first commit

backend/internal/api/swap.go

@@ -0,0 +1,189 @@
+package api
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+	"os/exec"
+	"strconv"
+	"strings"
+)
+
+type SwapInfo struct {
+	TotalMB   int64  `json:"total_mb"`
+	UsedMB    int64  `json:"used_mb"`
+	FreeMB    int64  `json:"free_mb"`
+	Enabled   bool   `json:"enabled"`
+	SwapFile  string `json:"swap_file"`
+}
+
+// HandleSwapInfo returns current swap status
+func HandleSwapInfo(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		jsonResponse(w, http.StatusMethodNotAllowed, APIResponse{Success: false, Message: "Method not allowed"})
+		return
+	}
+
+	info := getSwapInfo()
+	jsonResponse(w, http.StatusOK, APIResponse{Success: true, Data: info})
+}
+
+// HandleSwapManage creates/enables/disables swap
+func HandleSwapManage(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		jsonResponse(w, http.StatusMethodNotAllowed, APIResponse{Success: false, Message: "Method not allowed"})
+		return
+	}
+
+	var req struct {
+		Action string `json:"action"` // create, enable, disable, resize
+		SizeMB int    `json:"size_mb"` // for create/resize
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		jsonResponse(w, http.StatusBadRequest, APIResponse{Success: false, Message: "Invalid request body"})
+		return
+	}
+
+	var msg string
+
+	switch req.Action {
+	case "create":
+		if req.SizeMB <= 0 {
+			req.SizeMB = 2048
+		}
+		err := createSwap(req.SizeMB)
+		if err != nil {
+			jsonResponse(w, http.StatusInternalServerError, APIResponse{Success: false, Message: err.Error()})
+			return
+		}
+		msg = fmt.Sprintf("已创建 %d MB SWAP", req.SizeMB)
+
+	case "enable":
+		err := enableSwap()
+		if err != nil {
+			jsonResponse(w, http.StatusInternalServerError, APIResponse{Success: false, Message: err.Error()})
+			return
+		}
+		msg = "SWAP 已启用"
+
+	case "disable":
+		err := disableSwap()
+		if err != nil {
+			jsonResponse(w, http.StatusInternalServerError, APIResponse{Success: false, Message: err.Error()})
+			return
+		}
+		msg = "SWAP 已禁用"
+
+	case "resize":
+		if req.SizeMB <= 0 {
+			jsonResponse(w, http.StatusBadRequest, APIResponse{Success: false, Message: "Invalid size"})
+			return
+		}
+		disableSwap()
+		createSwap(req.SizeMB)
+		enableSwap()
+		msg = fmt.Sprintf("SWAP 已调整为 %d MB", req.SizeMB)
+
+	default:
+		jsonResponse(w, http.StatusBadRequest, APIResponse{Success: false, Message: "Invalid action: " + req.Action})
+		return
+	}
+
+	info := getSwapInfo()
+	jsonResponse(w, http.StatusOK, APIResponse{Success: true, Message: msg, Data: info})
+}
+
+func getSwapInfo() SwapInfo {
+	info := SwapInfo{SwapFile: "/swapfile"}
+
+	// Read /proc/meminfo for swap stats
+	data, err := os.ReadFile("/proc/meminfo")
+	if err != nil {
+		return info
+	}
+
+	lines := strings.Split(string(data), "\n")
+	for _, line := range lines {
+		fields := strings.Fields(line)
+		if len(fields) < 2 {
+			continue
+		}
+		val, _ := strconv.ParseInt(fields[1], 10, 64)
+		switch fields[0] {
+		case "SwapTotal:":
+			info.TotalMB = val / 1024
+		case "SwapFree:":
+			info.FreeMB = val / 1024
+		}
+	}
+
+	info.UsedMB = info.TotalMB - info.FreeMB
+	if info.TotalMB > 0 {
+		info.Enabled = true
+	}
+
+	return info
+}
+
+func createSwap(sizeMB int) error {
+	swapFile := "/swapfile"
+
+	// Check if swap file already exists
+	if _, err := os.Stat(swapFile); err == nil {
+		// Remove old swap file
+		exec.Command("swapoff", swapFile).Run()
+		os.Remove(swapFile)
+	}
+
+	// Create swap file
+	cmd := exec.Command("dd", "if=/dev/zero", "of="+swapFile, "bs=1M", "count="+strconv.Itoa(sizeMB))
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("创建 swap 文件失败: %v, %s", err, string(output))
+	}
+
+	// Set permissions
+	os.Chmod(swapFile, 0600)
+
+	// Make swap
+	cmd = exec.Command("mkswap", swapFile)
+	output, err = cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("mkswap 失败: %v, %s", err, string(output))
+	}
+
+	// Enable swap
+	return enableSwap()
+}
+
+func enableSwap() error {
+	swapFile := "/swapfile"
+	if _, err := os.Stat(swapFile); os.IsNotExist(err) {
+		return fmt.Errorf("swap 文件不存在，请先创建")
+	}
+
+	cmd := exec.Command("swapon", swapFile)
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		// Check if already enabled
+		if strings.Contains(string(output), "already") {
+			return nil
+		}
+		return fmt.Errorf("启用 swap 失败: %v, %s", err, string(output))
+	}
+	return nil
+}
+
+func disableSwap() error {
+	swapFile := "/swapfile"
+	cmd := exec.Command("swapoff", swapFile)
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		if strings.Contains(string(output), "No such") {
+			return nil
+		}
+		return fmt.Errorf("禁用 swap 失败: %v, %s", err, string(output))
+	}
+	return nil
+}