# token_nft_admin

**Repository Path**: blackcoder/token_nft_admin

## Basic Information

- **Project Name**: token_nft_admin
- **Description**: nft合约对应的后台
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2024-07-02
- **Last Updated**: 2024-07-09

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# token_nft_admin
### 合约项目:https://gitee.com/blackcoder/token_nft.git

#### 介绍

- 监听合约事件
- web3j处理REC721和REC720的代币转移
- 钱包登录

#### 软件架构

- springboot2.x
- mybatis-plus
- Mysql5.7
- redis5.x
- swagger3 



#### 安装教程

1.  jdk8+
2.  Mysql5.7
3.  redis5.x
4.  maven


#### web3j核心功能-链上做交互

###### 监听(获取)链上信息：1.监听区块高度范围 2.监听的合约地址
`EthLog ethLog = web3j.ethGetLogs(new EthFilter(DefaultBlockParameter.valueOf(startScanBlock), DefaultBlockParameter.valueOf(lastScanBlock), pledgeAddress)).send(); `

###### 执行链上方法（代币转移，更新链上数据状态......）
1.创建合约对象-获取合约的abi和bin文件。使用第三方工具（web3j）执行命令，最终会得到对应的Class文件.

```
//关于truffle项目中：build/contarcts下有N多个json文件。找对合约名字对应文件。找到abi和bytecode(bin)字段的内容。
格式：web3j generate solidity -b <文件名>.bin -a <文件名>.abi -o <输出目录> -p <包路径>
web3j generate solidity -b NftAuction.bin -a NftAuction.abi -o java/ -p com.baiye
```
2.创建的合约对象，一般实际开发中都是以Bean的形式被初始化

```
@Bean("mwToken")
    @SneakyThrows
    public MwToken mwToken(Web3j web3j) {
        TransactionManager transactionManager = new RawTransactionManager(web3j, Credentials.create(walletNftRefundPriKey), 1337);
        MwToken mwToken = MwToken.load(mwTokenContractAddress, web3j, transactionManager, new StaticGasProvider(new BigInteger(gasPriceValue), new BigInteger(gasLimitValue)));
        return mwToken;
    }

    @Bean("mwNftToken")
    @SneakyThrows
    public MwNft mwNftToken(Web3j web3j) {
        TransactionManager transactionManager = new RawTransactionManager(web3j, Credentials.create(walletNftRefundPriKey), 1337);
        MwNft mwNftToken = MwNft.load(mwNftContractAddress, web3j, transactionManager, new StaticGasProvider(new BigInteger(gasPriceValue), new BigInteger(gasLimitValue)));
        return mwNftToken;
    }
```
3. 调用链上方法：


```
   @Autowired
    private NftAuction nftAuction;

    @Autowired
    private MwToken mwToken;

   @Async
    public void endAuction() {
        // 实际：从数据库中加载拍卖的所有过期nft
        for (MwNftAuctionModel mwNftAuctionModel : mwNftAuctionModelList) {
            try {
                if (mwNftAuctionModel.getHighestBid().compareTo(BigDecimal.ZERO) > 0) {
                    BigInteger transferAmount = mwNftAuctionModel.getHighestBid().multiply(BigDecimal.TEN.pow(18)).toBigInteger();
                    mwToken.approve(nftAuctionContractAddress, transferAmount);
                    RemoteFunctionCall<TransactionReceipt> transactionReceiptRemoteFunctionCall = nftAuction.endAuction(new BigInteger(mwNftAuctionModel.getOrderNo()));
                    TransactionReceipt transactionReceipt = transactionReceiptRemoteFunctionCall.send();
                    boolean statusOK = transactionReceipt.isStatusOK();
                    if (!statusOK) {
                        log.info("拍卖订单号:{},执行结束失败:{}", mwNftAuctionModel.getOrderNo(),transactionReceipt.getRevertReason());
                    }
                }
            } catch (Exception e) {
                log.error("拍卖订单号:{},执行结束异常:{}", mwNftAuctionModel.getOrderNo(), e);
            }
        }
    }
```



#### 钱包登录-LoginController

1. 返回一个随机字符串
1. 前端使用MetaMask钱包生成签名
1. 后端验证签名，发放token和授权


```

    @ApiOperation("获取登录随机数")
    @GetMapping("/getNonce")
    public Result getNonce(@Validated @NotBlank(message = "address不能是空") String address) {
        Map<String, String> map = loginServer.getNonce(address);
        return ResultGenerator.genSuccessResult(map);
    }

    @ApiOperation("登录")
    @PostMapping("/login")
    public Result login(@Validated @RequestBody UserLoginDetails userLoginDetails) {
        String token = loginServer.login(userLoginDetails);
        return ResultGenerator.genSuccessResult(token);
    }
```

#### 代币转移-MwTokenController


```
    @ApiOperation("转移token")
    @PostMapping("/transfer")
    public Result transfer(@RequestBody JSONObject param) {
        String address = param.getString("address");
        BigDecimal mwAmount = param.getBigDecimal("mwAmount");
        mwTokenServer.transfer(address, mwAmount);
        return ResultGenerator.genSuccessResult();
    }
```


#### 监听合约事件-MwTokenController

1. 初始化所有合约地址
1. 初始化所有合约事件
1. 区块高度每5秒执行一次，每次扫描100：扫描范围越广，监听耗时越久，影响响应速度。区块高度要持久化（这里举例子使用redis简化），防止项目停止期间，链上有交易。


```
    public void evenLogs(EthLog ethLog) {
        if (!CollectionUtils.isEmpty(ethLog.getLogs())) {
            ethLog.getLogs().forEach(logResult -> {
                try {
                    processData((Log) logResult.get());
                } catch (Exception e) {
                    log.info("处理日志失败：{}", e);
                }
            });
        }
    }
```