Feat: download file from single file share

models/group.go

@@ -25,10 +25,11 @@ type Group struct {
 
 // GroupOption 用户组其他配置
 type GroupOption struct {
-	ArchiveDownloadEnabled bool `json:"archive_download"`
-	ArchiveTaskEnabled     bool `json:"archive_task"`
-	OneTimeDownloadEnabled bool `json:"one_time_download"`
-	ShareDownloadEnabled   bool `json:"share_download"`
+	ArchiveDownloadEnabled bool `json:"archive_download,omitempty"`
+	ArchiveTaskEnabled     bool `json:"archive_task,omitempty"`
+	OneTimeDownloadEnabled bool `json:"one_time_download,omitempty"`
+	ShareDownloadEnabled   bool `json:"share_download,omitempty"`
+	ShareFreeEnabled       bool `json:"share_free,omitempty"`
 }
 
 // GetAria2Option 获取用户离线下载设备

models/migration.go

@@ -108,6 +108,7 @@ solid #e9e9e9;"bgcolor="#fff"><tbody><tr style="font-family: 'Helvetica Neue',He
 		{Name: "upload_session_timeout", Value: `86400`, Type: "timeout"},
 		{Name: "slave_api_timeout", Value: `60`, Type: "timeout"},
 		{Name: "onedrive_monitor_timeout", Value: `600`, Type: "timeout"},
+		{Name: "share_download_session_timeout", Value: `2073600`, Type: "timeout"},
 		{Name: "onedrive_callback_check", Value: `20`, Type: "timeout"},
 		{Name: "onedrive_chunk_retries", Value: `1`, Type: "retry"},
 		{Name: "allowdVisitorDownload", Value: `false`, Type: "share"},
@@ -185,6 +186,7 @@ func addDefaultGroups() {
 			OptionsSerialized: GroupOption{
 				ArchiveDownloadEnabled: true,
 				ArchiveTaskEnabled:     true,
+				ShareDownloadEnabled:   true,
 			},
 		}
 		if err := DB.Create(&defaultAdminGroup).Error; err != nil {

models/share.go

@@ -1,6 +1,9 @@
 package model
 
 import (
+	"errors"
+	"fmt"
+	"github.com/HFO4/cloudreve/pkg/cache"
 	"github.com/HFO4/cloudreve/pkg/hashid"
 	"github.com/HFO4/cloudreve/pkg/util"
 	"github.com/jinzhu/gorm"
@@ -86,6 +89,14 @@ func (share *Share) GetCreator() *User {
 	return &share.User
 }
 
+// GetSource 返回源对象
+func (share *Share) GetSource() interface{} {
+	if share.IsDir {
+		return share.GetSourceFolder()
+	}
+	return share.GetSourceFile()
+}
+
 // GetSourceFolder 获取源目录
 func (share *Share) GetSourceFolder() *Folder {
 	if share.Folder.ID == 0 {
@@ -107,3 +118,69 @@ func (share *Share) GetSourceFile() *File {
 	}
 	return &share.File
 }
+
+// CanBeDownloadBy 返回此分享是否可以被给定用户下载
+func (share *Share) CanBeDownloadBy(user *User) error {
+	// 用户组权限
+	if !user.Group.OptionsSerialized.ShareDownloadEnabled {
+		if user.IsAnonymous() {
+			return errors.New("未登录用户无法下载")
+		}
+		return errors.New("您当前的用户组无权下载")
+	}
+
+	// 需要积分但未登录
+	if share.Score > 0 && user.IsAnonymous() {
+		return errors.New("未登录用户无法下载")
+	}
+
+	return nil
+}
+
+// WasDownloadedBy 返回分享是否已被用户下载过
+func (share *Share) WasDownloadedBy(user *User) bool {
+	_, exist := cache.Get(fmt.Sprintf("share_%d_%d", share.ID, user.ID))
+	return exist
+}
+
+// DownloadBy 增加下载次数、检查积分等，匿名用户不会缓存
+func (share *Share) DownloadBy(user *User) error {
+	if !share.WasDownloadedBy(user) {
+		if err := share.Purchase(user); err != nil {
+			return err
+		}
+		share.Downloaded()
+		if !user.IsAnonymous() {
+			cache.Set(fmt.Sprintf("share_%d_%d", share.ID, user.ID), true,
+				GetIntSetting("share_download_session_timeout", 2073600))
+		}
+	}
+	return nil
+}
+
+// Purchase 使用积分购买分享
+func (share *Share) Purchase(user *User) error {
+	// 不需要付积分
+	if share.Score == 0 || user.Group.OptionsSerialized.ShareFreeEnabled {
+		return nil
+	}
+
+	ok := user.PayScore(share.Score)
+	if !ok {
+		return errors.New("积分不足")
+	}
+
+	return nil
+}
+
+// Viewed 增加访问次数
+func (share *Share) Viewed() {
+	share.Views++
+	DB.Model(share).UpdateColumn("views", gorm.Expr("views + ?", 1))
+}
+
+// Downloaded 增加下载次数
+func (share *Share) Downloaded() {
+	share.Downloads++
+	DB.Model(share).UpdateColumn("downloads", gorm.Expr("downloads + ?", 1))
+}

models/user.go

@@ -39,6 +39,7 @@ type User struct {
 	Avatar        string
 	Options       string `json:"-",gorm:"size:4096"`
 	Authn         string `gorm:"size:8192"`
+	Score         int
 
 	// 关联模型
 	Group  Group  `gorm:"association_autoupdate:false"`
@@ -93,6 +94,20 @@ func (user *User) IncreaseStorage(size uint64) bool {
 	return false
 }
 
+// PayScore 扣除积分，返回是否成功
+// todo 测试
+func (user *User) PayScore(score int) bool {
+	if score == 0 {
+		return true
+	}
+	if score <= user.Score {
+		user.Score -= score
+		DB.Model(user).UpdateColumn("score", gorm.Expr("score - ?", score))
+		return true
+	}
+	return false
+}
+
 // IncreaseStorageWithoutCheck 忽略可用容量，增加用户已用容量
 func (user *User) IncreaseStorageWithoutCheck(size uint64) {
 	if size == 0 {