Add Pending Transactions

core/Block.go

@@ -12,9 +12,3 @@ type Block struct {
 	Data         []Transaction
 	Nonce        int
 }
-
-// AddTransaction takes in a transaction and adds it to the block
-func (block *Block) AddTransaction(transaction Transaction) error {
-	block.Data = append(block.Data, transaction)
-	return nil
-}

core/Blockchain.go

@@ -10,24 +10,28 @@ import (
 
 // Blockchain struct
 type Blockchain struct {
-	Blocks []Block
+	Blocks              []Block
+	PendingTransactions []Transaction
 }
 
-// AddBlock adds a block to the chain
-func (bc *Blockchain) AddBlock(block Block) {
-
-	log.Print("Mining Block...")
-
+// MineBlock adds a block to the chain
+func (bc *Blockchain) MineBlock() Block {
+	block := Block{}
+	block.Data = bc.PendingTransactions
+	block.Timestamp = time.Now()
+	block.PreviousHash = bc.GetLastHash()
 	// Mine Block
+	log.Print("Mining Block...")
 	for {
 		hash := crypto.CalculateHash(block)
-		if strings.HasPrefix(hash, "0000") {
+		if strings.HasPrefix(hash, "00000") {
 			block.Hash = hash
-			block.Timestamp = time.Now()
-			block.PreviousHash = bc.GetLastHash()
+
 			bc.Blocks = append(bc.Blocks, block)
+			bc.PendingTransactions = []Transaction{}
+
 			log.Print("Block Added: ", block.Hash)
-			break
+			return block
 		}
 		block.Nonce++
 	}
@@ -38,20 +42,17 @@ func (bc *Blockchain) AddBlock(block Block) {
 func NewBlockchain() Blockchain {
 	log.Print("Creating Blockchain...")
 
-	blockchain := Blockchain{Blocks: make([]Block, 0)}
+	blockchain := Blockchain{Blocks: make([]Block, 0), PendingTransactions: make([]Transaction, 0)}
 
-	genesisBlock := generateGenesisBlock()
-	blockchain.AddBlock(genesisBlock)
+	// Mine Genesis Block
+	blockchain.MineBlock()
 	return blockchain
 }
 
-func generateGenesisBlock() Block {
-
-	block := Block{PreviousHash: "0", Timestamp: time.Now()}
-	transaction := Transaction{Amount: 0, Sender: "0", Receiver: "0", Message: "Genesis"}
-	block.AddTransaction(transaction)
-	log.Print("Genesis Block created")
-	return block
+// AddTransaction takes in a transaction and adds it to the block
+func (bc *Blockchain) AddTransaction(transaction Transaction) error {
+	bc.PendingTransactions = append(bc.PendingTransactions, transaction)
+	return nil
 }
 
 // GetLastHash returns the hash of the latest block on the chain

core/blockchain_test.go

@@ -23,7 +23,7 @@ func TestNewBlockchain(t *testing.T) {
 func TestBlockchain_GetLastHash(t *testing.T) {
 	blockchain := NewBlockchain()
 
-	blockchain.AddBlock(Block{})
+	blockchain.MineBlock(Block{})
 	want := blockchain.Blocks[1].Hash
 	got := blockchain.GetLastHash()
 	if got != want {

server/webserver.go

@@ -20,6 +20,8 @@ func ServeHTTP(port string) {
 	blockchain = core.NewBlockchain()
 
 	http.HandleFunc("/", handleMain)
+	http.HandleFunc("/mine_block", handleMineBlock)
+	http.HandleFunc("/pending_transactions", handleListPendingTransactions)
 
 	log.Print("Listening on port ", port)
 	if err := http.ListenAndServe(port, nil); err != nil {
@@ -32,7 +34,7 @@ func handleMain(w http.ResponseWriter, r *http.Request) {
 	case "GET":
 		handleListBlocks(w, r)
 	case "POST":
-		handleAddBlock(w, r)
+		handleAddTransaction(w, r)
 	}
 }
 
@@ -45,14 +47,24 @@ func handleListBlocks(w http.ResponseWriter, r *http.Request) {
 	json.NewEncoder(w).Encode(blockchain.Blocks)
 }
 
-func handleAddBlock(w http.ResponseWriter, r *http.Request) {
+func handleAddTransaction(w http.ResponseWriter, r *http.Request) {
 	decoder := json.NewDecoder(r.Body)
-	var receivedBlock core.Block
-	err := decoder.Decode(&receivedBlock)
+	var receivedTransaction core.Transaction
+	err := decoder.Decode(&receivedTransaction)
 	if err == nil {
-		log.Println(receivedBlock.Data, " received")
-		go blockchain.AddBlock(receivedBlock)
+		log.Println("Transaction from", receivedTransaction.Sender, "to", receivedTransaction.Receiver, "received")
+
+		go blockchain.AddTransaction(receivedTransaction)
 	} else {
 		handleError(err, w, r)
 	}
 }
+
+func handleMineBlock(w http.ResponseWriter, r *http.Request) {
+	block := blockchain.MineBlock()
+	json.NewEncoder(w).Encode(block)
+}
+
+func handleListPendingTransactions(w http.ResponseWriter, r *http.Request) {
+	json.NewEncoder(w).Encode(blockchain.PendingTransactions)
+}