Add basic structure

core/block.go

@@ -0,0 +1,33 @@
+package core
+
+// Block represents a block in the blockchain
+type Block struct {
+	BlockNumber		uint64
+	Hash			[]byte
+	PreviousHash	[]byte
+	TimeStamp		uint64	// Unix timestamp (https://www.unixtimestamp.com/)
+	Data			string	// FIXME It will be changed to some struct contains txs.
+}
+
+// NewBlock creates and returns new block
+func NewBlock(blockNumber uint64, previousHash []byte, data string) *Block {
+	// TODO
+	return &Block{blockNumber, []byte{}, previousHash, 1234567890, data}
+}
+
+// NewGenesisBlock creates and returns genesis block
+func NewGenesisBlock() *Block {
+	return NewBlock(0, []byte{}, "Planus Genesis Block")
+}
+
+// Serialize serializes block to byte array
+func (block *Block) Serialize() []byte {
+	// TODO
+	return []byte{}
+}
+
+// Deserialize deserializes byte array to block
+func Deserialize(bytes []byte) *Block {
+	// TODO
+	return &Block{}
+}

core/blockchain.go

@@ -0,0 +1,55 @@
+package core
+
+import (
+	"log"
+)
+
+// Blockchain represents a list of connected blocks
+type Blockchain struct {
+	 blocks []*Block
+}
+
+// NewBlockchain creates a blockchain with genesis block
+func NewBlockchain() *Blockchain {
+	return &Blockchain{[]*Block{NewGenesisBlock()}}
+}
+
+// AddBlock adds the block into blockchain
+func (blockchain *Blockchain) AddBlock(block *Block) {
+	if (blockchain.isValidBlock(block)) {
+		blockchain.blocks = append(blockchain.blocks, block)
+	}
+}
+
+// CreateBlock creates a new block and returns it
+func (blockchain *Blockchain) CreateBlock(data string) *Block {
+	return NewBlock(
+		blockchain.GetLatestBlockNumber() + 1,
+		blockchain.GetLatestBlock().PreviousHash, data)
+}
+
+// GetLatestBlock returns latest block in the blockchain
+func (blockchain *Blockchain) GetLatestBlock() *Block {
+	return blockchain.blocks[blockchain.GetLatestBlockNumber()]
+}
+
+// GetLatestBlockNumber returns latest block number in the blockchain
+func (blockchain *Blockchain) GetLatestBlockNumber() uint64 {
+	// FIXME Use other methods instead of len() that supports unit64
+	return (uint64)(len(blockchain.blocks) - 1)
+}
+
+// isValidBlock validates block and returns valid or not
+func (blockchain *Blockchain) isValidBlock(block *Block) bool {
+	// TODO Validate block number with GetLatestBlockNumber()
+	// TODO Validate previous block hash with GetLatestBlock()
+	// TODO Validate new block hash
+	return true
+}
+
+// FOR TEST
+func (blockchain *Blockchain) ShowBlockchainForDebug() {
+	for idx, block := range blockchain.blocks {
+		log.Println(idx, block.Data)
+	}
+}

main.go

@@ -0,0 +1,14 @@
+package main
+
+import (
+	"./core"
+)
+
+func main() {
+	blockchain := core.NewBlockchain()
+	blockchain.AddBlock(blockchain.CreateBlock("New Block 1"))
+	blockchain.AddBlock(blockchain.CreateBlock("New Block 2"))
+
+	// Test
+	blockchain.ShowBlockchainForDebug()
+}