feat(server): 初始化HTTP服务器并添加产品数据结构

- 创建基础HTTP服务器，监听localhost:5000
- 实现StringHandle结构体处理HTTP请求
- 添加请求日志打印功能
- 忽略/favicon.ico请求并返回404状态
- 定义Product结构体及示例数据
- 实现产品税费计算和折扣应用方法

24-httpserver/httpserver/go.mod

@@ -0,0 +1,3 @@
+module httpserver
+
+go 1.22

24-httpserver/httpserver/main.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"io"
+	"net/http"
+)
+
+type StringHandle struct {
+	message string
+}
+
+func (sh *StringHandle) ServeHTTP(writer http.ResponseWriter, request *http.Request) {
+
+	Printfln("\n----------\nMethod: %v Protocol: %v Host: %v URL: %v URL.Host: %v RequestURI: %v",
+		request.Method, request.Proto, request.Host,
+		request.URL.String(), request.URL.Host, request.RequestURI)
+	for name, val := range request.Header {
+		Printfln("Header: %v = %v", name, val)
+	}
+	Printfln("RemoteAddr: %v", request.RemoteAddr)
+	Printfln("ContentLength: %v", request.ContentLength)
+	Printfln("Body: %v", request.Body)
+	Printfln("TLS: %v", request.TLS)
+	Printfln("--------------")
+	if request.URL.Path == "/favicon.ico" {
+		Printfln("Request for favicon.ico detected - returning 404")
+		Printfln("--------------\n")
+		writer.WriteHeader(http.StatusNotFound)
+		return
+	}
+	writeLen, err := io.WriteString(writer, sh.message)
+	if err != nil {
+		Printfln("ServeHTTP Error: %v", err)
+		return
+	}
+	Printfln("ServeHTTP Wrote %d bytes", writeLen)
+	Printfln("--------------\n")
+}
+
+func main() {
+	err := http.ListenAndServe("localhost:5000", &StringHandle{message: "Hello World!"})
+	if err != nil {
+		Printfln("ListenAndServe Error: %v", err)
+		return
+	}
+}

24-httpserver/httpserver/printer.go

@@ -0,0 +1,7 @@
+package main
+
+import "fmt"
+
+func Printfln(template string, values ...interface{}) {
+	fmt.Printf(template+"\n", values...)
+}

24-httpserver/httpserver/product.go

@@ -0,0 +1,31 @@
+package main
+
+type Product struct {
+	Name, Category string
+	Price          float64
+}
+
+var Kayak = Product{
+	Name:     "Kayak",
+	Category: "Watersports",
+	Price:    279,
+}
+
+var ProductList = []Product{
+	{"Kayak", "Watersports", 279},
+	{"LifeJacket", "Watersports", 49.95},
+	{"Soccer Ball", "Soccer", 19.50},
+	{"Corner Flags", "Soccer", 34.95},
+	{"Stadium", "Soccer", 79500},
+	{"Thinking Cap", "Chess", 16},
+	{"Unsteady Chair", "Chess", 75},
+	{"Bling-Bling King", "Chess", 1200},
+}
+
+func (p *Product) AddTax() float64 {
+	return p.Price * 1.2
+}
+
+func (p *Product) ApplyDiscount(amount float64) float64 {
+	return p.Price - amount
+}