Refactor server: use render func for templates

server/errors.go

@@ -0,0 +1,13 @@
+package server
+
+import (
+	"fmt"
+	"net/http"
+)
+
+func errorPage(err error, status int) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(status)
+		fmt.Fprint(w, err.Error())
+	}
+}

server/fetcher.go

@@ -0,0 +1,5 @@
+package server
+
+import "net/http"
+
+type fetcher func(r *http.Request) (any, error)

server/get.go

@@ -1,57 +1,44 @@
 package server
 
 import (
-	"fmt"
 	"net/http"
 	"strconv"
 	"strings"
-	"time"
 
 	"github.com/Bronku/iroon/store"
 )
 
-func (h *Server) index(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("content-type", "text/html")
-	orders, err := h.s.GetOrders()
-	if err != nil {
-		fmt.Fprint(w, "server side error getting orders: ", err)
-		return
-	}
-	err = h.tmpl.ExecuteTemplate(w, "index.html", orders)
-	if err != nil {
-		fmt.Println("error executing the template: ", err)
-	}
+func (h *Server) index(r *http.Request) (any, error) {
+	return h.s.GetOrders()
 }
 
-func (h *Server) getOrder(w http.ResponseWriter, r *http.Request) {
-	url := strings.Split(r.URL.String(), "/")
-	o := store.Order{
-		ID:   -1,
-		Date: time.Now(),
-	}
-	id, err := strconv.Atoi(url[2])
-	if err == nil {
-		newOrder, err := h.s.GetOrder(id)
-		if err == nil {
-			o = newOrder
-		}
-	}
+func (h *Server) order(r *http.Request) (any, error) {
 	type formData struct {
 		Order     store.Order
 		Catalogue []store.Cake
 	}
+	var err error
+	var data formData
 
-	cakes, err := h.s.GetCakes()
+	data.Catalogue, err = h.s.GetCakes()
 	if err != nil {
-		fmt.Fprint(w, "server side error getting available cakes: ", err)
-		return
+		return nil, err
 	}
-	data := formData{o, cakes}
-	//fmt.Println(data)
 
-	w.Header().Set("content-type", "text/html")
-	err = h.tmpl.ExecuteTemplate(w, "order.html", data)
-	if err != nil {
-		fmt.Println("error executing the template: ", err)
+	url := strings.Split(r.URL.String(), "/")
+	if len(url) < 3 || url[2] == "" {
+		return data, nil
 	}
+
+	id, err := strconv.Atoi(url[2])
+	if err != nil {
+		return nil, err
+	}
+
+	data.Order, err = h.s.GetOrder(id)
+	if err != nil {
+		return nil, err
+	}
+
+	return data, nil
 }

server/server.go

@@ -31,8 +31,8 @@ func (h *Server) openStore() error {
 func (h *Server) loadHandler() {
 	mux := http.NewServeMux()
 
-	mux.HandleFunc("GET /order/", h.getOrder)
-	mux.HandleFunc("GET /", h.index)
+	mux.HandleFunc("GET /order/", h.render(h.order, "order.html"))
+	mux.HandleFunc("GET /", h.render(h.index, "index.html"))
 	mux.HandleFunc("POST /order/", h.postOrder)
 
 	h.Handler = mux

server/template.go

@@ -3,6 +3,7 @@ package server
 import (
 	"embed"
 	"html/template"
+	"net/http"
 )
 
 //go:embed templates/*
@@ -13,3 +14,18 @@ func (h *Server) loadTemplates() error {
 	h.tmpl, err = template.ParseFS(templates, "templates/*")
 	return err
 }
+
+func (s *Server) render(fetch fetcher, templateName string) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("content-type", "text/html")
+		data, err := fetch(r)
+		if err != nil {
+			errorPage(err, http.StatusInternalServerError).ServeHTTP(w, r)
+			return
+		}
+		err = s.tmpl.ExecuteTemplate(w, templateName, data)
+		if err != nil {
+			errorPage(err, http.StatusInternalServerError).ServeHTTP(w, r)
+		}
+	}
+}

store/store.go

@@ -76,7 +76,7 @@ func (s *Store) GetCakes() ([]Cake, error) {
 
 func (s *Store) SaveCake(newCake Cake) (int, error) {
 	query := "insert into cake(name, price) values (?, ?) returning id;"
-	if newCake.ID != -1 {
+	if newCake.ID != 0 {
 		query = "update cake set name = ? , price = ? where id = "
 		query += strconv.Itoa(newCake.ID) + " returning id;"
 	}
@@ -181,7 +181,7 @@ func (s *Store) GetOrders() ([]Order, error) {
 
 func (s *Store) SaveOrder(newOrder Order) (int, error) {
 	query := "insert into customer_order(name, surname, phone, location, order_date, delivery_date, status, paid) values (?, ?, ?, ?, ?, ?, ?, ?) returning id;"
-	if newOrder.ID != -1 {
+	if newOrder.ID != 0 {
 		query = "update customer_order set name = ?, surname = ?, phone = ?, location = ?, order_date = ?, delivery_date = ?, status = ?, paid = ? where id = "
 		query += strconv.Itoa(newOrder.ID) + " returning id;"
 	}