使用go语言编写简易Blockchain实现web调用RPC过程

在本机端口进行查询由于是第一次运行该链生成创世区块

通过http实现RPC命令的调用  实现添加块

查询当前所有块的信息

这里只做了两个命令分别是get和write
源代码如下
基础功能的实现

package core
import (
      "crypto/sha256"
      "encoding/hex"
      "time"
)
//定义区块
type Block struct {
      Index       int64  //区块编号

Timestamp int64 //区块时间戳
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PrevBlockHash string //上一个区块的hash值
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Hash string //当前区块哈希值. g1 V8 o: ^$ H+ \
Data string //区块数据
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//计算Hash: |) q* d" h$ |$ `+ A$ L0 _ h `
func calculateHash(b *Block) string {
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blockData := string(b.Index) + string(b.Timestamp) + b.PrevBlockHash& j. d" b' \4 F( c5 L5 M% N
hashInBytes := sha256.Sum256([]byte(blockData))
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return hex.EncodeToString(hashInBytes[:])
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}

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//生成新的区块
func GenerateNewBlock(preBlock *Block, data string) *Block {
      newBlock := &Block{}
      newBlock.Index = preBlock.Index + 1
      newBlock.PrevBlockHash = preBlock.Hash
      newBlock.Timestamp = time.Now().Unix()
      newBlock.Hash = calculateHash(newBlock)
      newBlock.Data = data
      return newBlock
}

//生成创始区块
func GenerateGenesisBlock() *Block {
      preBlock := &Block{}
      preBlock.Index = -1
      preBlock.Hash = ""
      return GenerateNewBlock(preBlock, "Genesis Block")
}
将基础功能实现的块进行链接实现blockchain
package core

import (
      "fmt"
      "log"
)

//定义区块链
type BlockChain struct {
      Blocks []*Block
}

//创建一个区块链
func NewBlockChain() *BlockChain {
      genesisBlock := GenerateGenesisBlock()
      blockChain := &BlockChain{}
      blockChain.AppendBlock(genesisBlock)
      return blockChain
}

//记录区块数据
func (bc *BlockChain) SendData(data string) {
      preBlock := bc.Blocks[len(bc.Blocks)-1]
      newBlock := GenerateNewBlock(preBlock, data)
      bc.AppendBlock(newBlock)
}

//往区块链添加区块
func (bc *BlockChain) AppendBlock(newBlock *Block) {
      if len(bc.Blocks) == 0 {
            bc.Blocks = append(bc.Blocks, newBlock)
            return
      }
      if isValid(newBlock, bc.Blocks[len(bc.Blocks)-1]) {
            bc.Blocks = append(bc.Blocks, newBlock)
      } else {
            log.Fatal("invalid block")
      }
      return
}

//输出区块链信息
func (bc *BlockChain) Print() {
      for _, block := range bc.Blocks {
            fmt.Printf("Index : %d\n", block.Index)
            fmt.Printf("Prev.Hash : %s\n", block.PrevBlockHash)
            fmt.Printf("Curr.Hash : %s\n", block.Hash)
            fmt.Printf("Curr.Data : %s\n", block.Data)
            fmt.Printf("Curr.Timestamp : %d\n", block.Timestamp)
            fmt.Println("==========================================")
      }
}

//验证区块
func isValid(newBlock *Block, oldBlock *Block) bool {
      if newBlock.Index-1 != oldBlock.Index {
            return false
      }
      if newBlock.PrevBlockHash != oldBlock.Hash {
            return false
      }
      if calculateHash(newBlock) != newBlock.Hash {
            return false
      }
      return true
}
实现RPC接口的交互

package main$ C1 m# n! E8 j+ c3 W
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import (
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"encoding/json"
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"BlockChain/core"
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"io"9 I, c2 z' P9 t
"net/http"
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)
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var blockChain *core.BlockChain
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func run() {) {9 }) T5 \9 E, R( x6 ~2 c8 W
http.HandleFunc("/block_chain/get", blockChainGetHandle)
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http.HandleFunc("/block_chain/write", blockChainWriteHandle)
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http.ListenAndServe(":8332", nil)
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}
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func blockChainGetHandle(w http.ResponseWriter, r *http.Request) {
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bytes, err := json.Marshal(blockChain)
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if err != nil {, B! \5 Y- c; |
http.Error(w, err.Error(), http.StatusInternalServerError)0 `# q" |" Q! P! \) z/ t& y& C f) t
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io.WriteString(w, string(bytes))
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func blockChainWriteHandle(w http.ResponseWriter, r *http.Request) {+ Z h4 H8 }9 O2 P l
blockData := r.URL.Query().Get("data")6 t: ?5 P0 B, I2 r! H+ q
blockChain.SendData(blockData)8 k( [5 }0 r% |' O4 h5 K7 `+ x4 t4 q
blockChainGetHandle(w, r)
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}
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func main() {4 k2 d0 y5 L2 N1 ^
blockChain = core.NewBlockChain()
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run() @( G2 c$ K2 G4 j' N9 W- n6 [6 \+ b
}

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通过两部分代码实现简易区块链的RPC调用

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