Implement block height

block.go

@@ -14,11 +14,12 @@ type Block struct {
 	PrevBlockHash []byte
 	Hash          []byte
 	Nonce         int
+	Height        int
 }
 
 // NewBlock creates and returns Block
-func NewBlock(transactions []*Transaction, prevBlockHash []byte) *Block {
-	block := &Block{time.Now().Unix(), transactions, prevBlockHash, []byte{}, 0}
+func NewBlock(transactions []*Transaction, prevBlockHash []byte, height int) *Block {
+	block := &Block{time.Now().Unix(), transactions, prevBlockHash, []byte{}, 0, height}
 	pow := NewProofOfWork(block)
 	nonce, hash := pow.Run()
 
@@ -30,7 +31,7 @@ func NewBlock(transactions []*Transaction, prevBlockHash []byte) *Block {
 
 // NewGenesisBlock creates and returns genesis Block
 func NewGenesisBlock(coinbase *Transaction) *Block {
-	return NewBlock([]*Transaction{coinbase}, []byte{})
+	return NewBlock([]*Transaction{coinbase}, []byte{}, 0)
 }
 
 // HashTransactions returns a hash of the transactions in the block

blockchain.go

@@ -172,6 +172,7 @@ func (bc *Blockchain) Iterator() *BlockchainIterator {
 // MineBlock mines a new block with the provided transactions
 func (bc *Blockchain) MineBlock(transactions []*Transaction) *Block {
 	var lastHash []byte
+	var lastHeight int
 
 	for _, tx := range transactions {
 		if bc.VerifyTransaction(tx) != true {
@@ -183,13 +184,18 @@ func (bc *Blockchain) MineBlock(transactions []*Transaction) *Block {
 		b := tx.Bucket([]byte(blocksBucket))
 		lastHash = b.Get([]byte("l"))
 
+		blockData := b.Get(lastHash)
+		block := DeserializeBlock(blockData)
+
+		lastHeight = block.Height
+
 		return nil
 	})
 	if err != nil {
 		log.Panic(err)
 	}
 
-	newBlock := NewBlock(transactions, lastHash)
+	newBlock := NewBlock(transactions, lastHash, lastHeight+1)
 
 	err = bc.db.Update(func(tx *bolt.Tx) error {
 		b := tx.Bucket([]byte(blocksBucket))