Mesh 2104/add mediator (#1584)

* Add add_mandatory_mediators and remove_mediators extrinsics

* Add mediators to InstructionInfo; Derive default

* Add InstructionMediatorsAffirmations storage; Set storage when adding a new instruction; Check mediator's affirmation expiry before executing

* Add affirm_instruction_as_mediator and remove_affirmation_as_mediator extrinsics; Remove migrations

* Add add_instruction_with_mediators; Add benchmarks; Change prune instruction

* Cargo fmt

* Add unit tests for the new extrinsics

* Add events

* Add expired_affirmation_execution unit test

* Add missing weights; Add add_and_affirm_with_mediators extrinsic

* Add mediators to execute instruction benchmarks; Rename functions

* Fix test function

* Add reject_instruction_as_mediator extrinsic

* Add mediators set to events

* Remove duplicated import

* Remove duplicated line in tests

---------

Co-authored-by: Robert Gabriel Jakabosky <[email protected]>

pallets/asset/src/benchmarking.rs

@@ -16,6 +16,8 @@
 use frame_benchmarking::benchmarks;
 use frame_support::StorageValue;
 use frame_system::RawOrigin;
+use scale_info::prelude::format;
+use sp_std::collections::btree_set::BTreeSet;
 use sp_std::{convert::TryInto, iter, prelude::*};
 
 use pallet_portfolio::{NextPortfolioNumber, PortfolioAssetBalances};
@@ -185,7 +187,8 @@ pub fn setup_asset_transfer<T>(
     receiver_portolfio_name: Option<&str>,
     pause_compliance: bool,
     pause_restrictions: bool,
-) -> (PortfolioId, PortfolioId)
+    n_mediators: u8,
+) -> (PortfolioId, PortfolioId, Vec<User<T>>)
 where
     T: Config + TestUtilsFn<AccountIdOf<T>>,
 {
@@ -198,6 +201,26 @@ where
     make_asset::<T>(sender, Some(ticker.as_ref()));
     move_from_default_portfolio::<T>(sender, ticker, ONE_UNIT * POLY, sender_portfolio);
 
+    // Sets mandatory mediators
+    let mut asset_mediators = Vec::new();
+    if n_mediators > 0 {
+        let mediators_identity: BTreeSet<IdentityId> = (0..n_mediators)
+            .map(|i| {
+                let mediator = UserBuilder::<T>::default()
+                    .generate_did()
+                    .build(&format!("Mediator{:?}{}", ticker, i));
+                asset_mediators.push(mediator.clone());
+                mediator.did()
+            })
+            .collect();
+        Module::<T>::add_mandatory_mediators(
+            sender.origin().into(),
+            ticker,
+            mediators_identity.try_into().unwrap(),
+        )
+        .unwrap();
+    }
+
     // Adds the maximum number of compliance requirement
     // If pause_compliance is true, only the decoding cost will be considered.
     T::ComplianceManager::setup_ticker_compliance(sender.did(), ticker, 50, pause_compliance);
@@ -212,7 +235,7 @@ where
         pause_restrictions,
     );
 
-    (sender_portfolio, receiver_portfolio)
+    (sender_portfolio, receiver_portfolio, asset_mediators)
 }
 
 /// Creates a user portfolio for `user`.
@@ -618,8 +641,8 @@ benchmarks! {
         let ticker: Ticker = Ticker::from_slice_truncated(b"TICKER".as_ref());
         let mut weight_meter = WeightMeter::max_limit_no_minimum();
 
-        let (sender_portfolio, receiver_portfolio) =
-            setup_asset_transfer::<T>(&alice, &bob, ticker, None, None, true, true);
+        let (sender_portfolio, receiver_portfolio, _) =
+            setup_asset_transfer::<T>(&alice, &bob, ticker, None, None, true, true, 0);
     }: {
         Module::<T>::base_transfer(
             sender_portfolio,
@@ -653,4 +676,48 @@ benchmarks! {
         let ticker: Ticker = Ticker::from_slice_truncated(b"TICKER".as_ref());
         Module::<T>::pre_approve_ticker(alice.clone().origin().into(), ticker).unwrap();
     }: _(alice.origin, ticker)
+
+    add_mandatory_mediators {
+        let n in 1 .. T::MaxAssetMediators::get() as u32;
+
+        let alice = UserBuilder::<T>::default().generate_did().build("Alice");
+        let ticker: Ticker = Ticker::from_slice_truncated(b"TICKER".as_ref());
+        let mediators: BTreeSet<IdentityId> = (0..n).map(|i| IdentityId::from(i as u128)).collect();
+
+        Module::<T>::create_asset(
+            alice.clone().origin().into(),
+            ticker.as_ref().into(),
+            ticker,
+            false,
+            AssetType::NonFungible(NonFungibleType::Derivative),
+            Vec::new(),
+            None,
+        ).unwrap();
+
+    }: _(alice.origin, ticker, mediators.try_into().unwrap())
+
+    remove_mandatory_mediators {
+        let n in 1 .. T::MaxAssetMediators::get() as u32;
+
+        let alice = UserBuilder::<T>::default().generate_did().build("Alice");
+        let ticker: Ticker = Ticker::from_slice_truncated(b"TICKER".as_ref());
+        let mediators: BTreeSet<IdentityId> = (0..n).map(|i| IdentityId::from(i as u128)).collect();
+
+        Module::<T>::create_asset(
+            alice.clone().origin().into(),
+            ticker.as_ref().into(),
+            ticker,
+            false,
+            AssetType::NonFungible(NonFungibleType::Derivative),
+            Vec::new(),
+            None,
+        ).unwrap();
+
+        Module::<T>::add_mandatory_mediators(
+            alice.clone().origin().into(),
+            ticker,
+            mediators.clone().try_into().unwrap()
+        ).unwrap();
+    }: _(alice.origin, ticker, mediators.try_into().unwrap())
+
 }

pallets/asset/src/lib.rs

@@ -84,13 +84,17 @@ pub mod checkpoint;
 #[cfg(feature = "std")]
 use sp_runtime::{Deserialize, Serialize};
 
+#[cfg(feature = "runtime-benchmarks")]
+use sp_std::collections::btree_set::BTreeSet;
+
 use arrayvec::ArrayVec;
 use codec::{Decode, Encode};
 use core::mem;
 use core::result::Result as StdResult;
 use currency::*;
 use frame_support::dispatch::{DispatchError, DispatchResult, Weight};
 use frame_support::traits::{Get, PalletInfoAccess};
+use frame_support::BoundedBTreeSet;
 use frame_support::{decl_error, decl_module, decl_storage, ensure, fail};
 use frame_system::ensure_root;
 use scale_info::TypeInfo;
@@ -291,6 +295,10 @@ decl_storage! {
         pub PreApprovedTicker get(fn pre_approved_tickers):
             double_map hasher(identity) IdentityId, hasher(blake2_128_concat) Ticker => bool;
 
+        /// The list of mandatory mediators for every ticker.
+        pub MandatoryMediators get(fn mandatory_mediators):
+            map hasher(blake2_128_concat) Ticker => BoundedBTreeSet<IdentityId, T::MaxAssetMediators>;
+
         /// Storage version.
         StorageVersion get(fn storage_version) build(|_| Version::new(3)): Version;
     }
@@ -893,6 +901,42 @@ decl_module! {
         pub fn remove_ticker_pre_approval(origin, ticker: Ticker) -> DispatchResult {
             Self::base_remove_ticker_pre_approval(origin, ticker)
         }
+
+        /// Sets all identities in the `mediators` set as mandatory mediators for any instruction transfering `ticker`.
+        ///
+        /// # Arguments
+        /// * `origin`: The secondary key of the sender.
+        /// * `ticker`: The [`Ticker`] of the asset that will require the mediators.
+        /// * `mediators`: A set of [`IdentityId`] of all the mandatory mediators for the given ticker.
+        ///
+        /// # Permissions
+        /// * Asset
+        #[weight = <T as Config>::WeightInfo::add_mandatory_mediators(mediators.len() as u32)]
+        pub fn add_mandatory_mediators(
+            origin,
+            ticker: Ticker,
+            mediators: BoundedBTreeSet<IdentityId, T::MaxAssetMediators>
+        ) {
+            Self::base_add_mandatory_mediators(origin, ticker, mediators)?;
+        }
+
+        /// Removes all identities in the `mediators` set from the mandatory mediators list for the given `ticker`.
+        ///
+        /// # Arguments
+        /// * `origin`: The secondary key of the sender.
+        /// * `ticker`: The [`Ticker`] of the asset that will have mediators removed.
+        /// * `mediators`: A set of [`IdentityId`] of all the mediators that will be removed from the mandatory mediators list.
+        ///
+        /// # Permissions
+        /// * Asset
+        #[weight = <T as Config>::WeightInfo::remove_mandatory_mediators(mediators.len() as u32)]
+        pub fn remove_mandatory_mediators(
+            origin,
+            ticker: Ticker,
+            mediators: BoundedBTreeSet<IdentityId, T::MaxAssetMediators>
+        ) {
+            Self::base_remove_mandatory_mediators(origin, ticker, mediators)?;
+        }
     }
 }
 
@@ -972,6 +1016,8 @@ decl_error! {
         AssetMetadataKeyBelongsToNFTCollection,
         /// Attempt to lock a metadata value that is empty.
         AssetMetadataValueIsEmpty,
+        /// Number of asset mediators would exceed the maximum allowed.
+        NumberOfAssetMediatorsExceeded,
     }
 }
 
@@ -2510,6 +2556,54 @@ impl<T: Config> Module<T> {
         Self::deposit_event(RawEvent::RemovePreApprovedAsset(caller_did, ticker));
         Ok(())
     }
+
+    /// Sets all identities in the `mediators` set as mandatory mediators for any instruction transfering `ticker`.
+    fn base_add_mandatory_mediators(
+        origin: T::RuntimeOrigin,
+        ticker: Ticker,
+        new_mediators: BoundedBTreeSet<IdentityId, T::MaxAssetMediators>,
+    ) -> DispatchResult {
+        // Verifies if the caller has the correct permissions for this asset
+        let caller_did = <ExternalAgents<T>>::ensure_perms(origin, ticker)?;
+        // Tries to add all new identities as mandatory mediators for the asset
+        MandatoryMediators::<T>::try_mutate(ticker, |mandatory_mediators| -> DispatchResult {
+            for new_mediator in &new_mediators {
+                mandatory_mediators
+                    .try_insert(*new_mediator)
+                    .map_err(|_| Error::<T>::NumberOfAssetMediatorsExceeded)?;
+            }
+            Ok(())
+        })?;
+
+        Self::deposit_event(RawEvent::AssetMediatorsAdded(
+            caller_did,
+            ticker,
+            new_mediators.into_inner(),
+        ));
+        Ok(())
+    }
+
+    /// Removes all identities in the `mediators` set from the mandatory mediators list for the given `ticker`.
+    fn base_remove_mandatory_mediators(
+        origin: T::RuntimeOrigin,
+        ticker: Ticker,
+        mediators: BoundedBTreeSet<IdentityId, T::MaxAssetMediators>,
+    ) -> DispatchResult {
+        // Verifies if the caller has the correct permissions for this asset
+        let caller_did = <ExternalAgents<T>>::ensure_perms(origin, ticker)?;
+        // Removes the identities from the mandatory mediators list
+        MandatoryMediators::<T>::mutate(ticker, |mandatory_mediators| {
+            for mediator in &mediators {
+                mandatory_mediators.remove(mediator);
+            }
+        });
+        Self::deposit_event(RawEvent::AssetMediatorsRemoved(
+            caller_did,
+            ticker,
+            mediators.into_inner(),
+        ));
+        Ok(())
+    }
 }
 
 impl<T: Config> AssetFnTrait<T::AccountId, T::RuntimeOrigin> for Module<T> {
@@ -2578,4 +2672,13 @@ impl<T: Config> AssetFnTrait<T::AccountId, T::RuntimeOrigin> for Module<T> {
             None => Self::register_asset_metadata_global_type(origin, name, spec),
         }
     }
+
+    #[cfg(feature = "runtime-benchmarks")]
+    fn add_mandatory_mediators(
+        origin: T::RuntimeOrigin,
+        ticker: Ticker,
+        mediators: BTreeSet<IdentityId>,
+    ) -> DispatchResult {
+        Self::add_mandatory_mediators(origin, ticker, mediators.try_into().unwrap_or_default())
+    }
 }

pallets/common/src/traits/asset.rs

@@ -17,6 +17,7 @@ use frame_support::decl_event;
 use frame_support::dispatch::DispatchResult;
 use frame_support::traits::{Currency, Get, UnixTime};
 use frame_support::weights::Weight;
+use sp_std::collections::btree_set::BTreeSet;
 use sp_std::prelude::Vec;
 
 use polymesh_primitives::asset::{AssetName, AssetType, CustomAssetTypeId, FundingRoundName};
@@ -70,9 +71,13 @@ pub trait Config:
     type AssetFn: AssetFnTrait<Self::AccountId, Self::RuntimeOrigin>;
 
     type WeightInfo: WeightInfo;
+
     type CPWeightInfo: crate::traits::checkpoint::WeightInfo;
 
     type NFTFn: NFTTrait<Self::RuntimeOrigin>;
+
+    /// Maximum number of mediators for an asset.
+    type MaxAssetMediators: Get<u32>;
 }
 
 decl_event! {
@@ -177,6 +182,12 @@ decl_event! {
         /// An identity has removed an asset to the list of pre aprroved receivement.
         /// Parameters: [`IdentityId`] of caller, [`Ticker`] of the asset.
         RemovePreApprovedAsset(IdentityId, Ticker),
+        /// An identity has added mandatory mediators to an asset.
+        /// Parameters: [`IdentityId`] of caller, [`Ticker`] of the asset, the identity of all mediators added.
+        AssetMediatorsAdded(IdentityId, Ticker, BTreeSet<IdentityId>),
+        /// An identity has removed mediators from an asset.
+        /// Parameters: [`IdentityId`] of caller, [`Ticker`] of the asset, the identity of all mediators removed.
+        AssetMediatorsRemoved(IdentityId, Ticker, BTreeSet<IdentityId>)
     }
 }
 
@@ -211,6 +222,8 @@ pub trait WeightInfo {
     fn remove_ticker_affirmation_exemption() -> Weight;
     fn pre_approve_ticker() -> Weight;
     fn remove_ticker_pre_approval() -> Weight;
+    fn add_mandatory_mediators(n: u32) -> Weight;
+    fn remove_mandatory_mediators(n: u32) -> Weight;
 }
 
 pub trait AssetFnTrait<Account, Origin> {
@@ -252,4 +265,11 @@ pub trait AssetFnTrait<Account, Origin> {
         name: AssetMetadataName,
         spec: AssetMetadataSpec,
     ) -> DispatchResult;
+
+    #[cfg(feature = "runtime-benchmarks")]
+    fn add_mandatory_mediators(
+        origin: Origin,
+        ticker: Ticker,
+        mediators: BTreeSet<IdentityId>,
+    ) -> DispatchResult;
 }

pallets/common/src/traits/settlement.rs

@@ -77,6 +77,12 @@ decl_event!(
         /// An instruction has been automatically affirmed.
         /// Parameters: [`IdentityId`] of the caller, [`PortfolioId`] of the receiver, and [`InstructionId`] of the instruction.
         InstructionAutomaticallyAffirmed(IdentityId, PortfolioId, InstructionId),
+        /// An instruction has affirmed by a mediator.
+        /// Parameters: [`IdentityId`] of the mediator and [`InstructionId`] of the instruction.
+        MediatorAffirmationReceived(IdentityId, InstructionId),
+        /// An instruction affirmation has been withdrawn by a mediator.
+        /// Parameters: [`IdentityId`] of the mediator and [`InstructionId`] of the instruction.
+        MediatorAffirmationWithdrawn(IdentityId, InstructionId),
     }
 );
 
@@ -101,7 +107,20 @@ pub trait WeightInfo {
     fn affirm_with_receipts_rcv(f: u32, n: u32, o: u32) -> Weight;
     fn affirm_instruction_rcv(f: u32, n: u32) -> Weight;
     fn withdraw_affirmation_rcv(f: u32, n: u32, o: u32) -> Weight;
+    fn add_instruction_with_mediators(f: u32, n: u32, o: u32, m: u32) -> Weight;
+    fn add_and_affirm_with_mediators(f: u32, n: u32, o: u32, m: u32) -> Weight;
+    fn affirm_instruction_as_mediator() -> Weight;
+    fn withdraw_affirmation_as_mediator() -> Weight;
+    fn reject_instruction_as_mediator(f: u32, n: u32, o: u32) -> Weight;
 
+    fn add_and_affirm_with_mediators_legs(legs: &[Leg], n_mediators: u32) -> Weight {
+        let (f, n, o) = Self::get_transfer_by_asset(legs);
+        Self::add_and_affirm_with_mediators(f, n, o, n_mediators)
+    }
+    fn add_instruction_with_mediators_legs(legs: &[Leg], n_mediators: u32) -> Weight {
+        let (f, n, o) = Self::get_transfer_by_asset(legs);
+        Self::add_instruction_with_mediators(f, n, o, n_mediators)
+    }
     fn add_instruction_legs(legs: &[Leg]) -> Weight {
         let (f, n, o) = Self::get_transfer_by_asset(legs);
         Self::add_instruction(f, n, o)
@@ -209,14 +228,29 @@ pub trait WeightInfo {
             None => Self::withdraw_affirmation(10, 100, 10),
         }
     }
-    fn reject_instruction_input(asset_count: Option<AssetCount>) -> Weight {
+    fn reject_instruction_input(asset_count: Option<AssetCount>, as_mediator: bool) -> Weight {
         match asset_count {
-            Some(asset_count) => Self::reject_instruction(
-                asset_count.fungible(),
-                asset_count.non_fungible(),
-                asset_count.off_chain(),
-            ),
-            None => Self::reject_instruction(10, 100, 10),
+            Some(asset_count) => {
+                if as_mediator {
+                    return Self::reject_instruction_as_mediator(
+                        asset_count.fungible(),
+                        asset_count.non_fungible(),
+                        asset_count.off_chain(),
+                    );
+                }
+                Self::reject_instruction(
+                    asset_count.fungible(),
+                    asset_count.non_fungible(),
+                    asset_count.off_chain(),
+                )
+            }
+            None => {
+                let (f, n, o) = (10, 100, 10);
+                if as_mediator {
+                    return Self::reject_instruction_as_mediator(f, n, o);
+                }
+                Self::reject_instruction(f, n, o)
+            }
         }
     }
 }