diff --git a/cmd b/cmd
deleted file mode 100644
index 8b13789..0000000
--- a/cmd
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/cmd/run.go b/cmd/run.go
new file mode 100644
index 0000000..030f8c8
--- /dev/null
+++ b/cmd/run.go
@@ -0,0 +1,119 @@
+package cmd
+
+import (
+	"crypto/tls"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"log"
+	"net"
+	"net/http"
+	"time"
+)
+
+// init 函数，初始化参数
+func init() {
+	// 传递参数 -l 指定域名
+	flag.StringVar(&Domain, "l", "", "Please enter a valid HTTPS link, multiple domains are separated by commas")
+	// 支持传递参数 -t 指定超时时间,单位为秒
+	flag.IntVar(&TimeOut, "t", 5, "Please enter a valid timeout, the unit is seconds, the default is 5 seconds")
+	// 支持传递参数 -w 指定是否开启 HTTP 服务
+	flag.BoolVar(&Weh, "w", false, "This parameter is used to enable web，default is false，default port is 8080")
+	// 支持传递参数 -a 指定 HTTP 服务的地址
+	flag.StringVar(&Address, "a", "0.0.0.0", "This parameter is used to specify the address of the HTTP service")
+	// 支持传递参数 -p 指定 HTTP 服务的端口
+	flag.StringVar(&Port, "p", "8080", "This parameter is used to specify the port of the HTTP service")
+	// 解析传递的参数到 Domain 这个变量
+	flag.Parse()
+}
+
+// checkCertExpiration 函数，传递一个域名和超时时间，返回一个切片和错误信息
+func checkCertExpiration(d string, t time.Duration) ([]byte, error) {
+	// 创建 TCP 连接
+	conn, err := net.DialTimeout("tcp", d+":443", t*time.Second)
+	if err != nil {
+		return nil, err
+	}
+	// 函数执行完后关闭连接
+	defer conn.Close()
+
+	// 配置 TLS 的参数，ServerName 为域名，也就是我们调用函数时传递的参数
+	config := &tls.Config{
+		ServerName: d,
+	}
+
+	// 创建一个 TLS 的连接
+	tlsConn := tls.Client(conn, config)
+	// 函数执行完后关闭连接
+	defer tlsConn.Close()
+
+	// 创建一个 TLS 的握手
+	err = tlsConn.Handshake()
+	if err != nil {
+		return nil, err
+	}
+
+	// 获取证书信息，返回的是一个切片
+	certs := tlsConn.ConnectionState().PeerCertificates
+	for _, cert := range certs {
+		info := CertInfo{
+			Domain:    d,
+			Subject:   cert.Subject.CommonName,
+			ExpiresOn: cert.NotAfter.Format("2006-01-02"),
+			DaysLeft:  int(cert.NotAfter.Sub(time.Now()).Hours() / 24),
+		}
+		// 将结构体转换为 JSON 格式
+		return json.Marshal(info)
+	}
+
+	return nil, nil
+}
+
+// handleCheckCertExpiration 函数，处理 HTTP 请求
+func handleCheckCertExpiration(w http.ResponseWriter, r *http.Request) {
+	// 获取 Query 的 domain 参数
+	domain := r.URL.Query().Get("domain")
+	if domain == "" {
+		http.Error(w, "Please provide a domain", http.StatusBadRequest)
+		return
+	}
+
+	// 执行函数并获取返回值
+	data, err := checkCertExpiration(domain, time.Duration(TimeOut))
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+	// 设置响应头
+	w.Header().Set("Content-Type", "application/json")
+	// 写入数据
+	w.Write(data)
+}
+
+// Run 函数，执行函数
+func Run() {
+	// 判断是否开启 HTTP 服务
+	if Weh {
+		http.HandleFunc("/check", handleCheckCertExpiration)
+		err := http.ListenAndServe(Address+":"+Port, nil)
+		if err != nil {
+			return
+		}
+		return
+	}
+
+	// 如果传递的参数为空，打印提示信息
+	if Domain == "" {
+		fmt.Println("Please enter a valid HTTPS link")
+		return
+	}
+
+	// 执行函数并获取返回值
+	data, err := checkCertExpiration(Domain, time.Duration(TimeOut))
+	if err != nil {
+		log.Fatal(err)
+	} else {
+		fmt.Println(string(data))
+	}
+}
diff --git a/cmd/structs.go b/cmd/structs.go
new file mode 100644
index 0000000..e9404c7
--- /dev/null
+++ b/cmd/structs.go
@@ -0,0 +1,8 @@
+package cmd
+
+type CertInfo struct {
+	Domain    string `json:"domain"`
+	Subject   string `json:"subject"`
+	ExpiresOn string `json:"expires_on"`
+	DaysLeft  int    `json:"days_left"`
+}
diff --git a/cmd/vars.go b/cmd/vars.go
new file mode 100644
index 0000000..8e1c0be
--- /dev/null
+++ b/cmd/vars.go
@@ -0,0 +1,9 @@
+package cmd
+
+var (
+	Domain  string
+	TimeOut int
+	Weh     bool
+	Address string
+	Port    string
+)
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..e111095
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module github.com/gitlayzer/tls_check
+
+go 1.22.0
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..210572a
--- /dev/null
+++ b/main.go
@@ -0,0 +1,7 @@
+package main
+
+import "github.com/gitlayzer/tls_check/cmd"
+
+func main() {
+	cmd.Run()
+}