difftreelog
chore fixed code review request
in: master
1 file changed
pallets/structure/src/lib.rsdiffbeforeafterboth1// Copyright 2019-2022 Unique Network (Gibraltar) Ltd.2// This file is part of Unique Network.34// Unique Network is free software: you can redistribute it and/or modify5// it under the terms of the GNU General Public License as published by6// the Free Software Foundation, either version 3 of the License, or7// (at your option) any later version.89// Unique Network is distributed in the hope that it will be useful,10// but WITHOUT ANY WARRANTY; without even the implied warranty of11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the12// GNU General Public License for more details.1314// You should have received a copy of the GNU General Public License15// along with Unique Network. If not, see <http://www.gnu.org/licenses/>.1617//! # Structure Pallet18//!19//! The Structure pallet provides functionality for handling tokens nesting an unnesting.20//!21//! - [`Config`]22//! - [`Pallet`]23//!24//! ## Overview25//!26//! The Structure pallet provides functions for:27//!28//! - Searching for token parents, children and owners. Actual implementation of searching for29//! parent/child is done by pallets corresponding to token's collection type.30//! - Nesting and unnesting tokens. Actual implementation of nesting is done by pallets corresponding31//! to token's collection type.32//!33//! ### Terminology34//!35//! - **Nesting:** Setting up parent-child relationship between tokens. Nested tokens are inhereting36//! owner from their parent. There could be multiple levels of nesting. Token couldn't be nested in37//! it's child token i.e. parent-child relationship graph shouldn't have38//!39//! - **Parent:** Token that current token is nested in.40//!41//! - **Owner:** Account that owns the token and all nested tokens.42//!43//! ## Interface44//!45//! ### Available Functions46//!47//! - `find_parent` - Find parent of the token. It could be an account or another token.48//! - `parent_chain` - Find chain of parents of the token.49//! - `find_topmost_owner` - Find account or token in the end of the chain of parents.50//! - `check_nesting` - Check if the token could be nested in the other token51//! - `nest_if_sent_to_token` - Nest the token in the other token52//! - `unnest_if_nested` - Unnest the token from the other token5354#![cfg_attr(not(feature = "std"), no_std)]5556use pallet_common::CommonCollectionOperations;57use sp_std::collections::btree_set::BTreeSet;5859use frame_support::dispatch::{DispatchError, DispatchResult, DispatchResultWithPostInfo};60use frame_support::fail;61pub use pallet::*;62use pallet_common::{dispatch::CollectionDispatch, CollectionHandle};63use up_data_structs::{CollectionId, TokenId, mapping::TokenAddressMapping, budget::Budget};6465#[cfg(feature = "runtime-benchmarks")]66pub mod benchmarking;67pub mod weights;6869pub type SelfWeightOf<T> = <T as crate::Config>::WeightInfo;7071#[frame_support::pallet]72pub mod pallet {73 use frame_support::Parameter;74 use frame_support::dispatch::{GetDispatchInfo, UnfilteredDispatchable};75 use frame_support::pallet_prelude::*;7677 use super::*;7879 #[pallet::error]80 pub enum Error<T> {81 /// While searched for owner, got already checked account82 OuroborosDetected,83 /// While searched for owner, encountered depth limit84 DepthLimit,85 /// While iterating over children, encountered breadth limit86 BreadthLimit,87 /// While searched for owner, found token owner by not-yet-existing token88 TokenNotFound,89 }9091 #[pallet::event]92 pub enum Event<T> {93 /// Executed call on behalf of token94 Executed(DispatchResult),95 }9697 #[pallet::config]98 pub trait Config: frame_system::Config + pallet_common::Config {99 type WeightInfo: weights::WeightInfo;100 type Event: IsType<<Self as frame_system::Config>::Event> + From<Event<Self>>;101 type Call: Parameter + UnfilteredDispatchable<Origin = Self::Origin> + GetDispatchInfo;102 }103104 #[pallet::pallet]105 pub struct Pallet<T>(_);106107 #[pallet::call]108 impl<T: Config> Pallet<T> {109 // #[pallet::weight({110 // let dispatch_info = call.get_dispatch_info();111112 // (113 // dispatch_info.weight114 // // Cost of dereferencing parent115 // .saturating_add(T::DbWeight::get().reads(2 * *max_depth as Weight))116 // .saturating_add(4000 * *max_depth as Weight),117 // dispatch_info.class)118 // })]119 // pub fn execute(120 // origin: OriginFor<T>,121 // call: Box<<T as Config>::Call>,122 // max_depth: u32,123 // ) -> DispatchResult {124 }125}126127#[derive(PartialEq)]128pub enum Parent<CrossAccountId> {129 /// Token owned by normal account130 User(CrossAccountId),131 /// Passed token not found132 TokenNotFound,133 /// Token owner is another token (target token still may not exist)134 Token(CollectionId, TokenId),135}136137impl<T: Config> Pallet<T> {138 /// Find account owning the `token` or a token that the `token` is nested in.139 ///140 /// Returns the enum that have three variants:141 /// - [`User`](crate::Parent<T>::User): Contains account.142 /// - [`Token`](crate::Parent<T>::Token): Contains token id and collection id.143 /// - [`TokenNotFound`](crate::Parent<T>::TokenNotFound): Indicates that parent was not found144 pub fn find_parent(145 collection: CollectionId,146 token: TokenId,147 ) -> Result<Parent<T::CrossAccountId>, DispatchError> {148 // TODO: Reduce cost by not reading collection config149 let handle = match CollectionHandle::try_get(collection) {150 Ok(v) => v,151 Err(_) => return Ok(Parent::TokenNotFound),152 };153 let handle = T::CollectionDispatch::dispatch(handle);154 let handle = handle.as_dyn();155156 Ok(match handle.token_owner(token) {157 Some(owner) => match T::CrossTokenAddressMapping::address_to_token(&owner) {158 Some((collection, token)) => Parent::Token(collection, token),159 None => Parent::User(owner),160 },161 None => Parent::TokenNotFound,162 })163 }164165 /// Find chain of parents of current token166 ///167 /// Returns the parent of the current token, than the parent of the parent and so on until token without a parent168 /// is returned. Returns error if cycle is detected.169 pub fn parent_chain(170 mut collection: CollectionId,171 mut token: TokenId,172 ) -> impl Iterator<Item = Result<Parent<T::CrossAccountId>, DispatchError>> {173 let mut finished = false;174 let mut visited = BTreeSet::new();175 visited.insert((collection, token));176 core::iter::from_fn(move || {177 if finished {178 return None;179 }180 let parent = Self::find_parent(collection, token);181 match parent {182 Ok(Parent::Token(new_collection, new_token)) => {183 collection = new_collection;184 token = new_token;185 if !visited.insert((new_collection, new_token)) {186 finished = true;187 return Some(Err(<Error<T>>::OuroborosDetected.into()));188 }189 }190 _ => finished = true,191 }192 Some(parent as Result<_, DispatchError>)193 })194 }195196 /// Try to dereference address, until finding top level owner197 ///198 /// May return token address if parent token not yet exists199 ///200 /// - `budget`: Limit for searching parents in depth.201 pub fn find_topmost_owner(202 collection: CollectionId,203 token: TokenId,204 budget: &dyn Budget,205 ) -> Result<T::CrossAccountId, DispatchError> {206 let owner = Self::parent_chain(collection, token)207 .take_while(|_| budget.consume())208 .find(|p| matches!(p, Ok(Parent::User(_) | Parent::TokenNotFound)))209 .ok_or(<Error<T>>::DepthLimit)??;210211 Ok(match owner {212 Parent::User(v) => v,213 _ => fail!(<Error<T>>::TokenNotFound),214 })215 }216217 /// Find the topmost parent and check that assigning `for_nest` token as a child for218 /// `token` wouldn't create a cycle.219 ///220 /// - `budget`: Limit for searching parents in depth.221 pub fn get_checked_topmost_owner(222 collection: CollectionId,223 token: TokenId,224 for_nest: Option<(CollectionId, TokenId)>,225 budget: &dyn Budget,226 ) -> Result<T::CrossAccountId, DispatchError> {227 // Tried to nest token in itself228 if Some((collection, token)) == for_nest {229 return Err(<Error<T>>::OuroborosDetected.into());230 }231232 for parent in Self::parent_chain(collection, token).take_while(|_| budget.consume()) {233 match parent? {234 // Tried to nest token in chain, which has this token as one of parents235 Parent::Token(collection, token) if Some((collection, token)) == for_nest => {236 return Err(<Error<T>>::OuroborosDetected.into())237 }238 // Token is owned by other user239 Parent::User(user) => return Ok(user),240 Parent::TokenNotFound => return Err(<Error<T>>::TokenNotFound.into()),241 // Continue parent chain242 Parent::Token(_, _) => {}243 }244 }245246 Err(<Error<T>>::DepthLimit.into())247 }248249 /// Burn token and all of it's nested tokens250 ///251 /// - `self_budget`: Limit for searching children in depth.252 /// - `breadth_budget`: Limit of breadth of searching children.253 pub fn burn_item_recursively(254 from: T::CrossAccountId,255 collection: CollectionId,256 token: TokenId,257 self_budget: &dyn Budget,258 breadth_budget: &dyn Budget,259 ) -> DispatchResultWithPostInfo {260 let handle = <CollectionHandle<T>>::try_get(collection)?;261 let dispatch = T::CollectionDispatch::dispatch(handle);262 let dispatch = dispatch.as_dyn();263 dispatch.burn_item_recursively(from.clone(), token, self_budget, breadth_budget)264 }265266 /// Check if `token` indirectly owned by `user`267 ///268 /// Returns `true` if `user` is `token`'s owner. Or If token is provided as `user` then269 /// check that `user` and `token` have same owner.270 /// Checks that assigning `for_nest` token as a child for `token` wouldn't create a cycle.271 ///272 /// - `budget`: Limit for searching parents in depth.273 pub fn check_indirectly_owned(274 user: T::CrossAccountId,275 collection: CollectionId,276 token: TokenId,277 for_nest: Option<(CollectionId, TokenId)>,278 budget: &dyn Budget,279 ) -> Result<bool, DispatchError> {280 let target_parent = match T::CrossTokenAddressMapping::address_to_token(&user) {281 Some((collection, token)) => Self::find_topmost_owner(collection, token, budget)?,282 None => user,283 };284285 Self::get_checked_topmost_owner(collection, token, for_nest, budget)286 .map(|indirect_owner| indirect_owner == target_parent)287 }288289 /// Checks that `under` is valid token and that `token_id` could be nested under it290 /// and that `from` is `under`'s owner291 ///292 /// Returns OK if `under` is not a token293 ///294 /// - `nesting_budget`: Limit for searching parents in depth.295 pub fn check_nesting(296 from: T::CrossAccountId,297 under: &T::CrossAccountId,298 collection_id: CollectionId,299 token_id: TokenId,300 nesting_budget: &dyn Budget,301 ) -> DispatchResult {302 Self::try_exec_if_owner_is_valid_nft(under, |collection, parent_id| {303 collection.check_nesting(from, (collection_id, token_id), parent_id, nesting_budget)304 })305 }306307 /// Nests `token_id` under `under` token308 ///309 /// Returns OK if `under` is not a token. Checks that nesting is possible.310 ///311 /// - `nesting_budget`: Limit for searching parents in depth.312 pub fn nest_if_sent_to_token(313 from: T::CrossAccountId,314 under: &T::CrossAccountId,315 collection_id: CollectionId,316 token_id: TokenId,317 nesting_budget: &dyn Budget,318 ) -> DispatchResult {319 Self::try_exec_if_owner_is_valid_nft(under, |collection, parent_id| {320 collection.check_nesting(from, (collection_id, token_id), parent_id, nesting_budget)?;321322 collection.nest(parent_id, (collection_id, token_id));323324 Ok(())325 })326 }327328 /// Nests `token_id` under `owner` token329 ///330 /// Caller should check that nesting wouldn't cause recursion in nesting331 pub fn nest_if_sent_to_token_unchecked(332 owner: &T::CrossAccountId,333 collection_id: CollectionId,334 token_id: TokenId,335 ) {336 Self::exec_if_owner_is_valid_nft(owner, |collection, parent_id| {337 collection.nest(parent_id, (collection_id, token_id))338 });339 }340341 /// Unnests `token_id` from `owner`.342 pub fn unnest_if_nested(343 owner: &T::CrossAccountId,344 collection_id: CollectionId,345 token_id: TokenId,346 ) {347 Self::exec_if_owner_is_valid_nft(owner, |collection, parent_id| {348 collection.unnest(parent_id, (collection_id, token_id))349 });350 }351352 fn exec_if_owner_is_valid_nft(353 account: &T::CrossAccountId,354 action: impl FnOnce(&dyn CommonCollectionOperations<T>, TokenId),355 ) {356 Self::try_exec_if_owner_is_valid_nft(account, |collection, id| {357 action(collection, id);358 Ok(())359 })360 .unwrap();361 }362363 fn try_exec_if_owner_is_valid_nft(364 account: &T::CrossAccountId,365 action: impl FnOnce(&dyn CommonCollectionOperations<T>, TokenId) -> DispatchResult,366 ) -> DispatchResult {367 let account = T::CrossTokenAddressMapping::address_to_token(account);368369 if account.is_none() {370 return Ok(());371 }372373 let account = account.unwrap();374375 let handle = <CollectionHandle<T>>::try_get(account.0);376377 if handle.is_err() {378 return Ok(());379 }380381 let handle = handle.unwrap();382383 let dispatch = T::CollectionDispatch::dispatch(handle);384 let dispatch = dispatch.as_dyn();385386 action(dispatch, account.1)387 }388}