clone() };
+		let origin = T::AnnouncementOrigin::successful_origin();
+	}: { call.dispatch_bypass_filter(origin)? }
+	verify {
+		assert_eq!(CollectiveContent::<T, I>::announcements().len(), 1);
+		assert_last_event::<T, I>(Event::AnnouncementAnnounced { cid }.into());
+	}
+
+	remove_announcement {
+		let cid: Cid = b"ipfs_hash".to_vec().try_into().unwrap();
+		let origin = T::AnnouncementOrigin::successful_origin();
+		let max_count = T::MaxAnnouncementsCount::get() as usize;
+
+		// fill the announcements vec for the worst case.
+		let announcements = vec![cid.clone(); max_count];
+		let announcements: BoundedVec<_, T::MaxAnnouncementsCount> = BoundedVec::try_from(announcements).unwrap();
+		Announcements::<T, I>::put(announcements);
+		assert_eq!(CollectiveContent::<T, I>::announcements().len(), max_count);
+
+		let call = Call::<T, I>::remove_announcement { cid: cid.clone() };
+	}: { call.dispatch_bypass_filter(origin)? }
+	verify {
+		assert_eq!(CollectiveContent::<T, I>::announcements().len(), max_count - 1);
+		assert_last_event::<T, I>(Event::AnnouncementRemoved { cid }.into());
+	}
+
+	impl_benchmark_test_suite!(CollectiveContent, super::mock::new_bench_ext(), super::mock::Test);
+}

parachains/pallets/collective-content/src/lib.rs

@@ -0,0 +1,181 @@
+// 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.
+
+//! Managed collective content.
+//!
+//! The pallet provides the functionality to store different types of the content.
+//! The content presented as a [Cid] of the IPFS document which might contain any type of data.
+//! Every type of the content has its own origin to be manage. The origins are configurable by clients.
+//! Storing the content does not require a deposit, the content expected to be managed by a trusted collective.
+//!
+//! Content types:
+//! - the collective [charter](pallet::Charter). A single document managed by [CharterOrigin](pallet::Config::CharterOrigin).
+//! - the collective [announcements](pallet::Announcements). A list of announcements managed by [AnnouncementOrigin](pallet::Config::AnnouncementOrigin).
+
+#![cfg_attr(not(feature = "std"), no_std)]
+
+#[cfg(test)]
+mod mock;
+#[cfg(test)]
+mod tests;
+
+#[cfg(feature = "runtime-benchmarks")]
+mod benchmarking;
+pub mod weights;
+
+pub use pallet::*;
+pub use weights::WeightInfo;
+
+use frame_support::BoundedVec;
+use sp_core::ConstU32;
+
+/// IPFS compatible CID.
+// worst case 2 bytes base and codec, 2 bytes hash type and size, 64 bytes hash digest.
+pub type Cid = BoundedVec<u8, ConstU32<68>>;
+
+#[frame_support::pallet]
+pub mod pallet {
+	use super::{Cid, WeightInfo};
+	use frame_support::pallet_prelude::*;
+	use frame_system::pallet_prelude::*;
+
+	/// The current storage version.
+	const STORAGE_VERSION: StorageVersion = StorageVersion::new(0);
+
+	#[pallet::pallet]
+	#[pallet::generate_store(pub (super) trait Store)]
+	#[pallet::storage_version(STORAGE_VERSION)]
+	pub struct Pallet<T, I = ()>(PhantomData<(T, I)>);
+
+	/// The module configuration trait.
+	#[pallet::config]
+	pub trait Config<I: 'static = ()>: frame_system::Config {
+		/// The overarching event type.
+		type RuntimeEvent: From<Event<Self, I>>
+			+ IsType<<Self as frame_system::Config>::RuntimeEvent>;
+
+		/// The origin to control the collective announcements.
+		type AnnouncementOrigin: EnsureOrigin<Self::RuntimeOrigin>;
+
+		/// The origin to control the collective charter.
+		type CharterOrigin: EnsureOrigin<Self::RuntimeOrigin>;
+
+		/// The maximum number of announcements.
+		#[pallet::constant]
+		type MaxAnnouncementsCount: Get<u32>;
+
+		/// Weights information needed for the pallet.
+		type WeightInfo: WeightInfo;
+	}
+
+	/// Errors encountered by the pallet (not a full list).
+	#[pallet::error]
+	pub enum Error<T, I = ()> {
+		/// The announcement is not found.
+		MissingAnnouncement,
+		/// Number of announcements exceeds `MaxAnnouncementsCount`.
+		TooManyAnnouncements,
+	}
+
+	/// Events emitted by the pallet.
+	#[pallet::event]
+	#[pallet::generate_deposit(pub(super) fn deposit_event)]
+	pub enum Event<T: Config<I>, I: 'static = ()> {
+		/// A new charter has been set.
+		NewCharterSet { cid: Cid },
+		/// A new announcement has been proposed.
+		AnnouncementAnnounced { cid: Cid },
+		/// An on-chain announcement has been removed.
+		AnnouncementRemoved { cid: Cid },
+	}
+
+	/// The collective charter.
+	#[pallet::storage]
+	#[pallet::getter(fn charter)]
+	pub type Charter<T: Config<I>, I: 'static = ()> = StorageValue<_, Cid, OptionQuery>;
+
+	/// The collective announcements.
+	#[pallet::storage]
+	#[pallet::getter(fn announcements)]
+	pub type Announcements<T: Config<I>, I: 'static = ()> =
+		StorageValue<_, BoundedVec<Cid, T::MaxAnnouncementsCount>, ValueQuery>;
+
+	#[pallet::call]
+	impl<T: Config<I>, I: 'static> Pallet<T, I> {
+		/// Set the collective  charter.
+		///
+		/// Parameters:
+		/// - `origin`: Must be the [T::CharterOrigin].
+		/// - `cid`: [CID](super::Cid) of the IPFS document of the collective charter.
+		///
+		/// Weight: `O(1)`.
+		#[pallet::call_index(0)]
+		#[pallet::weight(T::WeightInfo::set_charter())]
+		pub fn set_charter(origin: OriginFor<T>, cid: Cid) -> DispatchResult {
+			T::CharterOrigin::ensure_origin(origin)?;
+
+			Charter::<T, I>::put(&cid);
+
+			Self::deposit_event(Event::<T, I>::NewCharterSet { cid });
+			Ok(())
+		}
+
+		/// Publish an announcement.
+		///
+		/// Parameters:
+		/// - `origin`: Must be the [T::CharterOrigin].
+		/// - `cid`: [CID](super::Cid) of the IPFS document to announce.
+		///
+		/// Weight: `O(1)`.
+		#[pallet::call_index(1)]
+		#[pallet::weight(T::WeightInfo::announce())]
+		pub fn announce(origin: OriginFor<T>, cid: Cid) -> DispatchResult {
+			T::AnnouncementOrigin::ensure_origin(origin)?;
+
+			let mut announcements = <Announcements<T, I>>::get();
+			announcements
+				.try_push(cid.clone())
+				.map_err(|_| Error::<T, I>::TooManyAnnouncements)?;
+			<Announcements<T, I>>::put(announcements);
+
+			Self::deposit_event(Event::<T, I>::AnnouncementAnnounced { cid });
+			Ok(())
+		}
+
+		/// Remove an announcement.
+		///
+		/// Parameters:
+		/// - `origin`: Must be the [T::CharterOrigin].
+		/// - `cid`: [CID](super::Cid) of the IPFS document to remove.
+		///
+		/// Weight: `O(1)`, less of the [T::MaxAnnouncementsCount] is lower.
+		#[pallet::call_index(2)]
+		#[pallet::weight(T::WeightInfo::remove_announcement())]
+		pub fn remove_announcement(origin: OriginFor<T>, cid: Cid) -> DispatchResult {
+			T::AnnouncementOrigin::ensure_origin(origin)?;
+
+			let mut announcements = <Announcements<T, I>>::get();
+			let pos = announcements
+				.binary_search(&cid)
+				.ok()
+				.ok_or(Error::<T, I>::MissingAnnouncement)?;
+			announcements.remove(pos);
+			<Announcements<T, I>>::put(announcements);
+
+			Self::deposit_event(Event::<T, I>::AnnouncementRemoved { cid });
+			Ok(())
+		}
+	}
+}