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2 b1 J% z# r$ t7 l. R' e+ h* Y" r
PrevBlockHash string //上一个区块的hash值$ R) J& |: m4 t5 ?
Hash string //当前区块哈希值3 Y8 d( p3 t) S: C6 [; K! \
Data string //区块数据
; y# y7 [8 J3 f7 `$ E
} A$ b, |$ `6 T# c
//计算Hash( T" x# h+ t& t5 D" m5 o: L
func calculateHash(b *Block) string {/ k' S b1 X% h- L) N
blockData := string(b.Index) + string(b.Timestamp) + b.PrevBlockHash
# Z2 c! q0 |( {$ z* V& ~9 Z
hashInBytes := sha256.Sum256([]byte(blockData)). \8 z, V8 f0 B: [- ~6 w& G0 u3 h U+ G
return hex.EncodeToString(hashInBytes[:])
# f+ }+ |3 v3 \- \. {
}

复制代码

//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
1 ^- h% U4 t8 C6 i
& Y6 p6 W6 f5 M/ J! {& ~6 v# T
import ( j: i: [3 u5 u) ?+ O! d/ F: T
"encoding/json"
1 y6 r1 F! v, Q' ~/ X! S0 T8 A& }8 G8 ~
"BlockChain/core"
- q) c; b9 m2 c2 c0 \& @
"io"
1 [" w: S( Y( k4 t
"net/http"8 @0 ?0 B4 X! ~ n9 d
)! ]! g5 J1 `+ b2 `/ M
6 j1 B, o- ^7 ?) g7 c, g
var blockChain *core.BlockChain3 D2 E/ R) s6 h, P! W
g. z+ }4 p7 D
func run() {/ q! [- r& D9 _5 x
http.HandleFunc("/block_chain/get", blockChainGetHandle)8 o/ a! p, V( v! w) h
http.HandleFunc("/block_chain/write", blockChainWriteHandle)
, u9 u4 a B" m0 r4 A: J) w; d4 w
http.ListenAndServe(":8332", nil)
) d9 h' [4 k) ]8 L8 k* r. t
}
- P7 b" ^" W+ q& m
6 p6 ?4 a2 T4 V+ m) c. E! `9 J
func blockChainGetHandle(w http.ResponseWriter, r *http.Request) {
' ^. x: S# ~; x: O+ K6 M
bytes, err := json.Marshal(blockChain)
- u# [% n9 r9 A* A9 }
if err != nil {/ u4 t F5 h% O. D* C/ M v. p$ m0 r
http.Error(w, err.Error(), http.StatusInternalServerError)8 P! W$ \. z! ^4 r# @$ q" X
return
U; u' F8 D9 @ k- ~" n1 h3 s: x
}
$ P# h4 Y/ e# z
io.WriteString(w, string(bytes))% |% t9 Y f9 {! e5 l7 Z8 }8 O3 @; @
}
& T8 k" S3 j. y/ p
/ u8 e5 i- X7 v9 B" ]: \
func blockChainWriteHandle(w http.ResponseWriter, r *http.Request) {! F8 o# d9 v" W) t' h
blockData := r.URL.Query().Get("data")
blockChain.SendData(blockData). L/ E! e e4 w3 N, `$ J- ~
blockChainGetHandle(w, r)
: t5 z6 w4 j3 i- a4 D) _
}
' i/ O/ A3 ^3 O% \. N6 W6 u6 l7 d2 s: K
2 ]9 l4 b2 J; p/ d6 @4 o% o, A
func main() {
2 [! y5 E3 j# w
blockChain = core.NewBlockChain()
" L, s+ i4 Q6 e1 ?( V
run()
; y+ o4 L6 z# y4 m! M6 a
}

复制代码

通过两部分代码实现简易区块链的RPC调用

浏览过的版块