Added Tokens

migrations/2_deploy_contracts.js

@@ -0,0 +1,13 @@
+const EthSwap = artifacts.require("EthSwap");
+const Token = artifacts.require("Token");
+
+module.exports = async function(deployer) {
+
+    await deployer.deploy(Token);
+    const token=await Token.deployed();
+
+    await deployer.deploy(EthSwap,token.address);
+    const ethSwap=await EthSwap.deployed();
+
+    await token.transfer(ethSwap.address,'1000000000000000000000000')
+};

package.json

@@ -1,5 +1,5 @@
 {
-  "name": "eth-marketplace",
+  "name": "eth-swap",
   "version": "0.1.0",
   "description": "An Ethereum Marketplace",
   "author": "[email protected]",
@@ -14,6 +14,7 @@
     "chai": "4.2.0",
     "chai-as-promised": "7.1.1",
     "chai-bignumber": "3.0.0",
+    "identicon.js": "^2.3.3",
     "react": "16.8.4",
     "react-bootstrap": "1.0.0-beta.5",
     "react-dom": "16.8.4",

src/components/App.css

@@ -1 +1,4 @@
 /* Styles go here */
+.logo{
+    cursor: pointer;
+}

src/components/App.js

@@ -1,21 +1,53 @@
 import React, { Component } from 'react';
 import logo from '../logo.png';
 import './App.css';
-
+import Web3 from 'web3';
+import Navbar from './Navbar';
 class App extends Component {
+
+  async componentWillMount(){
+    await this.loadWeb3()
+    await this.loadBlockchainData()
+  }
+  async loadBlockchainData(){
+    const web3=window.web3;
+
+    const accounts=await web3.eth.getAccounts()
+
+    this.setState({account:accounts[0]})
+    const ethBalance=await web3.eth.getBalance(this.state.account)
+    this.setState({ethBalance})
+    console.log(this.state.ethBalance)
+
+  }
+
+  async loadWeb3(){
+    if (window.ethereum) {
+      window.web3 = new Web3(window.ethereum)
+      await window.ethereum.enable()
+    }
+    else if (window.web3) {
+      window.web3 = new Web3(window.web3.currentProvider)
+    }
+    else {
+      window.alert('Non-Ethereum browser detected. You should consider trying MetaMask!')
+    }
+  }
+  constructor(props) {
+    super(props)
+    this.state = {
+      account: '',
+      token: {},
+      ethSwap: {},
+      ethBalance: '0',
+      tokenBalance: '0',
+      loading: true
+    }
+  }
   render() {
     return (
       <div>
-        <nav className="navbar navbar-dark fixed-top bg-dark flex-md-nowrap p-0 shadow">
-          <a
-            className="navbar-brand col-sm-3 col-md-2 mr-0"
-            href="http://www.dappuniversity.com/bootcamp"
-            target="_blank"
-            rel="noopener noreferrer"
-          >
-            Dapp University
-          </a>
-        </nav>
+        <Navbar account={this.state.account}/>
         <div className="container-fluid mt-5">
           <div className="row">
             <main role="main" className="col-lg-12 d-flex text-center">
@@ -27,18 +59,7 @@ class App extends Component {
                 >
                   <img src={logo} className="App-logo" alt="logo" />
                 </a>
-                <h1>Dapp University Starter Kit</h1>
-                <p>
-                  Edit <code>src/components/App.js</code> and save to reload.
-                </p>
-                <a
-                  className="App-link"
-                  href="http://www.dappuniversity.com/bootcamp"
-                  target="_blank"
-                  rel="noopener noreferrer"
-                >
-                  LEARN BLOCKCHAIN <u><b>NOW! </b></u>
-                </a>
+                <h1>Hello</h1>
               </div>
             </main>
           </div>

src/components/Navbar.js

@@ -0,0 +1,41 @@
+import React, { Component } from 'react'
+import Identicon from 'identicon.js';
+
+class Navbar extends Component {
+
+  render() {
+    return (
+      <nav className="navbar navbar-dark fixed-top bg-dark flex-md-nowrap p-0 shadow">
+        <a
+          className="navbar-brand col-sm-3 col-md-2 mr-0"
+          href="http://www.dappuniversity.com/bootcamp"
+          target="_blank"
+          rel="noopener noreferrer"
+        >
+          EthSwap
+        </a>
+        <ul className="navbar-nav px-3">
+          <li className="nav-item text-nowrap d-none d-sm-none d-sm-block">
+            <small className="text-secondary">
+              <small id="account">{this.props.account}</small>
+            </small>
+
+            { this.props.account
+              ? <img
+                className="ml-2 logo"
+                width='30'
+                height='30'
+                src={`data:image/png;base64,${new Identicon(this.props.account, 30).toString()}`}
+                alt=""
+              />
+              : <span></span>
+            }
+
+          </li>
+        </ul>
+        </nav>
+  );
+}
+}
+
+export default Navbar

src/contracts/EthSwap.sol

@@ -0,0 +1,48 @@
+pragma solidity ^0.5.0;
+
+import "./Token.sol";
+
+contract EthSwap{
+    string public name="EthSwap Instant Exchange";
+    Token public token;
+    uint public rate=100;
+
+    event TokenPurchased(
+        address account,
+        address token,
+        uint amount,
+        uint rate
+    );
+    event TokensSold(
+        address account,
+        address token,
+        uint amount,
+        uint rate
+    );
+
+    constructor (Token _token) public {
+        token = _token;
+
+    }
+
+    function buyTokens() public payable{
+        uint tokenAmount = msg.value * rate;
+
+        require(token.balanceOf(address(this)) >= tokenAmount);
+        token.transfer(msg.sender,tokenAmount);
+
+        emit TokenPurchased(msg.sender,address(token), tokenAmount, rate);
+    }
+    function sellTokens(uint _amount) public {
+        require(token.balanceOf(msg.sender) >= _amount);
+
+        uint etherAmount=_amount/rate;
+
+        require(address(this).balance >=etherAmount);
+
+        token.transferFrom(msg.sender, address(this), _amount);
+        msg.sender.transfer(etherAmount);
+
+       emit TokensSold(msg.sender,address(token), _amount, rate);
+    }
+}

src/contracts/Token.sol

@@ -0,0 +1,53 @@
+pragma solidity ^0.5.0;
+
+contract Token {
+    string  public name = "DApp Token";
+    string  public symbol = "DAPP";
+    uint256 public totalSupply = 1000000000000000000000000; // 1 million tokens
+    uint8   public decimals = 18;
+
+    //Wei Smallest Eth tokens
+
+    event Transfer(
+        address indexed _from,
+        address indexed _to,
+        uint256 _value
+    );
+
+    event Approval(
+        address indexed _owner,
+        address indexed _spender,
+        uint256 _value
+    );
+
+    mapping(address => uint256) public balanceOf;
+    mapping(address => mapping(address => uint256)) public allowance;
+
+    constructor() public {
+        balanceOf[msg.sender] = totalSupply;
+    }
+
+    function transfer(address _to, uint256 _value) public returns (bool success) {
+        require(balanceOf[msg.sender] >= _value);
+        balanceOf[msg.sender] -= _value;
+        balanceOf[_to] += _value;
+        emit Transfer(msg.sender, _to, _value);
+        return true;
+    }
+
+    function approve(address _spender, uint256 _value) public returns (bool success) {
+        allowance[msg.sender][_spender] = _value;
+        emit Approval(msg.sender, _spender, _value);
+        return true;
+    }
+
+    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
+        require(_value <= balanceOf[_from]);
+        require(_value <= allowance[_from][msg.sender]);
+        balanceOf[_from] -= _value;
+        balanceOf[_to] += _value;
+        allowance[_from][msg.sender] -= _value;
+        emit Transfer(_from, _to, _value);
+        return true;
+    }
+}

test/EthSwap.test.js

@@ -0,0 +1,92 @@
+const { assert } = require('chai');
+
+
+
+const EthSwap = artifacts.require("EthSwap");
+const Token = artifacts.require("Token");
+
+require('chai')
+    .use(require('chai-as-promised'))
+    .should();
+
+    function tokens(n) {
+        return web3.utils.toWei(n, 'ether');
+    }
+
+contract('EthSwap',([deployer,investor])=>{
+    let token,ethSwap
+    before(async ()=>{
+        token = await Token.new()
+        ethSwap = await EthSwap.new(token.address)
+        await token.transfer(ethSwap.address,tokens('1000000'))
+    })
+
+    describe('Token deployment',async()=>{
+        it('contract has a name',async()=>{
+            const name=await token.name()
+            assert.equal(name,'DApp Token')
+        })
+    })
+    describe('EthSwap deployment',async()=>{
+        it('contract has a name',async()=>{
+            const name=await ethSwap.name()
+            assert.equal(name,'EthSwap Instant Exchange')
+        })
+
+        it('contract has tokens',async()=>{
+            let balance=await token.balanceOf(ethSwap.address)
+            assert.equal(balance.toString(),tokens('1000000'))
+        })
+    })
+
+    describe('buy tokens',async()=>{
+        let result
+
+        before(async () => {
+          // Purchase tokens before each example
+          result = await ethSwap.buyTokens({ from: investor, value: web3.utils.toWei('1', 'ether')})
+        })
+        it('Allows user to buy tokens for a fixed eth price',async()=>{
+            let investorBalance=await token.balanceOf(investor)
+            assert.equal(investorBalance.toString(),tokens('100'))
+
+            let ethSwapBalance=await token.balanceOf(ethSwap.address)
+            assert.equal(ethSwapBalance.toString(),tokens('999900'))
+            ethSwapBalance=await web3.eth.getBalance(ethSwap.address)
+            assert.equal(ethSwapBalance.toString(),web3.utils.toWei('1','Ether'))
+
+            const event = result.logs[0].args
+            assert.equal(event.account, investor)
+            assert.equal(event.token, token.address)
+            assert.equal(event.amount.toString(), tokens('100').toString())
+            assert.equal(event.rate.toString(), '100')
+
+        })
+    })
+
+    describe('sellTokens()',async()=>{
+        let result
+        before(async()=>{
+            await token.approve(ethSwap.address,tokens('100'),{from:investor})
+            result = await ethSwap.sellTokens(tokens('100'),{from:investor})
+        })
+        it('allows user to sell tokens',async ()=>{
+            let investorBalance=await token.balanceOf(investor)
+            assert.equal(investorBalance.toString(),tokens('0'))
+
+            let ethSwapBalance
+            ethSwapBalance = await token.balanceOf(ethSwap.address)
+            assert.equal(ethSwapBalance.toString(), tokens('1000000'))
+            ethSwapBalance = await web3.eth.getBalance(ethSwap.address)
+            assert.equal(ethSwapBalance.toString(), web3.utils.toWei('0', 'Ether'))
+
+            const event = result.logs[0].args
+            assert.equal(event.account, investor)
+            assert.equal(event.token, token.address)
+            assert.equal(event.amount.toString(), tokens('100').toString())
+            assert.equal(event.rate.toString(), '100')
+
+            await ethSwap.sellTokens(tokens('500'), { from: investor }).should.be.rejected;
+        })
+    })
+})