From b0bc69c63dfe4b2d6f629d4c3726a788b65b038f Mon Sep 17 00:00:00 2001
From: Ruidy Nemausat <ruidy.nemausat@gmail.com>
Date: Tue, 14 Jul 2020 10:35:49 +0200
Subject: [PATCH] handle post request

---
 handlers/products.go             | 39 ++++++++++++++++++++++++++++++
 products/data/mockProductList.go | 25 +++++++++++++++++++
 products/data/product.go         | 41 +++++++++++++-------------------
 server/server.go                 |  4 ++--
 4 files changed, 83 insertions(+), 26 deletions(-)
 create mode 100644 products/data/mockProductList.go

diff --git a/handlers/products.go b/handlers/products.go
index e8e02b0..7b9e06f 100644
--- a/handlers/products.go
+++ b/handlers/products.go
@@ -17,7 +17,31 @@ type Products struct {
 func NewProducts(logger *log.Logger) *Products { return &Products{logger: logger} }
 
 func (p *Products) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	// get resources
+	if r.Method == http.MethodGet {
+		p.getProducts(w, r)
+		return
+	}
+	// create one resource
+	if r.Method == http.MethodPost {
+		p.addProduct(w, r)
+		return
+	}
+	// update one resource
+	// if r.Method == http.MethodPut {
+	// 	p.updateProduct(w,r)
+	// 	return
+	// }
+	// catch all other HTTP requests
+	w.WriteHeader(http.StatusMethodNotAllowed)
+}
+
+// getProducts writes all products to response in JSON format
+func (p *Products) getProducts(w http.ResponseWriter, r *http.Request) {
+	p.logger.Println("Handle 'GET' request")
+	// fetch products from the datastore
 	productList := data.AllProducts()
+	// serialize list to JSON
 	err := productList.ToJSON(w)
 	if err != nil {
 		errMsg := fmt.Sprintf("Unable to encode request: %s\n", err)
@@ -25,3 +49,18 @@ func (p *Products) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 }
+
+func (p *Products) addProduct(w http.ResponseWriter, r *http.Request) {
+	p.logger.Println("Handle 'POST' request")
+	// create a new product
+	newProd := &data.Product{}
+	// deserialize JSON to product
+	err := newProd.FromJSON(r.Body)
+	if err != nil {
+		errMsg := fmt.Sprintf("Unable to decode data: %s\n", err)
+		http.Error(w, errMsg, http.StatusBadRequest)
+		return
+	}
+	p.logger.Printf("product: %#v", newProd)
+	data.AddProduct(newProd)
+}
diff --git a/products/data/mockProductList.go b/products/data/mockProductList.go
new file mode 100644
index 0000000..87471ee
--- /dev/null
+++ b/products/data/mockProductList.go
@@ -0,0 +1,25 @@
+package data
+
+import "time"
+
+// dummy persistence layer
+var productList = []*Product{
+	{
+		ID:          1,
+		Name:        "Latte",
+		Description: "Prothy Milky Coffee",
+		Price:       2.45,
+		SKU:         "abc123",
+		CreatedOn:   time.Now().String(),
+		UpdatedOn:   time.Now().String(),
+	},
+	{
+		ID:          2,
+		Name:        "Espresso",
+		Description: "Short Strong Coffee without Milk",
+		Price:       1.99,
+		SKU:         "efg456",
+		CreatedOn:   time.Now().String(),
+		UpdatedOn:   time.Now().String(),
+	},
+}
diff --git a/products/data/product.go b/products/data/product.go
index 26bae00..76e61ac 100644
--- a/products/data/product.go
+++ b/products/data/product.go
@@ -3,7 +3,6 @@ package data
 import (
 	"encoding/json"
 	"io"
-	"time"
 )
 
 // Product defines the structure of a product
@@ -18,38 +17,32 @@ type Product struct {
 	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
 
-// All returns all existing products
+// AllProducts returns all existing products
 func AllProducts() Products {
 	return productList
 }
 
+// AddProduct add a Product to the dataStore
+func AddProduct(p *Product) {
+	p.ID = getNextID()
+	productList = append(productList, p)
+}
+
+// getNextID handle ID creation
+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
 }
-
-// dummy persistence layer
-var productList = []*Product{
-	{
-		ID:          1,
-		Name:        "Latte",
-		Description: "Prothy Milky Coffee",
-		Price:       2.45,
-		SKU:         "abc123",
-		CreatedOn:   time.Now().String(),
-		UpdatedOn:   time.Now().String(),
-	},
-	{
-		ID:          2,
-		Name:        "Espresso",
-		Description: "Short Strong Coffee without Milk",
-		Price:       1.99,
-		SKU:         "efg456",
-		CreatedOn:   time.Now().String(),
-		UpdatedOn:   time.Now().String(),
-	},
-}
diff --git a/server/server.go b/server/server.go
index eb275a2..4f88841 100644
--- a/server/server.go
+++ b/server/server.go
@@ -10,8 +10,8 @@ func New(mux *http.ServeMux, port string) *http.Server {
 	return &http.Server{
 		Addr:         port,
 		Handler:      mux,
+		ReadTimeout:  5 * time.Second,
+		WriteTimeout: 10 * time.Second,
 		IdleTimeout:  120 * time.Second, // keep connection opened to prevent Ddos attacks
-		ReadTimeout:  1 * time.Second,
-		WriteTimeout: 1 * time.Second,
 	}
 }