feat: add copy to task manager

pkg/task/task.go

@@ -0,0 +1,64 @@
+// Package task manage task, such as file upload, file copy between accounts, offline download, etc.
+package task
+
+import (
+	"context"
+	"github.com/pkg/errors"
+)
+
+var (
+	PENDING   = "pending"
+	RUNNING   = "running"
+	FINISHED  = "finished"
+	CANCELING = "canceling"
+	CANCELED  = "canceled"
+)
+
+type Func func(task *Task) error
+
+type Task struct {
+	ID     int64
+	Name   string
+	Status string
+	Error  error
+	Func   Func
+	Ctx    context.Context
+	cancel context.CancelFunc
+}
+
+func newTask(name string, func_ Func) *Task {
+	ctx, cancel := context.WithCancel(context.Background())
+	return &Task{
+		Name:   name,
+		Status: PENDING,
+		Func:   func_,
+		Ctx:    ctx,
+		cancel: cancel,
+	}
+}
+
+func (t *Task) SetStatus(status string) {
+	t.Status = status
+}
+
+func (t *Task) Run() {
+	t.Status = RUNNING
+	t.Error = t.Func(t)
+	if errors.Is(t.Ctx.Err(), context.Canceled) {
+		t.Status = CANCELED
+	} else {
+		t.Status = FINISHED
+	}
+}
+
+func (t *Task) Retry() {
+	t.Run()
+}
+
+func (t *Task) Cancel() {
+	if t.cancel != nil {
+		t.cancel()
+	}
+	// maybe can't cancel
+	t.Status = CANCELING
+}