LeveragedLoans1.0

• 中文版本
• English Version

⚠️Unfortunately, the Goerli testnet was dumped at March 2024. And this project is no longer available. I am trying other ways to update it into 2.0.

最新仓库: https://github.com/Chan7348/loan

中文版本

1. 项目概况

通过组合 UniswapV2 和 Compound 实现杠杆借贷功能

项目共包括 4 部分：

• core：最核心的智能合约
• subgraph：数据索引服务
• keeper：Keeper 服务
• interface：前端 UI(开发中）

2. 业务模型

杠杆借贷

用保证金做抵押，可放大杠杆

• 币本位合约：用标的资产作为保证金
• U 本位合约：用 U 作为保证金

核心功能

为了简化，只做固定的一个交易对：ETH/USDC

核心功能包括：

• 注册：注册交易账号
• 充值：充值到合约账户充当保证金
  • 充值 ETH：用于做多时
  • 充值 USDC：用于做空时
• 提现：从合约账户提取到用户钱包
  • 提现 ETH：将存款的 ETH 提取到钱包
  • 提现 USDC：将存款的 USDC 提取到钱包
• 开仓：通过 FlashSwap 和存借款完成开仓
  • 开多：存 ETH 借 USDC 实现开多
  • 开空：存 USDC 借 ETH 实现开空
• 平仓：通过还款实现平仓
  • 平多：还 USDC 实现平多
  • 平空：还 ETH 实现平空
• 限价单：当预言机价格到达设置的价格时触发开仓
  • 限价开多：当 ETH 价格回落到指定价格时触发开多
  • 限价开空：当 ETH 价格上涨到指定价格时触发开空

3. 合约实现

核心合约有两个：

• AccountRegistry
• TradingAccount

AccountRegistry

主要提供给用户创建交易账户功能

用户调用 createAccount 函数，会创建出用户自己为 owner 的交易账户合约，即 TradingAccount 合约

采用 Clone 的方式创建 TradingAccount 合约，相比用 new 的方式可以省 gas

TradingAccount

用户所有操作都通过该合约，合约主要提供的函数包括：

• depositETH: 充值 ETH，同时会存款到 Compound
• depositUSDC: 充值 USDC，同时会存款到 Compound
• withdrawETH: 提现 ETH，会从 Compound 中赎回存款并提到用户地址
• withdrawUSDC: 提现 USDC，会从 Compound 中赎回存款并提到用户地址
• openLong: 开多，即看涨 ETH
• openShort: 开空，即看跌 ETH
• closeLong: 平多
• closeShort: 平空
• limitOpenLong: 限价单开多
• limitOpenShort: 限价单开空
• cancelLimitOrder: 取消限价单
• executeLimitOrder: 执行限价单，由指定的 keeper 触发

开多

0. 开多之前需要先完成了充值 ETH
1. 调 Uniswap 进行 flashSwap 操作，用 USDC 兑换 ETH， 第一步拿到 ETH（flashSwap可以先拿到ETH再给USDC）
2. 回调到 uniswapV2Call 函数，拿到 uniswap 给出的 WETH，
3. 将 WETH 换成 ETH，然后存款到 Compound，提高抵押资产价值
4. 从 Compound 借出 USDC，并转回给到 Uniswap

开多完成后，交易账户会在 Compound 存款了 ETH，并借款了 USDC

存款的 ETH 有两部分来源，一是用户自己充值的，二是从 Uniswap 通过 FlashSwap 兑换回来的

开空

0. 开空之前需要先完成了充值 USDC
1. 调 Uniswap 进行 Swap 操作，用 WETH 兑换出 USDC
2. 回调到 uniswapV2Call 函数，该函数会先拿到 USDC
3. 将 USDC 存款到 Compound，提高抵押资产价值
4. 从 Compound 借出 ETH，转成 WETH 后转回给到 Uniswap

开空完成后，交易账户会在 Compound 存款了 USDC，并借款了 ETH

存款的 USDC 有两部分来源，一是用户自己充值的，二是从 Uniswap 通过 FlashSwap 兑换回来的

平多

平多时，需要用存款里的 ETH 兑换成 USDC 并还款

1. 根据要还款的 USDC 金额，计算出需要花费多少 ETH
2. 通过 Uniswap FlashSwap 功能先得到 USDC
3. 将 USDC 还款给 Compound
4. 从 Compound 中赎回部分 ETH
5. 将 ETH 支付给到 Uniswap

平多完成后，交易账户在 Compound 里的 ETH 存款会减少，USDC 借款也会减少

平空

平空时，需要用存款里的 USDC 兑换成 ETH 并还款

1. 根据要还款的 ETH 金额，计算出需要花费多少 USDC
2. 通过 Uniswap FlashSwap 功能先得到 ETH
3. 将 ETH 还款给 Compound
4. 从 Compound 中赎回部分 USDC
5. 将 USDC 支付给到 Uniswap

平空完成后，交易账户在 Compound 里的 USDC 存款会减少，ETH 借款也会减少

限价单

限价单不会立即成交，需等到预言机价格超过 limitPrice 之后才可执行成交

限价单无法在链上自动成交，需要指定 keeper 进行链下的价格监听，当价格满足条件后由 keeper 触发执行合约函数

4. Subgraph

核心功能包括：

• 监听每个用户的交易账号的创建
• 监听所有充值、提现、开仓、平仓、限价单等事件
• 更新每个 Position 信息
• 保存每笔交易记录
• 保存和更新每笔 LimitOrder

subgraph.yaml

定义一个 dataSource，监听 AccountRegistry 合约的 AccountCreated 事件 定义一个 template，监听 TradingAccount 合约的各种操作事件

schema.graphql

定义了几种 entity：

• Position: 当前持仓
• LimitOrder: 限价单
• DepositLog: 充值记录
• WithdrawLog: 提现记录
• OpenPositionLog: 开仓记录
• ClosePositionLog: 平仓记录

mappings

• account-registry.ts
• trading-account.ts

5. Keeper

核心功能包括：

• 实时获取最新的预言机价格
• 从 Subgraph 读取出所有满足触发条件的 LimitOrder
• 触发 executeLimitOrder

代码包结构

• main.go: 程序入口
• conf: 配置文件
• contract: 合约交互
• subgraph: 查询 Subgraph
• cron: 定时任务
• executor: 执行限价单

6. 前端 UI

核心功能主要包括：

• 注册
• 充值
• 开仓
• 查看持仓
• 关仓
• 提现

English Version

1. Project Overview

Implement the leveraged loan function by combining UniswapV2 and Compound

The project consists of 4 parts:

• core: the core smart contract
• subgraph: data indexing service
• keeper: Keeper service
• interface: front-end UI(still in development)

2. Business model

Leveraged Loan

Futures-like trading products that use margin as collateral to amplify leverage

• Coin-based contracts: use the underlying asset as margin
• U-margined contract: use U as margin

Core functions

To simplify, we only do one fixed trading pair: ETH/USDC

Core features include:

• Registration: Register a trading account
• Recharge: Recharge to the contract account to act as margin
  • Deposit ETH: used for long positions
  • Deposit USDC: used for short selling
• Withdraw: Withdraw from the contract account to the user wallet
  • Withdraw ETH: Withdraw the deposited ETH to the wallet
  • Withdraw USDC: Withdraw the deposited USDC to the wallet
• Open a position: Complete a position through FlashSwap and deposit and borrow money
  • Open long: Deposit ETH and borrow USDC to open long
  • Open Short: Deposit USDC and borrow ETH to open short
• Closing: Close the position through repayment
  • Pingduo: Return USDC to achieve Pingduo
  • Falling: Return ETH to achieve flattening
• Limit Order: Trigger the opening of a position when the oracle price reaches the set price
  • Limit price to open long: Trigger to open long when the ETH price falls back to the specified price
  • Limit Price Opening Short: Opening a short position is triggered when the price of ETH rises to the specified price

3. Contract implementation

There are two core contracts:

• AccountRegistry
• TradingAccount

AccountRegistry

Mainly provides users with the function of creating trading accounts

When the user calls the createAccount function, a Trading Account Contract of which the user is the owner will be created, that is, the TradingAccount contract

Using Clone to create the TradingAccount contract can save gas compared to using new

TradingAccount

All user operations go through this contract. The main functions provided by the contract include:

• depositETH: Deposit ETH and deposit to Compound at the same time
• depositUSDC: Deposit USDC and deposit to Compound at the same time
• withdrawETH: Withdraw ETH, the deposit will be redeemed from Compound and mentioned to the user's address
• withdrawUSDC: Withdraw USDC, the deposit will be redeemed from Compound and mentioned to the user's address
• openLong: Open long, that is, long ETH
• openShort: Open short, that is, bearish on ETH
• closeLong: Pingduo
• closeShort: close to short
• limitOpenLong: Open long limit order
• limitOpenShort: limit order to open short
• cancelLimitOrder: Cancel limit order
• executeLimitOrder: execute limit order, triggered by the specified keeper

Open long

0. You need to complete the deposit of ETH before opening a long position.
1. Call Uniswap to perform Swap operation, and use USDC to exchange for ETH
2. Call back to the uniswapV2Call function, which will first get WETH
3. Exchange WETH for ETH, then deposit to Compound to increase the value of mortgage assets
4. Lend USDC from Compound and transfer it back to Uniswap

After the long opening is completed, the trading account will deposit ETH in Compound and borrow USDC

There are two sources of deposited ETH. One is recharged by the user himself, and the other is exchanged from Uniswap through FlashSwap.

Open short

0. You need to complete the deposit of USDC before opening a short position.
1. Call Uniswap to perform Swap operation, and use WETH to exchange for USDC
2. Call back to the uniswapV2Call function, which will first get the USDC
3. Deposit USDC to Compound to increase the value of mortgage assets
4. Lend ETH from Compound, convert it into WETH and then transfer it back to Uniswap

After the short opening is completed, the trading account will deposit USDC in Compound and borrow ETH.

There are two sources of deposited USDC. One is recharged by the user himself, and the other is exchanged from Uniswap through FlashSwap.

Pingduo

In normal times, the ETH in the deposit needs to be converted into USDC and repaid.

1. Calculate how much ETH you need to spend based on the amount of USDC to be repaid
2. Get USDC first through Uniswap FlashSwap function
3. Repay USDC to Compound
4. Redeem some ETH from Compound
5. Pay ETH to Uniswap

After the leveling is completed, the ETH deposit of the trading account in Compound will be reduced, and the USDC borrowing will also be reduced.

Flat

When closing, the USDC in the deposit needs to be converted into ETH and repaid.

1. Calculate how much USDC you need to spend based on the amount of ETH to be repaid
2. Get ETH first through Uniswap FlashSwap function
3. Repay ETH to Compound
4. Redeem some USDC from Compound
5. Pay USDC to Uniswap

After the short-shoring is completed, the USDC deposits in the trading account in Compound will be reduced, and the ETH borrowing will also be reduced.

Limit order

The limit order will not be executed immediately, and the transaction can only be executed after the oracle price exceeds limitPrice

Limit orders cannot be automatically executed on the chain. You need to specify keeper to monitor prices off the chain. When the price meets the conditions, keeper will trigger the execution of the contract function.

4. Subgraph

Core features include:

• Monitor the creation of each user's trading account
• Monitor all recharge, withdrawal, position opening, closing, limit order and other events
• Update each Position information
• Save records of every transaction
• Save and update each LimitOrder

subgraph.yaml

Define a dataSource to listen to the AccountCreated event of the AccountRegistry contract Define a template to listen to various operating events of the TradingAccount contract

schema.graphql

Several entities are defined:

• Position: current position
• LimitOrder: limit order
• DepositLog: Deposit record
• WithdrawLog: withdrawal record
• OpenPositionLog: position opening record
• ClosePositionLog: position closing record

mappings

• account-registry.ts
• trading-account.ts

5. Keeper

Core features include:

• Get the latest oracle prices in real time
• Read all LimitOrders that meet the trigger conditions from Subgraph
• trigger executeLimitOrder

Code package structure

• main.go: program entry
• conf: configuration file
• contract: contract interaction
• subgraph: Query Subgraph
• cron: scheduled tasks
• executor: execute limit order

6. Front-end UI

Core functions mainly include:

• register
• top up
• Open a position
• View positions
• Close position
• withdraw