Substrate中assets模块

一个处理可分割资产的简单、安全的模块。这个模块太简单，可以深入看看generic-asset模块。

Trait

/// The overarching event type.
type Event: From<Event<Self>> + Into<<Self as system::Trait>::Event>;

/// 余额记录
type Balance: Member + Parameter + SimpleArithmetic + Default + Copy;

/// 资产identifier
type AssetId: Parameter + SimpleArithmetic + Default + Copy;

Storage

/// 账号余额记录
Balances: map (T::AssetId, T::AccountId) => T::Balance;
/// 下一个资产identifier
NextAssetId get(fn next_asset_id): T::AssetId;
/// 某个资产的总发行量
TotalSupply: map T::AssetId => T::Balance;

Module

• fn issue(origin,#[compact] total: T::Balance)
  • 发行资产
• fn transfer(origin,#[compact] id: T::AssetId,target: <T::Lookup as StaticLookup>::Source, #[compact] amount: T::Balance)
  • 转账
• fn destroy(origin, #[compact] id: T::AssetId)
  • 销毁资产
• pub fn balance(id: T::AssetId, who: T::AccountId) -> T::Balance
  • 查询某个用户某个资产的余额
• pub fn total_supply(id: T::AssetId) -> T::Balance
  • 获取某个资产的发行总量

Event

decl_event!(
    pub enum Event<T>
        where <T as system::Trait>::AccountId,
              <T as Trait>::Balance,
              <T as Trait>::AssetId {
        /// Some assets were issued.
        Issued(AssetId, AccountId, Balance),
        /// Some assets were transferred.
        Transferred(AssetId, AccountId, AccountId, Balance),
        /// Some assets were destroyed.
        Destroyed(AssetId, AccountId, Balance),
    }
);