frame/executive解剖

类型定义

pub type CheckedOf<E, C> = <E as Checkable<C>>::Checked;
pub type CallOf<E, C> = <CheckedOf<E, C> as Applyable>::Call;
pub type OriginOf<E, C> = <CallOf<E, C> as Dispatchable>::Origin;

特殊结构体定义(PhantomData)

/// Main entry point for certain runtime actions as e.g. `execute_block`.
///
/// Generic parameters:
/// - `System`: Something that implements `frame_system::Config`
/// - `Block`: The block type of the runtime
/// - `Context`: The context that is used when checking an extrinsic.
/// - `UnsignedValidator`: The unsigned transaction validator of the runtime.
/// - `AllPalletsWithSystem`: Tuple that contains all pallets including frame system pallet. Will be
///   used to call hooks e.g. `on_initialize`.
/// - `OnRuntimeUpgrade`: Custom logic that should be called after a runtime upgrade. Modules are
///   already called by `AllPalletsWithSystem`. It will be called before all modules will be called.
pub struct Executive<
	System,
	Block,
	Context,
	UnsignedValidator,
	AllPalletsWithSystem,
	OnRuntimeUpgrade = (),
>(
	PhantomData<(
		System,
		Block,
		Context,
		UnsignedValidator,
		AllPalletsWithSystem,
		OnRuntimeUpgrade,
	)>,
);

定义并实现许多方法

substrate/frame/executive/src/lib.rs

			AllPalletsWithSystem,
			COnRuntimeUpgrade,
		>::execute_block(block);
	}
}

impl<
		System: frame_system::Config + EnsureInherentsAreFirst<Block>,
		Block: traits::Block<Header = System::Header, Hash = System::Hash>,
		Context: Default,
		UnsignedValidator,
		AllPalletsWithSystem: OnRuntimeUpgrade
			+ OnInitialize<System::BlockNumber>
			+ OnIdle<System::BlockNumber>
			+ OnFinalize<System::BlockNumber>
			+ OffchainWorker<System::BlockNumber>,
		COnRuntimeUpgrade: OnRuntimeUpgrade,
	> Executive<System, Block, Context, UnsignedValidator, AllPalletsWithSystem, COnRuntimeUpgrade>
where
	Block::Extrinsic: Checkable<Context> + Codec,

实现trait中定义的方法

substrate/frame/executive/src/lib.rs

  1. 下列trait限定的意思：
    1. 为Executive结构体实现ExecuteBlock这个trait的方法
    2. for Executive<…>：Executive本身是个结构体，用到了这些类型
    3. impl<…>：这些类型分别有哪些trait限定，要用到关联类型限定的，就放在where子句中
    4. where子句：主要先约束好关联类型Block::Extrinsic，给后面的使用
    5. 总结impl与where子句：这里将简单情况放在impl中，将复杂的关联类型限定放在where子句中。
  2. 关于CheckedOf、CallOf、OriginOf这三个：
    1. impl中的UnsignedValidator用到CallOf， CallOf用到CheckedOf
    2. (问题)OriginOf的用途
impl<
		System: frame_system::Config + EnsureInherentsAreFirst<Block>,
		Block: traits::Block<Header = System::Header, Hash = System::Hash>,
		Context: Default,
		UnsignedValidator,
		AllPalletsWithSystem: OnRuntimeUpgrade
			+ OnInitialize<System::BlockNumber>
			+ OnIdle<System::BlockNumber>
			+ OnFinalize<System::BlockNumber>
			+ OffchainWorker<System::BlockNumber>,
		COnRuntimeUpgrade: OnRuntimeUpgrade,
	> ExecuteBlock<Block>
	for Executive<System, Block, Context, UnsignedValidator, AllPalletsWithSystem, COnRuntimeUpgrade>
// where
//	  Block::Extrinsic: Checkable<Context> + Codec,
//	  <Block::Extrinsic as Checkable<Context>>::Checked: Applyable + GetDispatchInfo,
//	  <Block::Extrinsic as Checkable<Context>>::Checked as Applyable>::Call: Dispatchable<Info = DispatchInfo, PostInfo = PostDispatchInfo>,
//	  <Block::Extrinsic as Checkable<Context>>::Checked as Applyable>::Call: From<Option<System::AccountId>>,
//	  UnsignedValidator: ValidateUnsigned<Call = <Block::Extrinsic as Checkable<Context>>::Checked as Applyable>::Call>,
where
	Block::Extrinsic: Checkable<Context> + Codec,
	CheckedOf<Block::Extrinsic, Context>: Applyable + GetDispatchInfo,
	CallOf<Block::Extrinsic, Context>:
		Dispatchable<Info = DispatchInfo, PostInfo = PostDispatchInfo>,
	OriginOf<Block::Extrinsic, Context>: From<Option<System::AccountId>>,
	UnsignedValidator: ValidateUnsigned<Call = CallOf<Block::Extrinsic, Context>>,
{
	fn execute_block(block: Block) {
		Executive::<
			System,
			Block,
			Context,