Golang and basic Docker

This slide is made to share knowledge for Orcsoft company's employees. This session shared basic knowledge of Go programming (Golang) and how to implement by using various technology(ies) and framework the company use in a project for a customer.

#golang

Transcript

1. Go programming and Basic Docker Orcsoft Co., Ltd. - internal training Natth Wetchapan Senior Software Engineer
2. Syllabus - Why Go? - Needed tools for development - Basic Golang - Create a web service API - Go Module - Basic Docker
3. Why Go? - History “Go is a programming language designed by Google to help solve Google's problems, and Google has big problems.” - https://talks.golang.org/2012/splash.article go.org has already been used -> golang.org -> folks call it Golang
4. Why Go? - History(con.) - Big (large scale of) hardware - Big (large scale of) software - Big variation of programming language (mostly in C++ and a lot in Java, and Python) - Big team of engineers
5. Why Go? - in short "Go is a compiled, concurrent, garbage-collected, statically typed language developed at Google." - https://talks.golang.org/2012/splash.article
6. Why Go? - History(con.) Ken Thompson B language, C language, UTF-8 credit information from: wikipedia.org credit image from: https://www.youtube.com/watch?v=sln-gJaURzk Rob Pike Unix, UTF-8 Robert Griesemer JVM Hotspot
7. Why Go? - Who use Golang?
8. Needed tools for development 1. Install using brew $ brew install golang 2. Install by execution file https://golang.org/doc/install Setting environment ( Unix ) ( DOS ) export GOPATH=$HOME/go set GOPATH=c:\Users\%USERNAME%\go export PATH=$PATH:$GOPATH/bin set PATH=%PATH%;%GOPATH%\bin
9. Needed tools for development(con.) Text Editor Code Editor Integrated Development Environment (IDE) GoLand by Intellij Goclipse by Eclipse Notepad Vim Visual Studio Code Sublime Text
10. Basic Golang(con.) Testing Hello, World!
11. Package Basic Golang - primeRK int + ToLower(s string) string + ToUpper(s string) string - hasStr(sep string) (uint32, uint32) ... strings - signingMethods map[string]func() + Token string + RegisterSigningMethod(alg string, f func() SigningMethod) + GetSigningMethod(alg string) (method SigningMethod) ... jwt “+” Public method/variable “-” Private method/variable
12. Basic Golang(con.) Variable Declaration - Full declaration - Short declaration - Constants - Make! Default value
13. Basic Golang(con.) Function Declaration - Global variable declaration - Struct declaration - Function declaration - Interface declaration
14. Basic Golang(con.) Import Declaration - Single declaration - Multiple declaration
15. Basic Golang(con.) IF - ELSE statement - && (logical and operation) - || (logical or operation) - == (equal operation) - != (not equal operation)
16. Basic Golang(con.) Switch case - No need to BREAK
17. Basic Golang(con.) Loop - common loop - range - forever (DON’T)
18. Basic Golang(con.) Array [N]Type [N]Type{value1, value2, ..., valueN} [...]Type{value1, value2, ..., valueN} Slice make([]Type, length, capacity) make([]Type, length) []Type{} []Type{value1, value2, ..., valueN}
19. Basic Golang(con.) Function - function name - parameter - return type - function body
20. Basic Golang(con.) Strings Library - strings.Join - strings.ToUpper / ToLower - strings.Compare - strings.Contains ... - etc.
21. Basic Golang(con.) Pointer * - Asterisk: declare pointer, get value of addr & - Ampersand: get address
22. Basic Golang(con.) map
23. Basic Golang(con.) struct ... or
24. Basic Golang(con.) struct + function + pointer
25. Basic Golang(con.) Interface - flexible - scalable - polymorphism
26. Basic Golang(con.) More to read... - Goroutine - Channel
27. Create a web service API Installation $ go get -u github.com/labstack/echo/...
28. Create a web service API(con.) Hello, World! $ go get -u github.com/labstack/echo/… $ mkdir hello; cd hello $ touch main.go
29. Create a web service API(con.) Middleware - echo.Pre() middleware which is executed before router processes the request - echo.Use() middleware which is executed after router processes the request, this middleware has full access to echo.Context API Learn more: https://echo.labstack.com/middleware
30. Create a web service API(con.) Routing - GET Handle GET request method - POST Handle POST request method - Group Group a specific path of route
31. Create a web service API(con.) Authentication
32. Create a web service API(con.) Binding
33. Go Modules - Dependency - Version control - Develop anywhere For more information: https://github.com/golang/go/wiki/Modules ps. Go Module directory should be outside of $GOPATH Goodbye $GOPATH. Hello, Go Modules.
34. Go Modules(con.) - $ go mod init - GO111MODULE=on go mod init (for older version) - $ go mod tidy - add missing and remove unused modules - $ go mod vendor - make vendored copy of dependencies - $ go mod download - download modules to local cache, can use $go clean to delete
35. Basic Docker Benefits - Isolation - Lightweight - Simplicity - Workflow - Community
36. Basic Docker(con.) Docker Platform = Docker Engine + Docker Hub - Docker Engine - Docker Daemon - Docker CLI - Docker Hub
37. Basic Docker(con.) Docker Daemon - Builds Images - Runs and Manages Containers - RESTful API
38. Basic Docker(con.) Docker CLI - docker build # Build an image from a Dockerfile - docker images # List all images on a Docker host - docker run # Run an image - docker ps # List all running and stopped instances - docker stop # Stop a running instances - docker rm # Remove an instance - docker rmi # Remove an image
39. Basic Docker(con.) File Structure httpserver - main.go - Dockerfile - go.mod - go.sum $ docker build -t httpserver . $ docker images
40. Basic Docker(con.) Multi-state build - Reduce image size - Remove unnecessary files $ docker build -t httpserver_prod . $ docker run httpserver --name goservice -p 8080:80
41. Time to connect them all together! (LAB time)