dynamo-browse/internal/dynamo-browse/services/workspaces/service.go

116 lines
2.9 KiB
Go

package workspaces
import (
"github.com/lmika/audax/internal/dynamo-browse/models"
"github.com/lmika/audax/internal/dynamo-browse/models/serialisable"
"github.com/pkg/errors"
"time"
)
type ViewSnapshotService struct {
store ViewSnapshotStore
}
func NewService(store ViewSnapshotStore) *ViewSnapshotService {
return &ViewSnapshotService{
store: store,
}
}
func (s *ViewSnapshotService) PushSnapshot(rs *models.ResultSet, filter string) error {
newSnapshot := &serialisable.ViewSnapshot{
Time: time.Now(),
TableName: rs.TableInfo.Name,
}
if q := rs.Query; q != nil {
newSnapshot.Query = q.String()
}
newSnapshot.Filter = filter
oldHead, err := s.store.CurrentlyViewedSnapshot()
if err != nil {
return errors.Wrap(err, "cannot get snapshot head")
}
if oldHead != nil {
newSnapshot.BackLink = oldHead.ID
// Remove all nodes from this point on the head
if err := s.store.Dehead(oldHead); err != nil {
return errors.Wrap(err, "cannot remove head")
}
}
if err := s.store.Save(newSnapshot); err != nil {
return errors.Wrap(err, "cannot save snapshot")
}
if oldHead != nil {
oldHead.ForeLink = newSnapshot.ID
if err := s.store.Save(oldHead); err != nil {
return errors.Wrap(err, "cannot update old head")
}
}
if err := s.store.SetAsHead(newSnapshot.ID); err != nil {
return errors.Wrap(err, "cannot set new snapshot as head")
}
if err := s.store.SetCurrentlyViewedSnapshot(newSnapshot.ID); err != nil {
return errors.Wrap(err, "cannot set new snapshot as head")
}
return nil
}
func (s *ViewSnapshotService) ViewRestore() (*serialisable.ViewSnapshot, error) {
vs, err := s.store.CurrentlyViewedSnapshot()
if err != nil {
return nil, errors.Wrap(err, "cannot get snapshot head")
}
return vs, nil
}
func (s *ViewSnapshotService) ViewBack() (*serialisable.ViewSnapshot, error) {
vs, err := s.store.CurrentlyViewedSnapshot()
if err != nil {
return nil, errors.Wrap(err, "cannot get snapshot head")
} else if vs == nil || vs.BackLink == 0 {
return nil, nil
}
vsToReturn, err := s.store.Find(vs.BackLink)
if err != nil {
return nil, errors.Wrap(err, "cannot get snapshot head")
} else if vsToReturn == nil {
return nil, nil
}
if err := s.store.SetCurrentlyViewedSnapshot(vsToReturn.ID); err != nil {
return nil, errors.Wrap(err, "cannot set new head")
}
return vsToReturn, nil
}
func (s *ViewSnapshotService) ViewForward() (*serialisable.ViewSnapshot, error) {
vs, err := s.store.CurrentlyViewedSnapshot()
if err != nil {
return nil, errors.Wrap(err, "cannot get snapshot head")
} else if vs == nil || vs.ForeLink == 0 {
return nil, nil
}
vsToReturn, err := s.store.Find(vs.ForeLink)
if err != nil {
return nil, errors.Wrap(err, "cannot get snapshot head")
} else if vsToReturn == nil {
return nil, nil
}
if err := s.store.SetCurrentlyViewedSnapshot(vsToReturn.ID); err != nil {
return nil, errors.Wrap(err, "cannot set new head")
}
return vsToReturn, nil
}