2022年11月 - 区块链中文技术社区

部署仅在技术方案调研角度，客观测试，仅作记录
先草稿记录，后续再做整理

现有主网或者测试网

对于现有主网或者测试网节点的加入可参考
https://github.com/bttcprotocol/launch
环境进行运行，注意下脚本默认运行目录在home目录，可以通过执行--home 参数进行相应变更。

私链搭建

一方面为了技术调研，目前需要做的是搭建一个完整的BTTC私链
主要分为三部分进行测试部署

1. BTTC生产层

github: https://github.com/bttcprotocol/bttc.git
对于bttc，是从go-ethereum修改而来，简单来说这一层负责区块的生产
https://doc.bt.io/zh-Hans/docs/basics/bttc-basics/bttc-pos-architecture#bttc-%E5%8C%BA%E5%9D%97%E7%94%9F%E4%BA%A7%E8%80%85%E5%B1%82

2. Delivery层

github: https://github.com/bttcprotocol/delivery
负责区块验证、Bttc层区块生产者的选择、代表Bttc层状态检查点的验证和提交,以及其他各种责任。
https://doc.bt.io/zh-Hans/docs/basics/bttc-basics/bttc-pos-architecture#delivery-pos%E5%B1%82

3. 部署在TRON网络上的质押管理合约

Staking合约

从出块共识来说

简单来说，相对其他go-ethereum修改的pos链，Bittorrent-Chain的选举是在TRON网络上的质押管理合约中的，然后通过Delivery层进行数据的验证者的排名，然后bttc更新验证者排名时从Delivery层获取，作为下次出块周期的验证者列表。

测试私链

根据bttc的三层实现，计划私链的启动顺序如下

仅bttc层，完成私链搭建
来验证bttc层genesis参数，初始化周期验证者的选择逻辑，以及一些启动参数的测试
TRON测试网络部署相关合约
来验证合约的编译和部署过程，为下一步与Delivery层结合做准备
bttc + Delivery层 + TRON网络上的质押管理合约
整体测试

bttc层私链搭建

先使用官方的测试例子，测一下
https://github.com/bttcprotocol/contracts/tree/stake/test-blockchain
从中找到genesis模板
https://github.com/bttcprotocol/contracts/blob/stake/test-blockchain/genesis.json.template
https://github.com/bttcprotocol/bttc/blob/master/tests/bor/testdata/genesis.json

从确认初始化验证者加入方式，重点关注validatorContract合约，对应地址0x0000000000000000000000000000000000001000
常规的初始化验证者的加入，时添加到extraData或者其他数组数据设置，从demo没看到对用的数据，然后调试整体代码

调试整体代码

miner->commitNewWork->commit->FinalizeAndAssemble->(headerNumber%c.config.Sprint == 0)->checkAndCommitSpan->needToCommitSpan->fetchAndCommitSpan->WithoutHeimdall
getNextHeimdallSpanForTest / HeimdallClient.FetchWithRetry

发现bttc层溜了一个测试开关，

--bor.withoutheimdall

启动参数添加后，进入Test模式，也就是bttc下一周期（genesis配置的Sprint，默认64）的验证者列表会执行getNextHeimdallSpanForTest继续从合约中初始数据中获取

GetCurrentValidators->getBorValidators

修改初始化验证者地址

默认的验证者地址是在getInitialValidators设置的
https://github.com/bttcprotocol/genesis-contracts/blob/63b72f1ca9a20064d4e700b026ca631335717b4b/contracts/BorValidatorSet.sol#L216

  /// Get current validator set (last enacted or initial if no changes ever made) with current stake.
  function getInitialValidators() public view returns (address[] memory, uint256[] memory) {
    address[] memory addrs = new address[](3);
    addrs[0] = 0xfA841eAAcf03598bAadF0266eF6097C654DE5465;
    addrs[1] = 0x80CFb197Be875eE45294AC31406E6483e3eAb02E;
    addrs[2] = 0x0aB3ab4542ED5FA2A67B2B8DAbC82C42162853A6;
    uint256[] memory powers = new uint256[](3);
    powers[0] = 1;
    powers[1] = 1;
    powers[2] = 1;
    return (addrs, powers);
  }

需要修改成我们自己的私链初始化验证者地址

编译系统合约

Clone code

git clone https://github.com/bttcprotocol/genesis-contracts.git

修改我们私链的初始化验证者地址
https://github.com/bttcprotocol/genesis-contracts/blob/master/validators.json

[
{
 "address": "0xfA841eAAcf03598bAadF0266eF6097C654DE5465",
 "stake": 1,
 "balance": 300000000
},
{
 "address": "0x80CFb197Be875eE45294AC31406E6483e3eAb02E",
 "stake": 1,
 "balance": 300000000
},
{
 "address": "0x0aB3ab4542ED5FA2A67B2B8DAbC82C42162853A6",
 "stake": 1,
 "balance": 300000000
}
]

生成我们私链的合约

node generate-borvalidatorset.js --bttc-chain-id 9527 --delivery-chain-id delivery-9527

Install dependencies and submodules

$ npm install
$ git submodule init
$ git submodule update

Compile Bttc contracts
切记！！node需要v11版本！
```
nvm install v11
nvm use v11
```
下面truffle:compile依赖docker
https://desktop.docker.com/mac/main/amd64/Docker.dmg?utm_source=docker&utm_medium=webreferral&utm_campaign=docs-driven-download-mac-amd64
```
$ cd bttc-contracts
$ npm install
$ node scripts/process-templates.js --bttc-chain-id <bttc-chain-id> // 9527
$ npm run truffle:compile
$ cd ..
```

附加

如果不加开关将会

--bor.heimdall "http://localhost:1317"

第一轮（sprint 64）验证者 Signer 是从系统合约getBorValidators，获取的固定的信息，
查询此期间block的miner为
0x0000000000000000000000000000000000000000
下一周期开始与delivery层进行数据获取

参考：https://doc.bt.io/zh-Hans/docs/basics/bttc-basics/bttc-pos-architecture

参考

项目官网：https://bt.io/
github: https://github.com/bttcprotocol
官方文档：https://doc.bt.io/zh-Hans/

func (w *worker) commitNewWork(interrupt *int32, noempty bool, timestamp int64) { // 创建区块头 header := &types.Header{ ParentHash: parent.Hash(), Number: num.Add(num, common.Big1), // 计算GasLimit GasLimit: core.CalcGasLimit(parent, w.config.GasFloor, w.config.GasCeil), Extra: w.extra, Time: uint64(timestamp), } // 从交易池中读取交易 pending, err := w.eth.TxPool().Pending() if err != nil { log.Error("Failed to fetch pending transactions", "err", err) return } // Short circuit if there is no available pending transactions if len(pending) == 0 { w.updateSnapshot() return } // Split the pending transactions into locals and remotes localTxs, remoteTxs := make(map[common.Address]types.Transactions), pending for _, account := range w.eth.TxPool().Locals() { if txs := remoteTxs[account]; len(txs) > 0 { delete(remoteTxs, account) localTxs[account] = txs } } if len(localTxs) > 0 { txs := types.NewTransactionsByPriceAndNonce(w.current.signer, localTxs) if w.commitTransactions(txs, w.coinbase, interrupt) { return } } if len(remoteTxs) > 0 { txs := types.NewTransactionsByPriceAndNonce(w.current.signer, remoteTxs) if w.commitTransactions(txs, w.coinbase, interrupt) { return } } }

func (w *worker) commitTransactions(txs *types.TransactionsByPriceAndNonce, coinbase common.Address, interrupt *int32) bool { // 将区块头中的GasLimit赋值给gasPool if w.current.gasPool == nil { w.current.gasPool = new(core.GasPool).AddGas(w.current.header.GasLimit) } // 循环判断所有交易 for { // gasPool中的gas小于21000是跳出循环 if w.current.gasPool.Gas() < params.TxGas { log.Trace("Not enough gas for further transactions", "have", w.current.gasPool, "want", params.TxGas) break } // 按照交易gas从大到小的顺序获取下一个交易 tx := txs.Peek() // 没有交易后跳出循环 if tx == nil { break } // 提交交易 logs, err := w.commitTransaction(tx, coinbase) } }

// CalcGasLimit computes the gas limit of the next block after parent. It aims // to keep the baseline gas above the provided floor, and increase it towards the // ceil if the blocks are full. If the ceil is exceeded, it will always decrease // the gas allowance. func CalcGasLimit(parent *types.Block, gasFloor, gasCeil uint64) uint64 { // contrib = (parentGasUsed * 3 / 2) / 1024 contrib := (parent.GasUsed() + parent.GasUsed()/2) / params.GasLimitBoundDivisor // decay = parentGasLimit / 1024 -1 decay := parent.GasLimit()/params.GasLimitBoundDivisor - 1 /* strategy: gasLimit of block-to-mine is set based on parent's gasUsed value. if parentGasUsed > parentGasLimit * (2/3) then we increase it, otherwise lower it (or leave it unchanged if it's right at that usage) the amount increased/decreased depends on how far away from parentGasLimit * (2/3) parentGasUsed is. */ limit := parent.GasLimit() - decay + contrib if limit < params.MinGasLimit { limit = params.MinGasLimit } // If we're outside our allowed gas range, we try to hone towards them if limit < gasFloor { limit = parent.GasLimit() + decay if limit > gasFloor { limit = gasFloor } } else if limit > gasCeil { limit = parent.GasLimit() - decay if limit < gasCeil { limit = gasCeil } } return limit }

Bittorrent-Chain私链搭建 - BTTC层（一）