Stub of solidity contracts

ethereum/.gitignore

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+node_modules
+.env
+
+# Hardhat files
+/cache
+/artifacts
+
+# TypeChain files
+/typechain
+/typechain-types
+
+# solidity-coverage files
+/coverage
+/coverage.json

ethereum/contracts/Availability.sol

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+// SPDX-License-Identifier: Unlicense
+pragma solidity ^0.8.24;
+
+import "./ReputationHolder.sol";
+
+contract Availability is ReputationHolder {}

ethereum/contracts/DAO.sol

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+// SPDX-License-Identifier: Unlicense
+pragma solidity ^0.8.24;
+
+import {ERC721} from "@openzeppelin/contracts/token/ERC721/ERC721.sol";
+import "./ReputationHolder.sol";
+
+/// This contract must manage validation pools and reputation,
+/// because otherwise there's no way to enforce appropriate permissions on
+/// transfer of value between reputation NFTs.
+contract DAO is ERC721("Reputation", "REP"), ReputationHolder {
+    mapping(uint256 tokenId => uint256) _tokenValues;
+    uint256 _nextTokenId;
+
+    /// Inspect the value of a given reputation NFT
+    function valueOf(uint256 tokenId) public view returns (uint256 value) {
+        value = _tokenValues[tokenId];
+    }
+
+    /// Internal function to mint a new reputation NFT
+    function mint() internal returns (uint256 tokenId) {
+        // Generate a new (sequential) ID for the token
+        tokenId = _nextTokenId++;
+        // Mint the token, initially to be owned by the current contract.
+        _mint(address(this), tokenId);
+    }
+
+    /// Internal function to transfer value from one reputation token to another
+    function transferValueFrom(
+        uint256 fromTokenId,
+        uint256 toTokenId,
+        uint256 amount
+    ) internal {
+        require(amount >= 0);
+        require(valueOf(fromTokenId) >= amount);
+        _tokenValues[fromTokenId] -= amount;
+        _tokenValues[toTokenId] += amount;
+    }
+}

ethereum/contracts/Lock.sol

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+// SPDX-License-Identifier: Unlicense
+pragma solidity ^0.8.24;
+
+// Uncomment this line to use console.log
+// import "hardhat/console.sol";
+
+contract Lock {
+    uint public unlockTime;
+    address payable public owner;
+
+    event Withdrawal(uint amount, uint when);
+
+    constructor(uint _unlockTime) payable {
+        require(
+            block.timestamp < _unlockTime,
+            "Unlock time should be in the future"
+        );
+
+        unlockTime = _unlockTime;
+        owner = payable(msg.sender);
+    }
+
+    function withdraw() public {
+        // Uncomment this line, and the import of "hardhat/console.sol", to print a log in your terminal
+        // console.log("Unlock time is %o and block timestamp is %o", unlockTime, block.timestamp);
+
+        require(block.timestamp >= unlockTime, "You can't withdraw yet");
+        require(msg.sender == owner, "You aren't the owner");
+
+        emit Withdrawal(address(this).balance, block.timestamp);
+
+        owner.transfer(address(this).balance);
+    }
+}

ethereum/contracts/ReputationHolder.sol

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+// SPDX-License-Identifier: Unlicense
+pragma solidity ^0.8.24;
+
+import {ERC721Holder} from "@openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol";
+
+abstract contract ReputationHolder is ERC721Holder {}

ethereum/contracts/Work1.sol

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+// SPDX-License-Identifier: Unlicense
+pragma solidity ^0.8.24;
+
+import {IERC721Receiver} from "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol";
+import "./DAO.sol";
+import "./ReputationHolder.sol";
+
+struct AvailabilityStake {
+    address worker;
+    uint256 tokenId;
+    uint256 amount;
+    bool assigned;
+}
+
+enum WorkStatus {
+    Requested,
+    EvidenceSubmitted,
+    ApprovalSubmitted,
+    Complete
+}
+
+struct WorkRequest {
+    address customer;
+    uint256 fee;
+    WorkStatus status;
+    uint stakeIndex;
+    bool approval;
+}
+
+contract Work1 is IERC721Receiver {
+    DAO dao;
+    uint public immutable price;
+    mapping(uint => AvailabilityStake) stakes;
+    uint stakeCount;
+    mapping(uint => WorkRequest) requests;
+    uint requestCount;
+
+    event WorkAssigned(address worker, uint requestIndex);
+
+    constructor(DAO dao_, uint price_) {
+        dao = dao_;
+        price = price_;
+    }
+
+    /// Accept availability stakes as reputation token transfer
+    function onERC721Received(
+        address,
+        address from,
+        uint256 tokenId,
+        bytes calldata
+    ) external override returns (bytes4) {
+        AvailabilityStake storage stake = stakes[stakeCount++];
+        stake.worker = from;
+        stake.tokenId = tokenId;
+        stake.amount = dao.valueOf(tokenId);
+        return IERC721Receiver.onERC721Received.selector;
+    }
+
+    /// Select a worker randomly from among the available workers, weighted by amount staked
+    function randomWeightedSelection() internal view returns (uint) {
+        uint totalStakes;
+        for (uint i = 0; i < stakeCount; i++) {
+            if (stakes[i].assigned) continue;
+            totalStakes += stakes[i].amount;
+        }
+        uint select = block.prevrandao % totalStakes;
+        uint acc;
+        for (uint i = 0; i < stakeCount; i++) {
+            if (stakes[i].assigned) continue;
+            acc += stakes[i].amount;
+            if (acc >= select) return i;
+        }
+        revert("Failed to select worker");
+    }
+
+    /// Assign a random available worker
+    function assignWork(uint requestIndex) internal returns (uint stakeIndex) {
+        stakeIndex = randomWeightedSelection();
+        AvailabilityStake storage stake = stakes[stakeIndex];
+        stake.assigned = true;
+        emit WorkAssigned(stake.worker, requestIndex);
+    }
+
+    /// Accept work request with fee
+    function requestWork() external payable {
+        require(msg.value >= price, "Insufficient fee");
+        uint requestIndex = requestCount++;
+        WorkRequest storage request = requests[requestIndex];
+        request.customer = msg.sender;
+        request.stakeIndex = assignWork(requestIndex);
+    }
+
+    /// Accept work evidence from worker
+    function submitWorkEvidence(uint requestIndex) external {
+        WorkRequest storage request = requests[requestIndex];
+        require(request.status == WorkStatus.Requested);
+        AvailabilityStake storage stake = stakes[request.stakeIndex];
+        require(stake.worker == msg.sender);
+        request.status = WorkStatus.EvidenceSubmitted;
+    }
+
+    /// Accept work approval/disapproval from customer
+    function submitWorkApproval(uint requestIndex, bool approval) external {
+        WorkRequest storage request = requests[requestIndex];
+        require(request.status == WorkStatus.EvidenceSubmitted);
+        request.status = WorkStatus.ApprovalSubmitted;
+        request.approval = approval;
+        // TODO: Initiate validation pool
+    }
+}

ethereum/hardhat.config.js

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+require("@nomicfoundation/hardhat-toolbox");
+
+/** @type import('hardhat/config').HardhatUserConfig */
+module.exports = {
+  solidity: "0.8.24",
+};

ethereum/package.json

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+{
+  "name": "dgf-prototype",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "author": "",
+  "license": "ISC",
+  "devDependencies": {
+    "@nomicfoundation/hardhat-toolbox": "^4.0.0",
+    "hardhat": "^2.20.1",
+    "prettier": "^3.2.5",
+    "prettier-plugin-solidity": "^1.3.1"
+  },
+  "dependencies": {
+    "@openzeppelin/contracts": "^5.0.2"
+  }
+}

ethereum/scripts/deploy.js

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+// We require the Hardhat Runtime Environment explicitly here. This is optional
+// but useful for running the script in a standalone fashion through `node <script>`.
+//
+// You can also run a script with `npx hardhat run <script>`. If you do that, Hardhat
+// will compile your contracts, add the Hardhat Runtime Environment's members to the
+// global scope, and execute the script.
+const hre = require("hardhat");
+
+async function main() {
+  const currentTimestampInSeconds = Math.round(Date.now() / 1000);
+  const unlockTime = currentTimestampInSeconds + 60;
+
+  const lockedAmount = hre.ethers.parseEther("0.001");
+
+  const lock = await hre.ethers.deployContract("Lock", [unlockTime], {
+    value: lockedAmount,
+  });
+
+  await lock.waitForDeployment();
+
+  console.log(
+    `Lock with ${ethers.formatEther(
+      lockedAmount
+    )}ETH and unlock timestamp ${unlockTime} deployed to ${lock.target}`
+  );
+}
+
+// We recommend this pattern to be able to use async/await everywhere
+// and properly handle errors.
+main().catch((error) => {
+  console.error(error);
+  process.exitCode = 1;
+});

ethereum/test/Lock.js

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+const {
+  time,
+  loadFixture,
+} = require("@nomicfoundation/hardhat-toolbox/network-helpers");
+const { anyValue } = require("@nomicfoundation/hardhat-chai-matchers/withArgs");
+const { expect } = require("chai");
+
+describe("Lock", function () {
+  // We define a fixture to reuse the same setup in every test.
+  // We use loadFixture to run this setup once, snapshot that state,
+  // and reset Hardhat Network to that snapshot in every test.
+  async function deployOneYearLockFixture() {
+    const ONE_YEAR_IN_SECS = 365 * 24 * 60 * 60;
+    const ONE_GWEI = 1_000_000_000;
+
+    const lockedAmount = ONE_GWEI;
+    const unlockTime = (await time.latest()) + ONE_YEAR_IN_SECS;
+
+    // Contracts are deployed using the first signer/account by default
+    const [owner, otherAccount] = await ethers.getSigners();
+
+    const Lock = await ethers.getContractFactory("Lock");
+    const lock = await Lock.deploy(unlockTime, { value: lockedAmount });
+
+    return { lock, unlockTime, lockedAmount, owner, otherAccount };
+  }
+
+  describe("Deployment", function () {
+    it("Should set the right unlockTime", async function () {
+      const { lock, unlockTime } = await loadFixture(deployOneYearLockFixture);
+
+      expect(await lock.unlockTime()).to.equal(unlockTime);
+    });
+
+    it("Should set the right owner", async function () {
+      const { lock, owner } = await loadFixture(deployOneYearLockFixture);
+
+      expect(await lock.owner()).to.equal(owner.address);
+    });
+
+    it("Should receive and store the funds to lock", async function () {
+      const { lock, lockedAmount } = await loadFixture(
+        deployOneYearLockFixture
+      );
+
+      expect(await ethers.provider.getBalance(lock.target)).to.equal(
+        lockedAmount
+      );
+    });
+
+    it("Should fail if the unlockTime is not in the future", async function () {
+      // We don't use the fixture here because we want a different deployment
+      const latestTime = await time.latest();
+      const Lock = await ethers.getContractFactory("Lock");
+      await expect(Lock.deploy(latestTime, { value: 1 })).to.be.revertedWith(
+        "Unlock time should be in the future"
+      );
+    });
+  });
+
+  describe("Withdrawals", function () {
+    describe("Validations", function () {
+      it("Should revert with the right error if called too soon", async function () {
+        const { lock } = await loadFixture(deployOneYearLockFixture);
+
+        await expect(lock.withdraw()).to.be.revertedWith(
+          "You can't withdraw yet"
+        );
+      });
+
+      it("Should revert with the right error if called from another account", async function () {
+        const { lock, unlockTime, otherAccount } = await loadFixture(
+          deployOneYearLockFixture
+        );
+
+        // We can increase the time in Hardhat Network
+        await time.increaseTo(unlockTime);
+
+        // We use lock.connect() to send a transaction from another account
+        await expect(lock.connect(otherAccount).withdraw()).to.be.revertedWith(
+          "You aren't the owner"
+        );
+      });
+
+      it("Shouldn't fail if the unlockTime has arrived and the owner calls it", async function () {
+        const { lock, unlockTime } = await loadFixture(
+          deployOneYearLockFixture
+        );
+
+        // Transactions are sent using the first signer by default
+        await time.increaseTo(unlockTime);
+
+        await expect(lock.withdraw()).not.to.be.reverted;
+      });
+    });
+
+    describe("Events", function () {
+      it("Should emit an event on withdrawals", async function () {
+        const { lock, unlockTime, lockedAmount } = await loadFixture(
+          deployOneYearLockFixture
+        );
+
+        await time.increaseTo(unlockTime);
+
+        await expect(lock.withdraw())
+          .to.emit(lock, "Withdrawal")
+          .withArgs(lockedAmount, anyValue); // We accept any value as `when` arg
+      });
+    });
+
+    describe("Transfers", function () {
+      it("Should transfer the funds to the owner", async function () {
+        const { lock, unlockTime, lockedAmount, owner } = await loadFixture(
+          deployOneYearLockFixture
+        );
+
+        await time.increaseTo(unlockTime);
+
+        await expect(lock.withdraw()).to.changeEtherBalances(
+          [owner, lock],
+          [lockedAmount, -lockedAmount]
+        );
+      });
+    });
+  });
+});