@ethereumjs/block
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Implements schema and functions related to Ethereum's block. |
---|
Note: this README
reflects the state of the library from v3.0.0
onwards. See README
from the standalone repository for an introduction on the last preceding release.
INSTALL
npm install @ethereumjs/block
USAGE
Introduction
There are three static factories to instantiate a Block
:
Block.fromBlockData(blockData: BlockData = {}, opts?: BlockOptions)
Block.fromRLPSerializedBlock(serialized: Buffer, opts?: BlockOptions)
Block.fromValuesArray(values: BlockBuffer, opts?: BlockOptions)
For BlockHeader
instantiation analog factory methods exists, see API docs linked below.
Instantiation Example:
import { BlockHeader } from '@ethereumjs/block'
const headerData = {
number: 15,
parentHash: '0x6bfee7294bf44572b7266358e627f3c35105e1c3851f3de09e6d646f955725a7',
difficulty: 131072,
gasLimit: 8000000,
timestamp: 1562422144,
}
const header = BlockHeader.fromHeaderData(headerData)
Properties of a Block
or BlockHeader
object are frozen with Object.freeze()
which gives you enhanced security and consistency properties when working with the instantiated object. This behavior can be modified using the freeze
option in the constructor if needed.
API Usage Example:
try {
await block.validate(blockchain)
} catch (err) {
}
EIP-1559 Blocks
This library supports the creation of EIP-1559 compatible blocks starting with v3.3.0
.
To instantiate an EIP-1559 block the hardfork parameter on the Common
instance needs to be explicitly set to london
(default is still istanbul
):
import { BN } from 'ethereumjs-util'
import { Block } from '@ethereumjs/block'
import Common, { Chain, Hardfork } from '@ethereumjs/common'
const common = new Common({ chain: Chain.Mainnet, hardfork: Hardfork.London })
const block = Block.fromBlockData({
header: {
baseFeePerGas: new BN(10),
gasLimit: new BN(100),
gasUsed: new BN(60)
}
}, { common })
block.header.calcNextBaseFee().toNumber()
const blockWithMatchingBaseFee = Block.fromBlockData({
header: {
baseFeePerGas: parentHeader.calcNextBaseFee(),
gasLimit: new BN(100),
gasUsed: new BN(60)
}
}, { common })
EIP-1559 blocks have an extra baseFeePerGas
field (default: new BN(7)
) and can encompass FeeMarketEIP1559Transaction
txs (type 2
) (supported by @ethereumjs/tx
v3.2.0
or higher) as well as Transaction
legacy txs (internal type 0
) and AccessListEIP2930Transaction
txs (type 1
).
Consensus Types
The block library supports the creation as well as format and consensus validation of PoW ethash
and PoA clique
blocks.
Ethash/PoW
An Ethash/PoW block can be instantiated as follows:
import { Block } from '@ethereumjs/block'
import Common, { Chain } from '@ethereumjs/common'
const common = new Common({ chain: Chain.Mainnet })
console.log(common.consensusType())
console.log(common.consensusAlgorithm())
const block = Block.fromBlockData({}, { common })
To validate that the difficulty of the block matches the canonical difficulty use block.validate(blockchain)
.
To calculate the difficulty when creating the block pass in the block option calcDifficultyFromHeader
with the preceding (parent) BlockHeader
.
Clique/PoA (since v3.1.0)
A clique block can be instantiated as follows:
import { Block } from '@ethereumjs/block'
import Common, { Chain } from '@ethereumjs/common'
const common = new Common({ chain: Chain.Goerli })
console.log(common.consensusType())
console.log(common.consensusAlgorithm())
const block = Block.fromBlockData({}, { common })
For clique PoA BlockHeader.validate()
function validates the various Clique/PoA-specific properties (extraData
checks and others, see API documentation) and BlockHeader.validateConsensus()
can be used to properly validate that a Clique/PoA block has the correct signature.
For sealing a block on instantiation you can use the cliqueSigner
constructor option:
const cliqueSigner = Buffer.from('PRIVATE_KEY_HEX_STRING', 'hex')
const block = Block.fromHeaderData(headerData, { cliqueSigner })
Additionally there are the following utility methods for Clique/PoA related functionality in the BlockHeader
class:
BlockHeader.validateCliqueDifficulty(blockchain: Blockchain): boolean
BlockHeader.cliqueSigHash()
BlockHeader.cliqueIsEpochTransition(): boolean
BlockHeader.cliqueExtraVanity(): Buffer
BlockHeader.cliqueExtraSeal(): Buffer
BlockHeader.cliqueEpochTransitionSigners(): Address[]
BlockHeader.cliqueVerifySignature(signerList: Address[]): boolean
BlockHeader.cliqueSigner(): Address
See the API docs for detailed documentation. Note that these methods will throw if called in a non-Clique/PoA context.
Casper/PoS (since v3.5.0) (experimental)
Merge-friendly Casper/PoS blocks have been introduced along with the v3.5.0
release. Proof-of-Stake compatible execution blocks come with their own set of header field simplifications and associated validation rules. The difficulty is set to 0
since not relevant anymore, just to name an example. For a full list of changes see EIP-3675.
You can instantiate a Merge/PoS block like this:
import { Block } from '@ethereumjs/block'
import Common, { Chain, Hardfork } from '@ethereumjs/common'
const common = new Common({ chain: Chain.Mainnet, hardfork: Hardfork.Merge, })
const block = Block.fromBlockData({
}, { common })
Note that all Merge
respectively Casper/PoS
related functionality is still considered experimental
.
API
Documentation
TESTING
Tests in the tests
directory are partly outdated and testing is primarily done by running the BlockchainTests
from within the @ethereumjs/vm package.
To avoid bloating this repository with ethereum/tests JSON files, we usually copy specific JSON files and wrap them with some metadata (source, date, commit hash). There's a helper to aid in that process and can be found at wrap-ethereum-test.sh.
EthereumJS
See our organizational documentation for an introduction to EthereumJS
as well as information on current standards and best practices.
If you want to join for work or do improvements on the libraries have a look at our contribution guidelines.
LICENSE
MPL-2.0