wip: refactor offline download (#5331)

* base tool

* working: aria2

internal/offline_download/aria2/aria2.go

@@ -0,0 +1,73 @@
+package aria2
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/alist-org/alist/v3/internal/conf"
+	"github.com/alist-org/alist/v3/internal/model"
+	"github.com/alist-org/alist/v3/internal/offline_download"
+	"github.com/alist-org/alist/v3/internal/setting"
+	"github.com/alist-org/alist/v3/pkg/aria2/rpc"
+	"github.com/pkg/errors"
+	log "github.com/sirupsen/logrus"
+)
+
+var notify = NewNotify()
+
+type Aria2 struct {
+	client rpc.Client
+}
+
+func (a *Aria2) Items() []model.SettingItem {
+	// aria2 settings
+	return []model.SettingItem{
+		{Key: conf.Aria2Uri, Value: "http://localhost:6800/jsonrpc", Type: conf.TypeString, Group: model.OFFLINE_DOWNLOAD, Flag: model.PRIVATE},
+		{Key: conf.Aria2Secret, Value: "", Type: conf.TypeString, Group: model.OFFLINE_DOWNLOAD, Flag: model.PRIVATE},
+	}
+}
+
+func (a *Aria2) Init() (string, error) {
+	a.client = nil
+	uri := setting.GetStr(conf.Aria2Uri)
+	secret := setting.GetStr(conf.Aria2Secret)
+	c, err := rpc.New(context.Background(), uri, secret, 4*time.Second, notify)
+	if err != nil {
+		return "", errors.Wrap(err, "failed to init aria2 client")
+	}
+	version, err := c.GetVersion()
+	if err != nil {
+		return "", errors.Wrapf(err, "failed get aria2 version")
+	}
+	a.client = c
+	log.Infof("using aria2 version: %s", version.Version)
+	return fmt.Sprintf("aria2 version: %s", version.Version), nil
+}
+
+func (a *Aria2) IsReady() bool {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *Aria2) AddURI(args *offline_download.AddUriArgs) (string, error) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *Aria2) Remove(tid string) error {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *Aria2) Status(tid string) (*offline_download.Status, error) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (a *Aria2) GetFile(tid string) *offline_download.File {
+	//TODO implement me
+	panic("implement me")
+}
+
+var _ offline_download.Tool = (*Aria2)(nil)

internal/offline_download/aria2/notify.go

@@ -0,0 +1,70 @@
+package aria2
+
+import (
+	"github.com/alist-org/alist/v3/pkg/aria2/rpc"
+	"github.com/alist-org/alist/v3/pkg/generic_sync"
+)
+
+const (
+	Downloading = iota
+	Paused
+	Stopped
+	Completed
+	Errored
+)
+
+type Notify struct {
+	Signals generic_sync.MapOf[string, chan int]
+}
+
+func NewNotify() *Notify {
+	return &Notify{Signals: generic_sync.MapOf[string, chan int]{}}
+}
+
+func (n *Notify) OnDownloadStart(events []rpc.Event) {
+	for _, e := range events {
+		if signal, ok := n.Signals.Load(e.Gid); ok {
+			signal <- Downloading
+		}
+	}
+}
+
+func (n *Notify) OnDownloadPause(events []rpc.Event) {
+	for _, e := range events {
+		if signal, ok := n.Signals.Load(e.Gid); ok {
+			signal <- Paused
+		}
+	}
+}
+
+func (n *Notify) OnDownloadStop(events []rpc.Event) {
+	for _, e := range events {
+		if signal, ok := n.Signals.Load(e.Gid); ok {
+			signal <- Stopped
+		}
+	}
+}
+
+func (n *Notify) OnDownloadComplete(events []rpc.Event) {
+	for _, e := range events {
+		if signal, ok := n.Signals.Load(e.Gid); ok {
+			signal <- Completed
+		}
+	}
+}
+
+func (n *Notify) OnDownloadError(events []rpc.Event) {
+	for _, e := range events {
+		if signal, ok := n.Signals.Load(e.Gid); ok {
+			signal <- Errored
+		}
+	}
+}
+
+func (n *Notify) OnBtDownloadComplete(events []rpc.Event) {
+	for _, e := range events {
+		if signal, ok := n.Signals.Load(e.Gid); ok {
+			signal <- Completed
+		}
+	}
+}