🧹 clean code structure

main.go

@@ -3,54 +3,49 @@ package main
 import (
 	"context"
 	"log"
-	"net/http"
 	"os"
 	"os/signal"
 	"time"
 
 	"github.com/gorilla/mux"
-	"github.com/rjNemo/go-micro/handlers"
+
+	"github.com/rjNemo/go-micro/products/handlers"
 	"github.com/rjNemo/go-micro/server"
 )
 
 const port = ":5000"
 
 func main() {
+	// create a logger to control application wide logging
 	logger := log.New(os.Stdout, "Product API: ", log.LstdFlags|log.Lshortfile)
 
-	// create the handlers
-	productsHandler := handlers.NewProducts(logger)
-	// create a server mux and register the handlers
+	// create a router
 	router := mux.NewRouter()
-	// GET
-	getRouter := router.Methods(http.MethodGet).Subrouter()
-	getRouter.HandleFunc("/", productsHandler.GetProducts)
-	// POST
-	postRouter := router.Methods(http.MethodPost).Subrouter()
-	postRouter.HandleFunc("/", productsHandler.AddProduct)
-	postRouter.Use(productsHandler.ProductValidationMiddleware)
-	// PUT
-	putRouter := router.Methods(http.MethodPut).Subrouter()
-	putRouter.HandleFunc("/{id:[0-9]+}", productsHandler.UpdateProduct)
-	putRouter.Use(productsHandler.ProductValidationMiddleware)
 
-	// creates a new server
+	// create the handler
+	productsHandler := handlers.New(logger)
+
+	// register the handler method to the router
+	productsHandler.RegisterRoutes(router)
+
+	// creates a production-ready server using the handler
 	srv := server.New(router, port)
 
-	// non blocking application server
+	// start a non blocking application server
 	go func() {
-		logger.Printf("Server started at address http://localhost%s...", port)
-		logger.Fatalf("Server failed: %v", srv.ListenAndServe())
+		logger.Printf("Server started at address http://localhost%s ...", port)
+		logger.Fatalf("Server failed: %v", srv.ListenAndServe()) // TODO: use ListenAndServeTLS in production
 	}()
 
 	// catch sigterm or interrupt and gracefully terminates the server
 	sigChan := make(chan os.Signal)
-	signal.Notify(sigChan, os.Interrupt)
-	signal.Notify(sigChan, os.Kill)
-
+	signal.Notify(sigChan, os.Interrupt) // interrupt
+	signal.Notify(sigChan, os.Kill)      // sigterm
+	// log received signal
 	sig := <-sigChan
 	logger.Printf("Received %v signal... graceful shutdown", sig)
 
-	toCtx, _ := context.WithTimeout(context.Background(), 30*time.Second)
+	toCtx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	cancel()
 	srv.Shutdown(toCtx)
 }

products/data/mockProductList.go

@@ -1,9 +1,13 @@
 package data
 
-import "time"
+import (
+	"time"
+
+	"github.com/rjNemo/go-micro/products/models"
+)
 
 // dummy persistence layer
-var productList = []*Product{
+var productList = []*models.Product{
 	{
 		ID:          1,
 		Name:        "Latte",

products/data/product.go

@@ -4,28 +4,18 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+
+	"github.com/rjNemo/go-micro/products/models"
 )
 
-// Product defines the structure of a product
-type Product struct {
-	ID          int     `json:"id"` //TODO: use uuid
-	Name        string  `json:"name"`
-	Description string  `json:"description"`
-	Price       float32 `json:"price"` // TODO: use int
-	SKU         string  `json:"sku"`
-	CreatedOn   string  `json:"-"`
-	UpdatedOn   string  `json:"-"`
-	DeletedOn   string  `json:"-"`
-}
-
-// FromJSON read JSON data to create a new product
-func (p *Product) FromJSON(r io.Reader) error {
-	return json.NewDecoder(r).Decode(p)
-}
-
 // Products is the collection of products.
 // It encapsulates data access logic
-type Products []*Product
+type Products []*models.Product
+
+// ToJSON returns all existing product in JSON format
+func (p *Products) ToJSON(w io.Writer) error {
+	return json.NewEncoder(w).Encode(p) // more efficient in memory and time than Marshal
+}
 
 // AllProducts returns all existing products
 func AllProducts() Products {
@@ -33,13 +23,13 @@ func AllProducts() Products {
 }
 
 // AddProduct add a Product to the dataStore
-func AddProduct(p *Product) {
+func AddProduct(p *models.Product) {
 	p.ID = getNextID()
 	productList = append(productList, p)
 }
 
 // UpdateProduct edits a Product identified by its id
-func UpdateProduct(id int, p *Product) error {
+func UpdateProduct(id int, p *models.Product) error {
 	idx, _, err := findProduct(id)
 	if err != nil {
 		return err
@@ -53,7 +43,7 @@ func UpdateProduct(id int, p *Product) error {
 var ErrorProductNotFound = fmt.Errorf("Product not found")
 
 // findProduct retrieves a product via its unique identifier
-func findProduct(id int) (int, *Product, error) {
+func findProduct(id int) (int, *models.Product, error) {
 	for i, p := range productList {
 		if p.ID == id {
 			return i, p, nil
@@ -66,8 +56,3 @@ func findProduct(id int) (int, *Product, error) {
 func getNextID() int {
 	return productList[len(productList)-1].ID + 1
 }
-
-// ToJSON returns all existing product in JSON format
-func (p *Products) ToJSON(w io.Writer) error {
-	return json.NewEncoder(w).Encode(p) // more efficient in memory and time than Marshal
-}

products/handlers/products.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/gorilla/mux"
 	"github.com/rjNemo/go-micro/products/data"
+	"github.com/rjNemo/go-micro/products/models"
 )
 
 // Products is a handler for Products API service
@@ -16,8 +17,10 @@ type Products struct {
 	logger *log.Logger
 }
 
-// NewProducts creates a Products handler
-func NewProducts(logger *log.Logger) *Products { return &Products{logger: logger} }
+// New creates a Products handler
+func New(logger *log.Logger) *Products {
+	return &Products{logger: logger}
+}
 
 // GetProducts writes all products to response in JSON format
 func (p *Products) GetProducts(w http.ResponseWriter, r *http.Request) {
@@ -37,7 +40,7 @@ func (p *Products) GetProducts(w http.ResponseWriter, r *http.Request) {
 func (p *Products) AddProduct(w http.ResponseWriter, r *http.Request) {
 	p.logger.Println("Handle 'POST' request")
 	// get product from the request
-	newProd := r.Context().Value(KeyProduct{}).(*data.Product) // cast into a Product
+	newProd := r.Context().Value(KeyProduct{}).(*models.Product) // cast into a Product
 
 	p.logger.Printf("product: %#v", newProd)
 	data.AddProduct(newProd)
@@ -50,7 +53,7 @@ func (p *Products) UpdateProduct(w http.ResponseWriter, r *http.Request) {
 
 	p.logger.Println("Handle 'PUT' request", id)
 	// get product from the request
-	newProd := r.Context().Value(KeyProduct{}).(*data.Product) // cast into a Product
+	newProd := r.Context().Value(KeyProduct{}).(*models.Product) // cast into a Product
 
 	p.logger.Printf("product: %#v", newProd)
 	err := data.UpdateProduct(id, newProd)
@@ -72,7 +75,7 @@ type KeyProduct struct{}
 func (p *Products) ProductValidationMiddleware(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		// create a new product
-		newProd := &data.Product{}
+		newProd := &models.Product{}
 		// deserialize JSON to product
 		err := newProd.FromJSON(r.Body)
 		if err != nil {
@@ -88,3 +91,18 @@ func (p *Products) ProductValidationMiddleware(next http.Handler) http.Handler {
 		next.ServeHTTP(w, req)
 	})
 }
+
+// RegisterRoutes associates path to controller
+func (p *Products) RegisterRoutes(r *mux.Router) {
+	// GET
+	getRouter := r.Methods(http.MethodGet).Subrouter()
+	getRouter.HandleFunc("/", p.GetProducts)
+	// POST
+	postRouter := r.Methods(http.MethodPost).Subrouter()
+	postRouter.HandleFunc("/", p.AddProduct)
+	postRouter.Use(p.ProductValidationMiddleware)
+	// PUT
+	putRouter := r.Methods(http.MethodPut).Subrouter()
+	putRouter.HandleFunc("/{id:[0-9]+}", p.UpdateProduct)
+	putRouter.Use(p.ProductValidationMiddleware)
+}

products/models/product.go

@@ -0,0 +1,23 @@
+package models
+
+import (
+	"encoding/json"
+	"io"
+)
+
+// Product defines the structure of a product
+type Product struct {
+	ID          int     `json:"id"` //TODO: use uuid
+	Name        string  `json:"name"`
+	Description string  `json:"description"`
+	Price       float32 `json:"price"` // TODO: use int
+	SKU         string  `json:"sku"`
+	CreatedOn   string  `json:"-"`
+	UpdatedOn   string  `json:"-"`
+	DeletedOn   string  `json:"-"`
+}
+
+// FromJSON read JSON data to create a new product
+func (p *Product) FromJSON(r io.Reader) error {
+	return json.NewDecoder(r).Decode(p)
+}