RestApiExampleAndCompiler.go

/**

Instalar libreria mux para perticiones http
$> go get github.com/gorilla/mux

Para ejecutar como script
$> go run demo-api.go

Para compilar Windows:
$> go build -o demo-api.exe demo-api.go
$> demo-api.exe

Para compilar Linux
$> go build -o demo-api demo-api.go
$> ./demo-api

https://www.ardanlabs.com/blog/2013/10/cross-compile-your-go-programs.html
https://www.digitalocean.com/community/tutorials/how-to-build-go-executables-for-multiple-platforms-on-ubuntu-16-04
https://medium.com/@utranand/building-golang-package-for-linux-from-windows-22fa23764808
https://itnext.io/building-a-web-http-server-with-go-6554029b4079
https://www.phpflow.com/golang/http-request-example-using-golang-mux/
https://medium.com/@hugo.bjarred/rest-api-with-golang-and-mux-e934f581b8b5
https://forum.golangbridge.org/t/how-to-run-a-golang-program-on-https/8136

$GOOS     $GOARCH
darwin    386      – 32 bit MacOSX
darwin    amd64    – 64 bit MacOSX
freebsd   386
freebsd   amd64
linux     386      – 32 bit Linux
linux     amd64    – 64 bit Linux
linux     arm      – RISC Linux
netbsd    386
netbsd    amd64
openbsd   386
openbsd   amd64
plan9     386
windows   386      – 32 bit Windows
windows   amd64    – 64 bit Windows

$> go run demo-api.go
$> go env

Windows POWERSHELL
$> $env:GOOS = "windows"; $env:GOARCH = "amd64"; go build -o demo-api-windows.exe demo-api.go;
$> $env:GOOS = "linux"; $env:GOARCH = "arm"; go build -o demo-api-linux demo-api.go;


Linux Consola
$> export GOOS="windows" && export GOARCH="amd64" &&  go build -o demo-api-windows.exe demo-api.go
$> export GOOS="linux" && export GOARCH="arm" &&  go build -o demo-api-linux demo-api.go;

GOOS=darwin GOARCH=386 go build test.go

Permisos de ejecucion en linux
$> chmod +x demo-api-linux
$> ./demo-api-linux

https://www.ianlewis.org/en/http2-and-go
https://www.kaihag.com/https-and-go/
https://github.com/denji/golang-tls
http.ListenAndServeTLS()

**/

package main

import (
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"time"

	"github.com/gorilla/mux"
)

// Person : Almacena informaciond de una persona
type Person struct {
	ID        string   `json:"id,omitempty"`
	FirstName string   `json:"firstname,omitempty"`
	LastName  string   `json:"lastname,omitempty"`
	Address   *Address `json:"address,omitempty"`
}

// Address :
type Address struct {
	City  string `json:"city,omitempty"`
	State string `json:"state,omitempty"`
}

// Saludo :
type Saludo struct {
	Message  string //`Message:"message,omitempty"`
	Datetime string //`Datetime:"datetime,omitempty"`
}

var people []Person

// ========= EndPoints ===============

// GetHelloEndpoint :
func GetHelloEndpoint(w http.ResponseWriter, req *http.Request) {
	json.NewEncoder(w).Encode(Saludo{Message: "Hello", Datetime: time.Now().String()})
}

// GetPersonEndpoint :
func GetPersonEndpoint(w http.ResponseWriter, req *http.Request) {
	params := mux.Vars(req)
	for _, item := range people {
		if item.ID == params["id"] {
			json.NewEncoder(w).Encode(item)
			return
		}
	}
	json.NewEncoder(w).Encode(&Person{})
}

// GetPeopleEndpoint :
func GetPeopleEndpoint(w http.ResponseWriter, req *http.Request) {
	json.NewEncoder(w).Encode(people)
}

// CreatePersonEndpoint :
func CreatePersonEndpoint(w http.ResponseWriter, req *http.Request) {
	params := mux.Vars(req)
	var person Person
	_ = json.NewDecoder(req.Body).Decode(&person)
	person.ID = params["id"]
	people = append(people, person)
	json.NewEncoder(w).Encode(people)

}

// DeletePersonEndpoint :
func DeletePersonEndpoint(w http.ResponseWriter, req *http.Request) {
	params := mux.Vars(req)
	for index, item := range people {
		if item.ID == params["id"] {
			people = append(people[:index], people[index+1:]...)
			break
		}
	}
	json.NewEncoder(w).Encode(people)
}

func main() {
	port := 3002
	router := mux.NewRouter()

	// adding example data
	people = append(people, Person{ID: "1", FirstName: "Ryan", LastName: "Ray", Address: &Address{City: "Dubling", State: "California"}})
	people = append(people, Person{ID: "2", FirstName: "Maria", LastName: "Ray"})

	// endpoints
	router.HandleFunc("/", GetHelloEndpoint).Methods("GET")
	router.HandleFunc("/people", GetPeopleEndpoint).Methods("GET")
	router.HandleFunc("/people/{id}", GetPersonEndpoint).Methods("GET")
	router.HandleFunc("/people/{id}", CreatePersonEndpoint).Methods("POST")
	router.HandleFunc("/people/{id}", DeletePersonEndpoint).Methods("DELETE")

	portString := fmt.Sprintf("%s%d", ":", port)

	fmt.Println(time.Now().String(), " --> Listen port->", portString)
	log.Fatal(http.ListenAndServe(portString, router))
}