9 张伟 第五+第六次作业

Lesson2/assignment/yours.sol

@@ -279,4 +279,4 @@ execution cost   930 gas
 transaction cost   22202 gas 
 execution cost   930 gas
 
-//gas 不变了，因为calculateRunway现在只是做一个除法
+//gas 不变了，因为calculateRunway现在只是做一个除法

Lesson3/README.md

@@ -0,0 +1,16 @@
+## 硅谷live以太坊智能合约频道官方地址
+
+### 第三课《智能合约后端优化和产品化》
+
+目录结构
+  <br/>|
+  <br/>|--orgin 课程初始代码
+  <br/>|
+  <br/>|--assignment 课程作业提交代码
+<br/> 
+### 本节知识点
+第3课：智能合约后端优化和产品化
+- 如何通过数据结构优化降低合约执行成本
+- 合约的继承
+- 巧用modifier
+- 以太坊函数库的使用和基本介绍

Lesson3/assignment/README.md

@@ -0,0 +1,14 @@
+## 硅谷live以太坊智能合约 第三课作业
+这里是同学提交作业的目录
+
+### 第三课：课后作业
+- 第一题：完成今天所开发的合约产品化内容，使用Remix调用每一个函数，提交函数调用截图
+- 第二题：增加 changePaymentAddress 函数，更改员工的薪水支付地址，思考一下能否使用modifier整合某个功能
+- 第三题（加分题）：自学C3 Linearization, 求以下 contract Z 的继承线
+- contract O
+- contract A is O
+- contract B is O
+- contract C is O
+- contract K1 is A, B
+- contract K2 is A, C
+- contract Z is K1, K2

Lesson3/assignment/yours.sol

@@ -0,0 +1,250 @@
+/*assignment 1*/
+pragma solidity ^0.4.14;
+
+/** @title Payroll contract. */
+contract Payroll {
+    struct Employee {
+        address wallet;
+        uint salary;
+        uint lastPayday;
+    }
+
+    mapping(address => Employee) public employees;
+    address owner;
+    uint totalSalary = 0;
+    uint constant payDuration = 10 seconds;
+
+    /** @dev Constructor.
+      */
+    function Payroll() {
+        owner = msg.sender;
+    }
+
+    modifier onlyOwner {
+        require(msg.sender == owner);
+        _;
+    }
+
+    modifier employeeExist(address wallet){
+        var employee = employees[wallet];
+        assert(employee.wallet != 0x0);
+        _;
+    }
+
+    /** @dev Pay employee their rest payment before any change.
+      * @param employee Employee that need to be paid.
+      */
+    function _payRestSalary(Employee employee) private {
+        uint restPayment = employee.salary * (now - employee.lastPayday) / payDuration;
+        employee.wallet.transfer(restPayment);
+    }
+
+    /** @dev Add new employee to contract.
+      * @param salary Salary of the new employee.
+      * @param wallet Wallet address of the new employee.
+      */
+    function addEmployee(uint salary, address wallet) onlyOwner {
+        var employee = employees[wallet];
+
+        employees[wallet] = Employee(wallet, salary * 1 ether, now);
+        totalSalary += employees[wallet].salary;
+    }
+
+    /** @dev Update employee in the contract.
+      * @param salary Salary of the new employee needs to be updated.
+      * @param wallet Wallet address of the employee needs to be updated.
+      */
+    function updateEmployee(uint salary, address wallet) onlyOwner employeeExist(wallet){
+        var employee = employees[wallet];
+
+        _payRestSalary(employee);
+        totalSalary = totalSalary - employees[wallet].salary;
+        employees[wallet].salary = salary * 1 ether;
+        employees[wallet].lastPayday = now;
+        totalSalary = totalSalary + employees[wallet].salary;
+    }
+
+    function checkEmployee(address wallet) returns (uint salary, uint lastPayday) {
+        var employee = employees[wallet];
+
+        salary = employee.salary;
+        lastPayday = employee.lastPayday;
+    }
+
+    /** @dev Remove employee in the contract.
+      * @param wallet Wallet address of the employee needs to be removed.
+      */
+    function removeEmployee(address wallet) onlyOwner employeeExist(wallet){
+        var employee = employees[wallet];
+
+        _payRestSalary(employee);
+        totalSalary -= employees[wallet].salary;
+        delete employees[wallet];
+    }
+
+    /** @dev add fund to employer.
+      * @return employer balance after adding fund.
+      */
+    function addFund() payable returns (uint) {
+        return this.balance;
+    }
+
+    /** @dev calculate how many times the employer can pay the employees
+      * @return the times that employees can get paid from employer's balance
+      */
+    function calculateRunway() returns (uint) {
+        return this.balance / totalSalary;
+    }
+
+    /** @dev check if employer has enough money to pay
+      * @return true means employers has enough money, false means not
+      */
+    function hasEnoughFund() returns (bool) {
+        return calculateRunway() > 0;
+    }
+
+    /** @dev pay salary to employee
+      */
+    function getPaid() employeeExist(msg.sender){
+        var employee = employees[msg.sender];
+
+        uint nextPayDay = employee.lastPayday + payDuration;
+        assert(nextPayDay < now);
+
+        employees[msg.sender].lastPayday = nextPayDay;
+        employee.wallet.transfer(employee.salary);
+    }
+}
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+/*assignment 2*/
+pragma solidity ^0.4.14;
+
+/** @title Payroll contract. */
+contract Payroll {
+    struct Employee {
+        address wallet;
+        uint salary;
+        uint lastPayday;
+    }
+
+    mapping(address => Employee) public employees;
+    address owner;
+    uint totalSalary = 0;
+    uint constant payDuration = 10 seconds;
+
+    /** @dev Constructor.
+      */
+    function Payroll() {
+        owner = msg.sender;
+    }
+
+    modifier onlyOwner {
+        require(msg.sender == owner);
+        _;
+    }
+
+    modifier employeeExist(address wallet){
+        var employee = employees[wallet];
+        assert(employee.wallet != 0x0);
+        _;
+    }
+
+    modifier employeeNotExist(address wallet){
+        assert(employees[wallet].wallet == 0x0);
+        _;
+    }
+
+    /** @dev Pay employee their rest payment before any change.
+      * @param employee Employee that need to be paid.
+      */
+    function _payRestSalary(Employee employee) private {
+        uint restPayment = employee.salary * (now - employee.lastPayday) / payDuration;
+        employee.wallet.transfer(restPayment);
+    }
+
+    /** @dev Add new employee to contract.
+      * @param salary Salary of the new employee.
+      * @param wallet Wallet address of the new employee.
+      */
+    function addEmployee(uint salary, address wallet) onlyOwner employeeNotExist(wallet){
+        var employee = employees[wallet];
+
+        employees[wallet] = Employee(wallet, salary * 1 ether, now);
+        totalSalary += employees[wallet].salary;
+    }
+
+    /** @dev Update employee in the contract.
+      * @param salary Salary of the new employee needs to be updated.
+      * @param wallet Wallet address of the employee needs to be updated.
+      */
+    function updateEmployee(uint salary, address wallet) onlyOwner employeeExist(wallet) {
+        var employee = employees[wallet];
+
+        _payRestSalary(employee);
+        totalSalary = totalSalary - employees[wallet].salary;
+        employees[wallet].salary = salary * 1 ether;
+        employees[wallet].lastPayday = now;
+        totalSalary = totalSalary + employees[wallet].salary;
+    }
+
+    function checkEmployee(address wallet) returns (uint salary, uint lastPayday) {
+        var employee = employees[wallet];
+
+        salary = employee.salary;
+        lastPayday = employee.lastPayday;
+    }
+
+    function changePaymentAddress(address oldWallet, address newWallet) onlyOwner employeeExist(oldWallet) employeeNotExist(newWallet){
+        var employee = employees[oldWallet];
+        _payRestSalary(employee);
+        var oldSalary = employee.salary;
+        removeEmployee(oldWallet);
+        addEmployee(oldSalary / 1 ether, newWallet);
+    }
+
+    /** @dev Remove employee in the contract.
+      * @param wallet Wallet address of the employee needs to be removed.
+      */
+    function removeEmployee(address wallet) onlyOwner employeeExist(wallet){
+        var employee = employees[wallet];
+
+        _payRestSalary(employee);
+        totalSalary -= employees[wallet].salary;
+        delete employees[wallet];
+    }
+
+    /** @dev add fund to employer.
+      * @return employer balance after adding fund.
+      */
+    function addFund() payable returns (uint) {
+        return this.balance;
+    }
+
+    /** @dev calculate how many times the employer can pay the employees
+      * @return the times that employees can get paid from employer's balance
+      */
+    function calculateRunway() returns (uint) {
+        return this.balance / totalSalary;
+    }
+
+    /** @dev check if employer has enough money to pay
+      * @return true means employers has enough money, false means not
+      */
+    function hasEnoughFund() returns (bool) {
+        return calculateRunway() > 0;
+    }
+
+    /** @dev pay salary to employee
+      */
+    function getPaid() employeeExist(msg.sender){
+        var employee = employees[msg.sender];
+
+        uint nextPayDay = employee.lastPayday + payDuration;
+        assert(nextPayDay < now);
+
+        employees[msg.sender].lastPayday = nextPayDay;
+        employee.wallet.transfer(employee.salary);
+    }
+}

Lesson3/orgin/README.md

@@ -0,0 +1,3 @@
+## 硅谷live以太坊智能合约 第三课
+
+这里是每一课的初始代码，有需要的同学可以参考

Lesson4/README.md

@@ -0,0 +1,16 @@
+## 硅谷live以太坊智能合约频道官方地址
+
+### 第四课《使用Truffle架构进行前后端交互，测试，部署》
+
+目录结构
+  <br/>|
+  <br/>|--orgin 课程初始代码
+  <br/>|
+  <br/>|--assignment 课程作业提交代码
+<br/> 
+### 本节知识点
+第4课：使用Truffle架构进行前后端交互，测试，部署
+- 为什么要用Truffle，Truffle的基本概念
+- Truffle 的command line 功能
+- 初始化项目与Truffle项目目录结构
+- 编译部署合约到testrpc

Lesson4/assignment/README.md

@@ -0,0 +1,12 @@
+## 硅谷live以太坊智能合约 第四课作业
+这里是同学提交作业的目录
+
+### 第四课：课后作业
+- 将第三课完成的payroll.sol程序导入truffle工程
+- 在test文件夹中，写出对如下两个函数的单元测试：
+- function addEmployee(address employeeId, uint salary) onlyOwner
+- function removeEmployee(address employeeId) onlyOwner employeeExist(employeeId)
+- 思考一下我们如何能覆盖所有的测试路径，包括函数异常的捕捉
+- (加分题,选作）
+- 写出对以下函数的基于solidity或javascript的单元测试 function getPaid() employeeExist(msg.sender)
+- Hint：思考如何对timestamp进行修改，是否需要对所测试的合约进行修改来达到测试的目的？

Lesson4/assignment/TestPayroll.js

@@ -0,0 +1,32 @@
+var Payroll = artifacts.require("./Payroll.sol");
+const ether = 1000000000000000000;
+
+contract('Payroll', function(accounts) {
+
+  it("Employee with wallet: test account[8] and salary: 1 ether should be stored.", function() {
+    return Payroll.deployed().then(function(instance) {
+      payrollInstance = instance;
+
+      return payrollInstance.addEmployee(1, accounts[8]);
+    }).then(function() {
+      return payrollInstance.isEmployeeExist.call(accounts[8]);
+    }).then(function(isExist) {
+      assert.equal(isExist, true, "The test account[9] with 1 ether salary was not stored.");
+    });
+  });
+
+  it("Employee with wallet: test account[9] and salary: 1 ether should be stored and then removed.", function() {
+    return Payroll.deployed().then(function(instance) {
+      payrollInstance = instance;
+
+      return payrollInstance.addEmployee(1, accounts[9]);
+    }).then(function() {
+      return payrollInstance.removeEmployee(accounts[9]);
+    }).then(function(){
+      return payrollInstance.isEmployeeExist.call(accounts[9]);
+    }).then(function(isExist) {
+      assert.deepEqual(isExist, false, "The test account[9] with 1 ether salary was not deleted.");
+    });
+  });
+
+});