Class BlockPolicy<T>

A default implementation of IBlockPolicy<T> interface.

Inheritance

Object

BlockPolicy<T>

Implements

IBlockPolicy<T>

Inherited Members

Object.Equals(Object)

Object.Equals(Object, Object)

Object.GetHashCode()

Object.GetType()

Object.MemberwiseClone()

Object.ReferenceEquals(Object, Object)

Object.ToString()

Namespace: Libplanet.Blockchain.Policies

Assembly: Libplanet.dll

Syntax

public class BlockPolicy<T> : IBlockPolicy<T> where T : IAction, new()

Type Parameters

Name	Description
T	An IAction type. It should match to Block<T>'s type parameter.

Constructors

BlockPolicy(IAction, Int32, Int64, Int32, Int32, Int32, Int32, Func<Transaction<T>, BlockChain<T>, Boolean>, IComparer<BlockPerception>)

Creates a BlockPolicy<T> with configuring BlockInterval in milliseconds, Libplanet.Blockchain.Policies.BlockPolicy`1.MinimumDifficulty and Libplanet.Blockchain.Policies.BlockPolicy`1.DifficultyBoundDivisor.

Declaration

public BlockPolicy(IAction blockAction = null, int blockIntervalMilliseconds = 5000, long minimumDifficulty = 1024L, int difficultyBoundDivisor = 128, int maxTransactionsPerBlock = 100, int maxBlockBytes = 102400, int maxGenesisBytes = 1048576, Func<Transaction<T>, BlockChain<T>, bool> doesTransactionFollowPolicy = null, IComparer<BlockPerception> canonicalChainComparer = null)

Parameters

Type	Name	Description
IAction	blockAction	A block action to execute and be rendered for every block.
Int32	blockIntervalMilliseconds	Configures BlockInterval in milliseconds. 5000 milliseconds by default.
Int64	minimumDifficulty	Configures Libplanet.Blockchain.Policies.BlockPolicy`1.MinimumDifficulty. 1024 by default.
Int32	difficultyBoundDivisor	Configures Libplanet.Blockchain.Policies.BlockPolicy`1.DifficultyBoundDivisor. 128 by default.
Int32	maxTransactionsPerBlock	Configures MaxTransactionsPerBlock. 100 by default.
Int32	maxBlockBytes	Configures GetMaxBlockBytes(Int64) where the block is not a genesis. 100 KiB by default.
Int32	maxGenesisBytes	Configures GetMaxBlockBytes(Int64) where the block is a genesis. 1 MiB by default.
Func<Transaction<T>, BlockChain<T>, Boolean>	doesTransactionFollowPolicy	A predicate that determines if the transaction follows the block policy.
IComparer<BlockPerception>	canonicalChainComparer	The custom rule to determine which is the canonical chain. If omitted, TotalDifficultyComparer is used by default.

BlockPolicy(IAction, TimeSpan, Int64, Int32, Int32, Int32, Int32, Func<Transaction<T>, BlockChain<T>, Boolean>, IComparer<BlockPerception>)

Creates a BlockPolicy<T> with configuring BlockInterval, Libplanet.Blockchain.Policies.BlockPolicy`1.MinimumDifficulty and Libplanet.Blockchain.Policies.BlockPolicy`1.DifficultyBoundDivisor.

Declaration

public BlockPolicy(IAction blockAction, TimeSpan blockInterval, long minimumDifficulty, int difficultyBoundDivisor, int maxTransactionsPerBlock, int maxBlockBytes, int maxGenesisBytes, Func<Transaction<T>, BlockChain<T>, bool> doesTransactionFollowPolicy = null, IComparer<BlockPerception> canonicalChainComparer = null)

Parameters

Type	Name	Description
IAction	blockAction	A block action to execute and be rendered for every block.
TimeSpan	blockInterval	Configures BlockInterval.
Int64	minimumDifficulty	Configures Libplanet.Blockchain.Policies.BlockPolicy`1.MinimumDifficulty.
Int32	difficultyBoundDivisor	Configures Libplanet.Blockchain.Policies.BlockPolicy`1.DifficultyBoundDivisor.
Int32	maxTransactionsPerBlock	Configures MaxTransactionsPerBlock.
Int32	maxBlockBytes	Configures GetMaxBlockBytes(Int64) where the block is not a genesis.
Int32	maxGenesisBytes	Configures GetMaxBlockBytes(Int64) where the block is a genesis.
Func<Transaction<T>, BlockChain<T>, Boolean>	doesTransactionFollowPolicy	A predicate that determines if the transaction follows the block policy.
IComparer<BlockPerception>	canonicalChainComparer	The custom rule to determine which is the canonical chain. If omitted, TotalDifficultyComparer (having OutdateAfter configured to triple of blockInterval) is used by default.

Properties

BlockAction

A block action to execute and be rendered for every block.

Declaration

public IAction BlockAction { get; }

Property Value

Type	Description
IAction

BlockInterval

An appropriate interval between consecutive Block<T>s. It is usually from 20 to 30 seconds.

If a previous interval took longer than this GetNextBlockDifficulty(BlockChain<T>) method raises the Difficulty. If it took shorter than this Difficulty is dropped.

Declaration

public TimeSpan BlockInterval { get; }

Property Value

Type	Description
TimeSpan

CanonicalChainComparer

A comparer to determine which branch is the canonical chain (i.e., best chain). The most greater one according to this comparer is considered to be the canon.

Declaration

public IComparer<BlockPerception> CanonicalChainComparer { get; }

Property Value

Type	Description
IComparer<BlockPerception>

See Also

IBlockExcerpt

TotalDifficultyComparer

MaxTransactionsPerBlock

The maximum number of Transactions that a Block<T> can accept. This value must not be negative and must be deterministic (i.e., must not change after an object is once instantiated).

Declaration

public int MaxTransactionsPerBlock { get; }

Property Value

Type	Description
Int32

Remarks

If the value is less then 1, it's treated as 1.

Methods

DoesTransactionFollowsPolicy(Transaction<T>, BlockChain<T>)

A predicate that determines if the transaction follows the block policy.

Declaration

public virtual bool DoesTransactionFollowsPolicy(Transaction<T> transaction, BlockChain<T> blockChain)

Parameters

Type	Name	Description
Transaction<T>	transaction	A Transaction<T> to determine.
BlockChain<T>	blockChain	A BlockChain<T> for given transaction.

Returns

Type	Description
Boolean	true if transactionis valid; otherwise, false.

GetMaxBlockBytes(Int64)

Gets the maximum length of a Block<T> in bytes. It can vary depending on a given index, but should be deterministic; for the same index, the same value must be returned.

Declaration

public int GetMaxBlockBytes(long index)

Parameters

Type	Name	Description
Int64	index	An Index of a block to mine or receive.

Returns

Type	Description
Int32	The maximum length of a Block<T> in bytes to accept.

Remarks

If it returns less then 1, it is treated as 1, because there is no block taking 0 bytes or negative length of bytes.

GetNextBlockDifficulty(BlockChain<T>)

Determines a right Difficulty for a new Block<T> to be mined right after the given blocks.

Declaration

public virtual long GetNextBlockDifficulty(BlockChain<T> blocks)

Parameters

Type	Name	Description
BlockChain<T>	blocks	Consecutive Block<T>s to be followed by a new Block<T> to be mined.

Returns

Type	Description
Int64	A right Difficulty for a new Block<T> to be mined.

ValidateNextBlock(BlockChain<T>, Block<T>)

Checks if nextBlock is invalid, and if that returns the reason.

Note that it returns null when nextBlock is valid.

Declaration

public virtual InvalidBlockException ValidateNextBlock(BlockChain<T> blocks, Block<T> nextBlock)

Parameters

Type	Name	Description
BlockChain<T>	blocks	Consecutive Block<T>s to append nextBlock.
Block<T>	nextBlock	The next block to append to blocks.

Returns

Type	Description
InvalidBlockException	The reason why the given blocks are invalid, or null if blocks are valid.

Implements

IBlockPolicy<T>