added consensus algorism

blockchain/block.go

@@ -67,10 +67,10 @@ func (b *Block) MarshalJSON() ([]byte, error) {
 func (b *Block) UnmarshalJSON(data []byte) error {
  var previousHash string
  v := &struct {
- Timestamp *int64 `json: "timestamp"`
- Nonce *int `json: "nonce"`
- PreviousHash *string `json: "previous_hash"`
- Transactions *[]*Transaction `json: "transactions"`
+ Timestamp *int64 `json:"timestamp"`
+ Nonce *int `json:"nonce"`
+ PreviousHash *string `json:"previous_hash"`
+ Transactions *[]*Transaction `json:"transactions"`
  }{
  Timestamp: &b.timestamp,
  Nonce: &b.nonce,

blockchain/blockchain.go

@@ -54,6 +54,8 @@ func (bc *Blockchain) Chain() []*Block {
 
 func (bc *Blockchain) Run() {
  bc.StartSyncNeighbors()
+ bc.ResolveConflicts()
+ // bc.StartMining()
 }
 
 func (bc *Blockchain) SetNeightbors() {
@@ -98,6 +100,18 @@ func (bc *Blockchain) MarshalJSON() ([]byte, error) {
  })
 }
 
+func (bc *Blockchain) UnmarshalJSON(data []byte) error {
+ v := &struct {
+ Blocks *[]*Block `json:"chain"`
+ }{
+ Blocks: &bc.chain,
+ }
+ if err := json.Unmarshal(data, &v); err != nil {
+ return err
+ }
+ return nil
+}
+
 func (bc *Blockchain) CreateBlock(nonce int, previousHash [32]byte) *Block {
  b := NewBlock(nonce, previousHash, bc.transactionPool)
  bc.chain = append(bc.chain, b)
@@ -228,6 +242,17 @@ func (bc *Blockchain) Mining() bool {
  previousHash := bc.LastBlock().Hash()
  bc.CreateBlock(nonce, previousHash)
  log.Println("action=mining, status=success")
+
+ for _, n := range bc.neighbors {
+ endpoint := fmt.Sprintf("http://%s/consensus", n)
+ client := &http.Client{}
+ req, _ := http.NewRequest("PUT", endpoint, nil)
+ resp, err := client.Do(req)
+ if err != nil {
+ log.Printf("%v", resp)
+ }
+ }
+
  return true
 }
 
@@ -298,7 +323,7 @@ func (bc *Blockchain) ResolveConflicts() bool {
  log.Printf("Resolved conflicts: blockchain was replaced")
  return true
  }
- log.Printf("Resolved conflicts: blockchain was nor replaced")
+ log.Printf("Resolved conflicts: blockchain was not replaced")
  return false
 }
 
@@ -313,15 +338,3 @@ func (ar *AmountResponse) MarshalJSON() ([]byte, error) {
  Amount: ar.Amount,
  })
 }
-
-func (bc *Blockchain) UnmarshalJSON(data []byte) error {
- v := &struct {
- Blocks *[]*Block `json: "chain"`
- }{
- Blocks: &bc.chain,
- }
- if err := json.Unmarshal(data, &v); err != nil {
- return err
- }
- return nil
-}

blockchain_node/blockchain_node.go

@@ -192,6 +192,24 @@ func (bcn *BlockchainNode) Amount(w http.ResponseWriter, r *http.Request) {
  }
 }
 
+func (bcn *BlockchainNode) Consensus(w http.ResponseWriter, r *http.Request) {
+ switch r.Method {
+ case http.MethodPut:
+ bc := bcn.GetBlockchain()
+ replaced := bc.ResolveConflicts()
+
+ w.Header().Add("Content-Type", "application/json")
+ if replaced {
+ io.WriteString(w, string(utils.JsonStatus("success")))
+ } else {
+ io.WriteString(w, string(utils.JsonStatus("fail")))
+ }
+ default:
+ log.Printf("ERROR: Invalid HTTP method")
+ w.WriteHeader(http.StatusBadRequest)
+ }
+}
+
 func (bcn *BlockchainNode) Run() {
  bcn.GetBlockchain().Run()
 
@@ -200,6 +218,7 @@ func (bcn *BlockchainNode) Run() {
  http.HandleFunc("/mine", bcn.Mine)
  http.HandleFunc("/mine/start", bcn.StartMine)
  http.HandleFunc("/amount", bcn.Amount)
+ http.HandleFunc("/consensus", bcn.Consensus)
 
  log.Fatal(http.ListenAndServe("0.0.0.0:"+strconv.Itoa(int(bcn.Port())), nil))
 }

utils/neighbors.go

@@ -15,7 +15,7 @@ func IsFoundNode(host string, port uint16) bool {
 
  _, err := net.DialTimeout("tcp", target, 1*time.Second)
  if err != nil {
- fmt.Printf("%s %v\n", target, err)
+ // fmt.Printf("%s %v\n", target, err)
  return false
  }
  return true