All Design Patterns in Go (Golang)
什么是设计模式？ 在给定条件下，解决问题一种通用，可重用的方案；
In software engineering, a software design pattern is a general, reusable solution to a commonly occurring problem within a given context in software design.
设计模式分类 门面模式,外观模式（facade pattern） 1. definition 隐藏内部复杂的实现细节;对外只暴露简单的接口
2.problem Statement 客户端使用一个复杂系统的时候，必须得了解它底层的实现细节。 (In order to use the complex system, the client had to know the underlying details.)
USB stands for Universal Serial Bus
常用命令 go get 下载对应的包和它的依赖，并调用go install安装 Get downloads the packages named by the import paths, along with their dependencies. It then installs the named packages, like ‘go install ‘.
download way https: git clone https://s ssh: 1 2 [url "ssh://git@github.com/"] insteadOf = https://github.com/ git clone ssh://git@github.com/ -u: 升级包和它的依赖(默认 get只会检查是否已经缺失的包，不会去安装它)
-d:
源码 1 2 3 4 5 6 7 // Phase 1. Download/update. for _, pkg := range downloadPaths(args) { download(pkg, nil, &stk, mode) } // Phase3.
类型分类 1. 值类型和指针类型 值类型: 变量之间传递的的是值的拷贝 指针类型: 变量之间传递的是指针的拷贝 1. 基础类型 1 2 3 4 int float32, float64 bool string 2.复合类型 container
arrary slice map struct
pointer
channel
function
interface
3. 类型的声明（type declaration） 1. type definitions vs type alias 1 2 3 4 5 6 7 8 9 10 // 1. basic type type A int // 2. struct type Bird struct { } // 3. interface type BirdInterface interface { } 2.
Interfaces Explained
1. what is is a type contain a set of method signature 2. used for 引入一个中间层，调用方和实现方解耦 3.type assertion vs type conversions assertion: 将interface 抓换为 具体类型 1 2 var a interface{} = 100; var aa,ok = a.(string) conversions 4. compile time check 5. interface with pointer and value if methods receiver is value; then value and pointer implement the interface for pointer, it could get value by dereference; then copy it;
Test Driven Development: what it is, and what it is not.
basic concept unit test; integration test unit: small piece of code integration test a gropu of unit TTD test driven development
write test implement the code Refactor test first development:
先写单元测试，再实现具体逻辑，再重构 以单元测试作为驱动；
test sql sql mock real test testMain 1 2 3 4 5 6 7 func TestMain(m *testing.M) { log.Println("Do stuff BEFORE the tests!") exitVal := m.Run() log.Println("Do stuff AFTER the tests!
