added transaction sync

blockchain/blockchain.go

@@ -1,11 +1,13 @@
 package blockchain
 
 import (
+ "bytes"
  "crypto/ecdsa"
  "crypto/sha256"
  "encoding/json"
  "fmt"
  "log"
+ "net/http"
  "strings"
  "sync"
  "time"
@@ -80,6 +82,10 @@ func (bc *Blockchain) TransactionPool() []*Transaction {
  return bc.transactionPool
 }
 
+func (bc *Blockchain) ClearTransactionPool() {
+ bc.transactionPool = bc.transactionPool[:0]
+}
+
 func (bc *Blockchain) MarshalJSON() ([]byte, error) {
  return json.Marshal(struct {
  Blocks []*Block `json:"chain"`
@@ -92,13 +98,47 @@ func (bc *Blockchain) CreateBlock(nonce int, previousHash [32]byte) *Block {
  b := NewBlock(nonce, previousHash, bc.transactionPool)
  bc.chain = append(bc.chain, b)
  bc.transactionPool = []*Transaction{}
+
+ for _, n := range bc.neighbors {
+ endpoint := fmt.Sprintf("http://%s/transactions", n)
+ client := &http.Client{}
+ req, _ := http.NewRequest("DELETE", endpoint, nil)
+ resp, err := client.Do(req)
+ if err != nil {
+ log.Printf("%v", resp)
+ }
+ }
+
  return b
 }
 
 func (bc *Blockchain) CreateTransaction(sender string, recipient string, value float32, senderPublicKey *ecdsa.PublicKey, s *utils.Signature) bool {
  isTransacted := bc.AddTransaction(sender, recipient, value, senderPublicKey, s)
- // TODO
- // sync
+
+ if isTransacted {
+ for _, n := range bc.neighbors {
+ publicKeyStr := fmt.Sprintf("%064x%064x", senderPublicKey.X.Bytes(), senderPublicKey.Y.Bytes())
+ signatureStr := s.String()
+ bt := &TransactionRequest{
+ &sender,
+ &recipient,
+ &publicKeyStr,
+ &value,
+ &signatureStr}
+
+ m, _ := json.Marshal(bt)
+ buf := bytes.NewBuffer(m)
+ endpoint := fmt.Sprintf("http://%s/transactions", n)
+
+ client := &http.Client{}
+ req, _ := http.NewRequest("PUT", endpoint, buf)
+ resp, err := client.Do(req)
+ if err != nil {
+ log.Printf("%v", resp)
+ }
+ }
+ }
+
  return isTransacted
 }
 

blockchain_node/blockchain_node.go

@@ -99,6 +99,40 @@ func (bcn *BlockchainNode) Transactions(w http.ResponseWriter, r *http.Request)
  }
  io.WriteString(w, string(m))
 
+ case http.MethodPut:
+ decoder := json.NewDecoder((r.Body))
+ var t blockchain.TransactionRequest
+ err := decoder.Decode(&t)
+ if err != nil {
+ log.Printf("ERROR: %v", err)
+ io.WriteString(w, string(utils.JsonStatus("fail")))
+ return
+ }
+ if !t.Validate() {
+ log.Println("ERROR: missing field(S)")
+ io.WriteString(w, string(utils.JsonStatus("fail")))
+ return
+ }
+ publicKey := utils.String2PublicKey(*t.SenderPublicKey)
+ signature := utils.String2Signature(*t.Signature)
+ bc := bcn.GetBlockchain()
+ isUpdated := bc.AddTransaction(*t.SenderBlockchainAddress, *t.RecipientBlockchainAddress, *t.Value, publicKey, signature)
+
+ w.Header().Add("Content-Type", "application/json")
+ var m []byte
+ if !isUpdated {
+ w.WriteHeader(http.StatusBadRequest)
+ m = utils.JsonStatus("fail")
+ } else {
+ m = utils.JsonStatus("success")
+ }
+ io.WriteString(w, string(m))
+
+ case http.MethodDelete:
+ bc := bcn.GetBlockchain()
+ bc.ClearTransactionPool()
+ io.WriteString(w, string(utils.JsonStatus("success")))
+
  default:
  log.Println("ERROR: Invalid HTTP method")
  w.WriteHeader(http.StatusBadRequest)