refactor virtual folders

The same virtual folder can now be shared among users and different
folder quota limits for each user are supported.

Fixes #120

vfs/folder.go

@@ -0,0 +1,71 @@
+package vfs
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"github.com/drakkan/sftpgo/utils"
+)
+
+// BaseVirtualFolder defines the path for the virtual folder and the used quota limits.
+// The same folder can be shared among multiple users and each user can have different
+// quota limits or a different virtual path.
+type BaseVirtualFolder struct {
+	ID            int64  `json:"id"`
+	MappedPath    string `json:"mapped_path"`
+	UsedQuotaSize int64  `json:"used_quota_size"`
+	// Used quota as number of files
+	UsedQuotaFiles int `json:"used_quota_files"`
+	// Last quota update as unix timestamp in milliseconds
+	LastQuotaUpdate int64 `json:"last_quota_update"`
+	// list of usernames associated with this virtual folder
+	Users []string `json:"users,omitempty"`
+}
+
+// GetUsersAsString returns the list of users as comma separated string
+func (v *BaseVirtualFolder) GetUsersAsString() string {
+	return strings.Join(v.Users, ",")
+}
+
+// GetQuotaSummary returns used quota and last update as string
+func (v *BaseVirtualFolder) GetQuotaSummary() string {
+	var result string
+	result = "Files: " + strconv.Itoa(v.UsedQuotaFiles)
+	if v.UsedQuotaSize > 0 {
+		result += ". Size: " + utils.ByteCountSI(v.UsedQuotaSize)
+	}
+	if v.LastQuotaUpdate > 0 {
+		t := utils.GetTimeFromMsecSinceEpoch(v.LastQuotaUpdate)
+		result += fmt.Sprintf(". Last update: %v ", t.Format("2006-01-02 15:04:05")) // YYYY-MM-DD HH:MM:SS
+	}
+	return result
+}
+
+// VirtualFolder defines a mapping between a SFTP/SCP virtual path and a
+// filesystem path outside the user home directory.
+// The specified paths must be absolute and the virtual path cannot be "/",
+// it must be a sub directory. The parent directory for the specified virtual
+// path must exist. SFTPGo will try to automatically create any missing
+// parent directory for the configured virtual folders at user login.
+type VirtualFolder struct {
+	BaseVirtualFolder
+	VirtualPath string `json:"virtual_path"`
+	// Maximum size allowed as bytes. 0 means unlimited, -1 included in user quota
+	QuotaSize int64 `json:"quota_size"`
+	// Maximum number of files allowed. 0 means unlimited, -1 included in user quota
+	QuotaFiles int `json:"quota_files"`
+}
+
+// IsIncludedInUserQuota returns true if the virtual folder is included in user quota
+func (v *VirtualFolder) IsIncludedInUserQuota() bool {
+	return v.QuotaFiles == -1 && v.QuotaSize == -1
+}
+
+// HasNoQuotaRestrictions returns true if no quota restrictions need to be applyed
+func (v *VirtualFolder) HasNoQuotaRestrictions(checkFiles bool) bool {
+	if v.QuotaSize == 0 && (!checkFiles || v.QuotaFiles == 0) {
+		return true
+	}
+	return false
+}