WebClient: refactor long-running tasks to improve browser compatibility

Signed-off-by: Nicola Murino <nicola.murino@gmail.com>

internal/httpd/webtask.go

@@ -0,0 +1,108 @@
+// Copyright (C) 2024 Nicola Murino
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published
+// by the Free Software Foundation, version 3.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+package httpd
+
+import (
+	"encoding/json"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/drakkan/sftpgo/v2/internal/dataprovider"
+	"github.com/drakkan/sftpgo/v2/internal/logger"
+	"github.com/drakkan/sftpgo/v2/internal/util"
+)
+
+var (
+	webTaskMgr webTaskManager
+)
+
+func newWebTaskManager(isShared int) webTaskManager {
+	if isShared == 1 {
+		logger.Info(logSender, "", "using provider task manager")
+		return &dbTaskManager{}
+	}
+	logger.Info(logSender, "", "using memory task manager")
+	return &memoryTaskManager{}
+}
+
+type webTaskManager interface {
+	Add(data webTaskData) error
+	Get(ID string) (webTaskData, error)
+	Cleanup()
+}
+
+type webTaskData struct {
+	ID        string `json:"id"`
+	User      string `json:"user"`
+	Path      string `json:"path"`
+	Target    string `json:"target"`
+	Timestamp int64  `json:"ts"`
+	Status    int    `json:"status"` // 0 in progress or http status code (200 ok, 403 and so on)
+}
+
+type memoryTaskManager struct {
+	tasks sync.Map
+}
+
+func (m *memoryTaskManager) Add(data webTaskData) error {
+	m.tasks.Store(data.ID, &data)
+	return nil
+}
+
+func (m *memoryTaskManager) Get(ID string) (webTaskData, error) {
+	data, ok := m.tasks.Load(ID)
+	if !ok {
+		return webTaskData{}, util.NewRecordNotFoundError(fmt.Sprintf("task for ID %q not found", ID))
+	}
+	return *data.(*webTaskData), nil
+}
+
+func (m *memoryTaskManager) Cleanup() {
+	m.tasks.Range(func(key, value any) bool {
+		data := value.(*webTaskData)
+		if data.Timestamp < util.GetTimeAsMsSinceEpoch(time.Now().Add(-5*time.Minute)) {
+			m.tasks.Delete(key)
+		}
+		return true
+	})
+}
+
+type dbTaskManager struct{}
+
+func (m *dbTaskManager) Add(data webTaskData) error {
+	session := dataprovider.Session{
+		Key:       data.ID,
+		Data:      data,
+		Type:      dataprovider.SessionTypeWebTask,
+		Timestamp: data.Timestamp,
+	}
+	return dataprovider.AddSharedSession(session)
+}
+
+func (m *dbTaskManager) Get(ID string) (webTaskData, error) {
+	sess, err := dataprovider.GetSharedSession(ID)
+	if err != nil {
+		return webTaskData{}, err
+	}
+	d := sess.Data.([]byte)
+	var data webTaskData
+	err = json.Unmarshal(d, &data)
+	return data, err
+}
+
+func (m *dbTaskManager) Cleanup() {
+	dataprovider.CleanupSharedSessions(dataprovider.SessionTypeWebTask, time.Now().Add(-5*time.Minute)) //nolint:errcheck
+}