Deploys Maker contracts to a Truffle development network

Convert Ether to Dai.sol

OasisDEXInterface oasisDex;
WETHInterface weth;
ERC20 dai;

function createStudyWithDaiExchange(
  string _name,
  string _desc,
  string _citation,
  uint64 _expiresOn,
  string _publicKey,
  DataDefinition _dataDefinition,
  string _consentHash,
  uint _minBuyAmt) public payable
{
  // Convert the ETH to Wrapped ETH (WETH) for trading
  weth.deposit.value(msg.value)();
  // Give max allowance to oasisdex to spend weth
  if (weth.allowance(this, oasisDex) < msg.value) {
  weth.approve(oasisDex, uint(-1));
  }
  // Sell the WETH for a minBuyAmt of DAI
  uint daiAmt = oasisDex.sellAllAmount(weth, msg.value, dai, _minBuyAmt);

  // Now our contract owns daiAmount of Dai.
  // <create the study with that amount of Dai as payment>
}

DeployMaker.js

// SPDX-License-Identifier: AGPL-3.0+
const OasisDEX = artifacts.require("./maker/MatchingMarket.sol");
const FakeDAI = artifacts.require("./maker/FakeDAI.sol");
const WETH = artifacts.require("./maker/WETH9_.sol");

const Web3 = require("web3");

const web3 = new Web3();

// never close
const OASIS_DEX_CLOSE_TIME = 1000000000000000;
const WETH_DEPOSIT_AMOUNT = web3.utils.toWei("5", "ether");
const DAI_PER_WETH = 400;
const DAI_DEPOSIT_AMOUNT = 1000 * 10 ** 18;

module.exports = async (deployer, network) => {
  if (network !== "develop") {
    return; // Contracts already deployed
  }

  // Deploy all contracts
  await Promise.all([
    deployer.deploy(OasisDEX, OASIS_DEX_CLOSE_TIME),
    deployer.deploy(WETH),
    deployer.deploy(FakeDAI)
  ]);

  const [oasisDex, weth, fdai] = await Promise.all([
    OasisDEX.deployed(),
    WETH.deployed(),
    FakeDAI.deployed()
  ]);
  await oasisDex.addTokenPairWhitelist(WETH.address, FakeDAI.address);

  console.log("Setting up WETH -> DAI trading site...");

  await weth.deposit({ value: WETH_DEPOSIT_AMOUNT });
  await weth.approve(OasisDEX.address, WETH_DEPOSIT_AMOUNT);
  await oasisDex.offer(
    WETH_DEPOSIT_AMOUNT,
    WETH.address,
    WETH_DEPOSIT_AMOUNT * DAI_PER_WETH,
    FakeDAI.address,
    0
  );

  console.log("Setting up DAI -> WETH trading side...");

  // Set up DAI -> WETH trade side
  await fdai.mint(await fdai.owner(), DAI_DEPOSIT_AMOUNT);
  await fdai.approve(OasisDEX.address, DAI_DEPOSIT_AMOUNT);

  await oasisDex.offer(
    DAI_DEPOSIT_AMOUNT,
    FakeDAI.address,
    // TODO For some reason this throws an Internal JSON-RPC error when you
    // make this < 0.005
    DAI_DEPOSIT_AMOUNT * 0.005,
    WETH.address,
    0
  );
};

DeployMaker_1.js

const OasisDEX = artifacts.require("./maker/MatchingMarket.sol");
const FakeDAI = artifacts.require("./maker/FakeDAI.sol");
const WETH = artifacts.require("./maker/WETH9_.sol");

const Web3 = require("web3");

const web3 = new Web3();

// never close
const OASIS_DEX_CLOSE_TIME = 1000000000000000;
const WETH_DEPOSIT_AMOUNT = web3.utils.toWei("5", "ether");
const DAI_PER_WETH = 400;
const DAI_DEPOSIT_AMOUNT = 1000 * 10 ** 18;

module.exports = async (deployer, network) => {
  if (network !== "develop") {
    return; // Contracts already deployed
  }

  // Deploy all contracts
  await Promise.all([
    deployer.deploy(OasisDEX, OASIS_DEX_CLOSE_TIME),
    deployer.deploy(WETH),
    deployer.deploy(FakeDAI)
  ]);

  const [oasisDex, weth, fdai] = await Promise.all([
    OasisDEX.deployed(),
    WETH.deployed(),
    FakeDAI.deployed()
  ]);

DeployMaker_2.js

await oasisDex.addTokenPairWhitelist(WETH.address, FakeDAI.address);

DeployMaker_3.js

  console.log("Setting up WETH -> DAI trading site...");

  await weth.deposit({ value: WETH_DEPOSIT_AMOUNT });
  await weth.approve(OasisDEX.address, WETH_DEPOSIT_AMOUNT);
  await oasisDex.offer(
    WETH_DEPOSIT_AMOUNT,
    WETH.address,
    WETH_DEPOSIT_AMOUNT * DAI_PER_WETH,
    FakeDAI.address,
    0
  );

  console.log("Setting up DAI -> WETH trading side...");

  // Set up DAI -> WETH trade side
  await fdai.mint(await fdai.owner(), DAI_DEPOSIT_AMOUNT);
  await fdai.approve(OasisDEX.address, DAI_DEPOSIT_AMOUNT);

  await oasisDex.offer(
    DAI_DEPOSIT_AMOUNT,
    FakeDAI.address,
    // TODO For some reason this throws an Internal JSON-RPC error when you
    // make this < 0.005
    DAI_DEPOSIT_AMOUNT * 0.005,
    WETH.address,
    0
  );

ERC20 createStudy.sol

Study[] studies; ERC20 dai;

constructor(address _dai) {
  dai = ERC20(_dai);
}
function createStudy(
  string _name,
  string _desc,
  string _citation,
  uint64 _expiresOn,
  string _publicKey,
  DataDefinition _dataDefinition,
  string _consentHash,
  uint256 _paymentPool) public
{
  require(_paymentPool != 0);
  require(dai.transferFrom(msg.sender, this, _paymentPool));
  Study memory newStudy;
  newStudy.paymentPool = msg.value;
  studies.push(newStudy);
}

Get buy amount.js

await oasisDexMarket.functions.getBuyAmount(
  await getDeployedAddress(Contract.DAI, getState().web3.network),
  await getDeployedAddress(Contract.WETH, getState().web3.network),
  paymentPool // In Ether
);

Original createStudy.sol

Study[] studies;

function createStudy(
  string _name,
  string _desc,
  string _citation,
  uint64 _expiresOn,
  string _publicKey,
  DataDefinition _dataDefinition,
  string _consentHash) public payable
{
  require(msg.value >= 0.1 ether);
  Study memory newStudy;
  newStudy.paymentPool = msg.value;
  studies.push(newStudy);
}

Awesome stuff here, just curious, do you have a FakeDai.sol contract anywhere?