handle put request

README.md

@@ -0,0 +1,3 @@
+# Coffee Shop Microservice
+
+- Built with `Golang`

handlers/products.go

@@ -4,6 +4,8 @@ import (
 	"fmt"
 	"log"
 	"net/http"
+	"regexp"
+	"strconv"
 
 	"github.com/rjNemo/go-micro/products/data"
 )
@@ -28,10 +30,27 @@ func (p *Products) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	// update one resource
-	// if r.Method == http.MethodPut {
+	if r.Method == http.MethodPut {
-	// 	p.updateProduct(w,r)
+		// look for ID in the URI using regexp
-	// 	return
+		regx := regexp.MustCompile(`/([0-9]+)`)
-	// }
+		group := regx.FindAllStringSubmatch(r.URL.Path, -1)
+
+		if len(group) != 1 {
+			http.Error(w, "Invalid URI", http.StatusBadRequest)
+			return
+		}
+		if len(group[0]) != 2 {
+			http.Error(w, "Invalid URI", http.StatusBadRequest)
+			return
+		}
+
+		idString := group[0][1]
+		id, _ := strconv.Atoi(idString)
+
+		p.logger.Printf("Got ID: %d", id)
+		p.updateProduct(id, w, r)
+		return
+	}
 	// catch all other HTTP requests
 	w.WriteHeader(http.StatusMethodNotAllowed)
 }
@@ -50,6 +69,7 @@ func (p *Products) getProducts(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
+// addProduct reads request body and creates new product
 func (p *Products) addProduct(w http.ResponseWriter, r *http.Request) {
 	p.logger.Println("Handle 'POST' request")
 	// create a new product
@@ -64,3 +84,28 @@ func (p *Products) addProduct(w http.ResponseWriter, r *http.Request) {
 	p.logger.Printf("product: %#v", newProd)
 	data.AddProduct(newProd)
 }
+
+// updateProduct edit product identified by id
+func (p *Products) updateProduct(id int, w http.ResponseWriter, r *http.Request) {
+	p.logger.Println("Handle 'PUT' 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)
+	err = data.UpdateProduct(id, newProd)
+	if err == data.ErrorProductNotFound {
+		http.Error(w, err.Error(), http.StatusNotFound)
+		return
+	}
+	if err != nil {
+		errMsg := fmt.Sprintf("something went wrong: %s", err.Error())
+		http.Error(w, errMsg, http.StatusInternalServerError)
+		return
+	}
+}

products/data/product.go

@@ -2,6 +2,7 @@ package data
 
 import (
 	"encoding/json"
+	"fmt"
 	"io"
 )
 
@@ -37,6 +38,30 @@ func AddProduct(p *Product) {
 	productList = append(productList, p)
 }
 
+// UpdateProduct edits a Product identified by its id
+func UpdateProduct(id int, p *Product) error {
+	idx, _, err := findProduct(id)
+	if err != nil {
+		return err
+	}
+	p.ID = id
+	productList[idx] = p
+	return nil
+}
+
+// ErrorProductNotFound its thrown when the product is not found
+var ErrorProductNotFound = fmt.Errorf("Product not found")
+
+// findProduct retrieves a product via its unique identifier
+func findProduct(id int) (int, *Product, error) {
+	for i, p := range productList {
+		if p.ID == id {
+			return i, p, nil
+		}
+	}
+	return 0, nil, ErrorProductNotFound
+}
+
 // getNextID handle ID creation
 func getNextID() int {
 	return productList[len(productList)-1].ID + 1