Interface IActionRenderer
Listens state changes of every step of actions, besides blocks, on a BlockChain. If you need more fine-grained events than IRenderer, implement this interface instead.
The invocation order of methods for each Block are:
- RenderBlock(Block, Block) (one time)
- RenderAction(IValue, IActionContext, IAccountStateDelta) & RenderActionError(IValue, IActionContext, Exception) (zero or more times)
- RenderBlockEnd(Block, Block) (one time)
Inherited Members
Namespace: Libplanet.Blockchain.Renderers
Assembly: Libplanet.dll
Syntax
public interface IActionRenderer : IRenderer
Remarks
Although Transactions affect the states in the IStateStore all or nothing at all (i.e., atomically), IActionRenderer receives all action-related events (RenderAction(IValue, IActionContext, IAccountStateDelta)/RenderActionError(IValue, IActionContext, Exception)) immediately without buffering, which means actions are rendered even before whether there are any actions throwing an exception in the same transaction is determined. In other words, for IActionRenderers, it is not guaranteed that actions in a transaction are atomic.
If your action renderer expects to receive only render events about actions belonging successful transactions, wrap your action renderer with AtomicActionRenderer.
Methods
| Improve this Doc View SourceRenderAction(IValue, IActionContext, IAccountStateDelta)
Does things that should be done right after an action
is executed and applied to the blockchain.
Declaration
void RenderAction(IValue action, IActionContext context, IAccountStateDelta nextStates)
Parameters
Type | Name | Description |
---|---|---|
Bencodex.Types.IValue | action | An executed action. |
IActionContext | context | The equivalent context object to an object passed to
the |
IAccountStateDelta | nextStates | The states right after this action executed,
which means it is equivalent to the states |
Remarks
It is guaranteed to be called only once for an action
,
and only after applied to the blockchain, unless an exception is thrown during executing
the action
(in that case RenderActionError(IValue, IActionContext, Exception) is called instead) or
once the action
has been unrendered.
Also note that this method is invoked after RenderBlock(Block, Block) method is called
(where its second parameter newTip
contains a transaction the action
belongs to).
RenderActionError(IValue, IActionContext, Exception)
Does the similar things to RenderAction(IValue, IActionContext, IAccountStateDelta), except that this method
is invoked when action
has terminated with an exception.
Declaration
void RenderActionError(IValue action, IActionContext context, Exception exception)
Parameters
Type | Name | Description |
---|---|---|
Bencodex.Types.IValue | action | An action which threw an exception during execution. |
IActionContext | context | The equivalent context object to an object passed to
the |
Exception | exception | The exception thrown during executing the |
Remarks
Also note that this method is invoked after RenderBlock(Block, Block) method is called
(where its second parameter newTip
contains a transaction the action
belongs to).
RenderBlockEnd(Block, Block)
Does things that should be done right all actions in a new Block are rendered.
Declaration
void RenderBlockEnd(Block oldTip, Block newTip)
Parameters
Type | Name | Description |
---|---|---|
Block | oldTip | The previous Tip. |
Block | newTip | The current Tip. |
Remarks
It is guaranteed to be called only once for a block.