패키징 개선

backend/cmd/healthcheck/main.go

@@ -0,0 +1,72 @@
+package main
+
+import (
+	"bufio"
+	"net"
+	"net/url"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+)
+
+func main() {
+	url := strings.TrimSpace(os.Getenv("BACKEND_HEALTHCHECK_URL"))
+	if url == "" {
+		port := strings.TrimSpace(os.Getenv("BACKEND_PORT"))
+		if port == "" {
+			port = strings.TrimSpace(os.Getenv("PORT"))
+		}
+		if port == "" {
+			port = "3000"
+		}
+		url = "http://127.0.0.1:" + port + "/health"
+	}
+
+	statusCode, err := checkHTTP(url, 3*time.Second)
+	if err != nil {
+		_, _ = os.Stderr.WriteString("healthcheck request failed: " + err.Error() + "\n")
+		os.Exit(1)
+	}
+	if statusCode < 200 || statusCode >= 400 {
+		_, _ = os.Stderr.WriteString("healthcheck returned HTTP " + strconv.Itoa(statusCode) + "\n")
+		os.Exit(1)
+	}
+}
+
+func checkHTTP(rawURL string, timeout time.Duration) (int, error) {
+	parsed, err := url.Parse(rawURL)
+	if err != nil {
+		return 0, err
+	}
+	host := parsed.Host
+	if !strings.Contains(host, ":") {
+		host += ":80"
+	}
+	path := parsed.RequestURI()
+	if path == "" {
+		path = "/"
+	}
+
+	conn, err := net.DialTimeout("tcp", host, timeout)
+	if err != nil {
+		return 0, err
+	}
+	defer conn.Close()
+	_ = conn.SetDeadline(time.Now().Add(timeout))
+
+	request := "GET " + path + " HTTP/1.1\r\nHost: " + parsed.Host + "\r\nConnection: close\r\n\r\n"
+	if _, err := conn.Write([]byte(request)); err != nil {
+		return 0, err
+	}
+
+	line, err := bufio.NewReader(conn).ReadString('\n')
+	if err != nil {
+		return 0, err
+	}
+	parts := strings.Fields(line)
+	if len(parts) < 2 {
+		return 0, nil
+	}
+	return strconv.Atoi(parts[1])
+}