blockchain

Documentation

Index

• Constants
• func DBexists() bool
• func Handle(err error)
• type Block
  • func CreateBlock(txs []*Transaction, prevHash []byte) *Block
  • func Deserialize(data []byte) *Block
  • func Genesis(coinbase *Transaction) *Block
  • func (bloc *Block) HashTransactions() []byte
  • func (b *Block) Serialize() []byte
• type BlockChain
  • func ContinueBlockChain(address string) *BlockChain
  • func InitBlockChain(address string) *BlockChain
  • func (chain *BlockChain) AddBlock(transactions []*Transaction)
  • func (chain *BlockChain) FindSpendableOutputs(address string, amount int) (int, map[string][]int)
  • func (chain *BlockChain) FindTransactions(address string) []Transaction
  • func (chain *BlockChain) FindUTXO(address string) []TxOutput
  • func (chain *BlockChain) FindUnspentTransactions(address string) []Transaction
  • func (chain *BlockChain) Iterator() *BlockChainIterator
• type BlockChainIterator
  • func (iterator *BlockChainIterator) Next() *Block
• type ProofOfWork
  • func NewProofOfWork(b *Block) *ProofOfWork
  • func (pow *ProofOfWork) InitData(nonce int) []byte
  • func (pow *ProofOfWork) Run() (int, []byte)
  • func (pow *ProofOfWork) Validate() bool
• type Transaction
  • func CoinbaseTx(toAddress, data string) *Transaction
  • func NewTransaction(from, to string, amount int, chain *BlockChain) *Transaction
  • func (tx *Transaction) IsCoinbase() bool
  • func (tx *Transaction) SetID()
• type TxInput
  • func (in *TxInput) CanUnlock(data string) bool
• type TxOutput
  • func (out *TxOutput) CanBeUnlocked(data string) bool

Constants

const Difference = 12 // Possbile TODO: Change this constant to a dynamic algorithim

The Greater the Difference in the algorithm, the harder the work will be to compute

Functions

func DBexists

func DBexists() bool

func Handle

func Handle(err error)

Types

type Block

type Block struct {
	Hash         []byte
	Transactions []*Transaction
	PrevHash     []byte
	Nonce        int
}

Block is a single unit in the blockchain

func CreateBlock

func CreateBlock(txs []*Transaction, prevHash []byte) *Block

CreateBlock will create a new block, but not add it to the chain

func Deserialize

func Deserialize(data []byte) *Block

func Genesis

func Genesis(coinbase *Transaction) *Block

Genesis needs to be the first block in a chain, as the first block doesn't have an address to point back to

func (*Block) HashTransactions

func (bloc *Block) HashTransactions() []byte

func (*Block) Serialize

func (b *Block) Serialize() []byte

type BlockChain

type BlockChain struct {
	LastHash []byte
	Database *badger.DB
}

BlockChain is an array of block pointers

func ContinueBlockChain

func ContinueBlockChain(address string) *BlockChain

ContinueBlockChain will be called to append to an existing blockchain

func InitBlockChain

func InitBlockChain(address string) *BlockChain

InitBlockChain will be what starts a new blockChain

func (*BlockChain) AddBlock

func (chain *BlockChain) AddBlock(transactions []*Transaction)

AddBlock Will add a Block type unit to a blockchain

func (*BlockChain) FindSpendableOutputs

func (chain *BlockChain) FindSpendableOutputs(address string, amount int) (int, map[string][]int)

func (*BlockChain) FindTransactions

func (chain *BlockChain) FindTransactions(address string) []Transaction

func (*BlockChain) FindUTXO

func (chain *BlockChain) FindUTXO(address string) []TxOutput

func (*BlockChain) FindUnspentTransactions

func (chain *BlockChain) FindUnspentTransactions(address string) []Transaction

func (*BlockChain) Iterator

func (chain *BlockChain) Iterator() *BlockChainIterator

Iterator takes our BlockChain struct and returns it as a BlockCHainIterator struct

type BlockChainIterator

type BlockChainIterator struct {
	CurrentHash []byte
	Database    *badger.DB
}

func (*BlockChainIterator) Next

func (iterator *BlockChainIterator) Next() *Block

Next will iterate through the BlockChainIterator

type ProofOfWork

type ProofOfWork struct {
	Block  *Block
	Target *big.Int
}

func NewProofOfWork

func NewProofOfWork(b *Block) *ProofOfWork

func (*ProofOfWork) InitData

func (pow *ProofOfWork) InitData(nonce int) []byte

InitData takes your block and adds a nonce (counter/incrementer) to it.

func (*ProofOfWork) Run

func (pow *ProofOfWork) Run() (int, []byte)

Run will hash our data, turn that hash into a big int, and then compare that big int to our Target which is inside the Proof Of Work Struct

func (*ProofOfWork) Validate

func (pow *ProofOfWork) Validate() bool

Validate will check our Run() function performed as expected

type Transaction

type Transaction struct {
	ID      []byte
	Inputs  []TxInput
	Outputs []TxOutput
}

func CoinbaseTx

func CoinbaseTx(toAddress, data string) *Transaction

CoinbaseTx is the function that will run when someone on a node succesfully "mines" a block. The reward inside as it were.

func NewTransaction

func NewTransaction(from, to string, amount int, chain *BlockChain) *Transaction

func (*Transaction) IsCoinbase

func (tx *Transaction) IsCoinbase() bool

func (*Transaction) SetID

func (tx *Transaction) SetID()

TxOutput represents a transaction in the blockchain For Example, I sent you 5 coins. Value would == 5, and it would have my unique PubKey

type TxInput

type TxInput struct {
	ID []byte
	//ID will find the Transaction that a specific output is inside of
	Out int
	//Out will be the index of the specific output we found within a transaction.
	//For example if a transaction has 4 outputs, we can use this "out" field to specify which output we are looking for
	Sig string
}

TxInput is represntative of a reference to a previous TxOutput

func (*TxInput) CanUnlock

func (in *TxInput) CanUnlock(data string) bool

type TxOutput

type TxOutput struct {
	Value int
	//Value would be representative of the amount of coins in a transaction
	PubKey string
}

func (*TxOutput) CanBeUnlocked

func (out *TxOutput) CanBeUnlocked(data string) bool