SYNOPSIS

or #vaporyjs on freenode

A module to store and interact with blocks.

INSTALL

npm install vaporyjs-blockchain

API

vaporyjs-blockchain

A module to store and interact with blocks

• Blockchain
  • new Blockchain(blockDB, detailsDB)
  • BlockChain Properties
  • BlockChain methods
    • blockchain.init(cb)
    • blockchain.addBlock(block, [callback])
    • blockchain.getBlock(hash, [callback])
    • blockchain.getBlockInfo(hash, cb)
    • blockchain.getBlockHashes(parentHash, count, cb)
    • blockchain.getBlockChain(startingHashes, count, cb)
    • blockchain.selectNeededHashes(hashes, cb)

Blockchain

Implements functions for retrieving, manipulating and storing Vapory's blockchain

new Blockchain(blockDB, detailsDB)

Creates new Blockchain object

• blockDB - the database that backs the Blockchain. the db object is tested with levelup but should with any store that implements put, get and del.
• detailsDB - this is the same as blockDB except this db houses the meta infomation about the blockchain.

BlockChain Properties

• head - The Head, the block that has the most weight
• parentHead- The parent of the head block
• genesisHash - The hash of the genesis block
• height - The height of the blockchain
• totallDifficulty - The totall difficulty which is the some of a the difficulty of all the prevous blocks

BlockChain methods

blockchain.init(cb)

Initializes the blockchain. This must be done before you can use the blockchain

• cb - the callback

blockchain.addBlock(block, [callback])

Adds a block to the blockchain.

• block - the block to be added to the blockchain
• callback - the callback. It is given two parameters err and the saved block

blockchain.getBlock(hash, [callback])

Gets a block by it hash.

• hash - the block's hash
• callback - the callback. It is given two parameters err and the found block if any.

blockchain.getBlockInfo(hash, cb)

Retrieves meta infromation about the block and passed it to the callback

• hash - the hash of the block as a Buffer or a hex String
• cb - the callback which is passed an Object containing two propties parent, the hash of the this block's parents and children an Array of hashes of children blocks.

blockchain.getBlockHashes(parentHash, count, cb)

Gets a segment of the blockchain starting at the parent hash and contuning for count blocks returning an array of block hashes orders from oldest to youngest.

• parentHash - the block to start from. Given as a Buffer or a hex String
• count - a Number specifing how many block hashes to return
• cb - the callback which is give an array of block hashes

blockchain.getBlockChain(startingHashes, count, cb)

gets a section of the blockchain in a form of an array starting at the parent hash, up count blocks

• startingHashes - an array of hashes or a single hash to start returning the chain from. The first hash in the array that is found in the blockchain will be used.
• count - the max number of blocks to return
• callback - the callback. It is given two parameters err and blockchain. err is any errors. If none of the starting hashes were found err will be notFound. blockchain is an array of blocks.

blockchain.selectNeededHashes(hashes, cb)

Given an ordered array, returns to the callback an array of hashes that are not in the blockchain yet.

• hashes - an Array hashes
• cb - the callback