GO Demo REST API

Prerequisite

GO Setup on OSX

• golang http://sourabhbajaj.com/mac-setup/Go/README.html
• dependency-management https://github.com/golang/dep

GO Setup on Windows

• golang http://www.wadewegner.com/2014/12/easy-go-programming-setup-for-windows/
• dependency-management https://golang.github.io/dep/docs/installation.html

Install Dependencies

$ dep status
$ dep ensure

Setup Environment

This application needs following env variables to use the auth0 authentication.

Environment	Value	Example
AUTH0_AUDIENCE	api identity	custom_identity
AUTH0_ISSUER	issuer url	https://xy.eu.auth0.com/
AUTH0_JWKS	keystore json	https://../.well-known/jwks.json

Run

$ docker-compose up 
$ go build && ./go-basics

• http://localhost:8000/users
• http://localhost:8000/groups
• http://localhost:8000/transactions protected

Build & Deploy

Heroku Cloud

Deploy to heroku cloud https://biergit.herokuapp.com

$ make
$ make build
$ cf push -f manifest.yml

Pivotal Cloud

Deploy to pivotal cloud https://biergit-api.cfapps.io

$ make
$ make deploy

Layout

  +--------------------------------------------------+   +-----------------+
  |                      api                         |   |     vendor      |
  |--------------------------------------------------|   |-----------------|
  | +---------+  +---------+  +---------+  +-------+ |   |                 |
  | |         |  |         |  |         |  |       | |   |                 |
  | |         |  |         |  |         |  |       | |   |                 |
  | |         |  |         |  |         |  |       | |   |                 |
  | |         |  |         |  |         |  |       | |   |                 |
  | | handler |+>| service |+>|  repo   |+>|  db   | |   |  vendor pkgs    |
  | |         |  |         |  |         |  |       | |   |                 |
  | |         |  |         |  |         |  |       | |   |                 |
  | |         |  |         |  |         |  |       | |   |                 |
  | |         |  |         |  |         |  |       | |   |                 |
  | +---------+  +---------+  +---------+  +-------+ |   |                 |
  +--------------------------------------------------+   +-----------------+

Logging

Use this logging mechanism to be indexed by a logging system https://github.com/sirupsen/logrus

import (
	log "github.com/sirupsen/logrus"
)

log.WithFields(log.Fields{
		"key": "value",
	}).Debug("Save user in repository")
	
Result: time="2019-04-08T23:31:03+02:00" level=debug msg="Save user in repository" user_id=0

Swagger

dep ensure -add github.com/go-swagger/go-swagger/cmd/swagger

Use this commenting style to be scanned by swagger generator

// swagger:operation GET /repo/{author} repos repoList
// ---
// summary: List the repositories owned by the given author.
// description: If author length is between 6 and 8, Error Not Found (404) will be returned.
// parameters:
// - name: author
//   in: path
//   description: username of author
//   type: string
//   required: true
// responses:
//   "200":
//     "$ref": "#/responses/reposResp"
//   "404":
//     "$ref": "#/responses/notFound"

Use this commenting style for model

// Description of the Model
// swagger:model User

Use this commenting style for main package

// API REST EXAMPLE
//
// This is a example over how to create the api from the source.
//
//     Schemes: http, https
//     Host: localhost:3000
//     Version: 0.1.0
//     basePath: /api
//
//     Consumes:
//     - application/json
//
//     Produces:
//     - application/json
//
// swagger:meta
package main

Use these commands to generate swagger spec file and serve it

cd cmd/biergit
swagger generate spec -o ../../swagger.json
swagger serve -p 8008 -F redoc ../../swagger.json

Generate GO Docs

run godoc -http=:6060 -v

http://localhost:6060/pkg/git.skydevelopment.ch/zrh-dev/go-basics/

Sources

Basics

• https://github.com/Alikhll/golang-developer-roadmap
• https://awesome-go.com/
• https://hackernoon.com/basics-of-golang-for-beginners-6bd9b40d79ae

Conventions

• http://goinbigdata.com/golang-pass-by-pointer-vs-pass-by-value/
• https://golang.org/doc/effective_go.html

Layout & Architecture

• https://www.youtube.com/watch?v=cmkKxNN7cs4
• https://www.youtube.com/watch?v=1rxDzs0zgcE
• https://blog.cleancoder.com/uncle-bob/2012/08/13/the-clean-architecture.html
• https://github.com/golang-standards/project-layout
• https://hackernoon.com/golang-clean-archithecture-efd6d7c43047
• https://rakyll.org/style-packages/
• https://www.reddit.com/r/golang/comments/8g26il/what_is_the_recommended_go_project_folder/

Interfaces

• https://blog.chewxy.com/2018/03/18/golang-interfaces/

Persistence

• https://www.reddit.com/r/golang/comments/8j3219/anyone_using_gorm_in_production_is_it_slow/
• http://doc.gorm.io
• https://godoc.org/github.com/knq/dburl
• https://www.alexedwards.net/blog/organising-database-access

Networking

• https://echo.labstack.com/guide
• http://www.gorillatoolkit.org/pkg/mux
• https://www.codementor.io/codehakase/building-a-restful-api-with-golang-a6yivzqdo

Json

• https://golang.org/pkg/encoding/json

Error Handling

• https://blog.golang.org/error-handling-and-go

Configuration

• http://goinbigdata.com/persisting-application-configuration-in-golang/

Cloud Foundry

• https://github.com/cloudfoundry-community/go-cfenv

Docs

• https://blog.golang.org/godoc-documenting-go-code

Best Practices

• https://peter.bourgon.org/go-in-production/