Add sync logic and execution

sync/db.go

@@ -29,6 +29,16 @@ func (s *Sync) initSchema() error {
 	return err
 }
 
+func (s *Sync) deleteDBFileInfo(side, relativeName string) error {
+	stmt, err := s.db.Prepare(fmt.Sprintf(`DELETE FROM %s_state WHERE relative_name = ?`, side))
+	if err != nil {
+		return errors.Wrap(err, "Unable to prepare query")
+	}
+
+	_, err = stmt.Exec(relativeName)
+	return errors.Wrap(err, "Unable to delete file info")
+}
+
 func (s *Sync) getDBFileInfo(side, relativeName string) (providers.FileInfo, error) {
 	info := providers.FileInfo{}
 
@@ -48,7 +58,7 @@ func (s *Sync) getDBFileInfo(side, relativeName string) (providers.FileInfo, err
 	return info, nil
 }
 
-func (s *Sync) setDBFileInfo(side, info providers.FileInfo) error {
+func (s *Sync) setDBFileInfo(side string, info providers.FileInfo) error {
 	stmt, err := s.db.Prepare(fmt.Sprintf(
 		`INSERT INTO %s_state VALUES(?, ?, ?, ?) 
 			ON CONFLICT(relative_name) DO UPDATE SET 

sync/execute.go

@@ -0,0 +1,45 @@
+package sync
+
+import (
+	"github.com/pkg/errors"
+
+	"github.com/Luzifer/cloudbox/providers"
+)
+
+func (s *Sync) deleteFile(on providers.CloudProvider, fileName string) error {
+	if err := on.DeleteFile(fileName); err != nil {
+		return errors.Wrap(err, "Unable to delete file")
+	}
+
+	if err := s.deleteDBFileInfo(sideLocal, fileName); err != nil {
+		return errors.Wrap(err, "Umable to delete local file info")
+	}
+
+	if err := s.deleteDBFileInfo(sideRemote, fileName); err != nil {
+		return errors.Wrap(err, "Umable to delete remote file info")
+	}
+
+	return nil
+}
+
+func (s *Sync) transferFile(from, to providers.CloudProvider, sideFrom, sideTo, fileName string) error {
+	file, err := from.GetFile(fileName)
+	if err != nil {
+		return errors.Wrap(err, "Unable to retrieve file")
+	}
+
+	newFile, err := to.PutFile(file)
+	if err != nil {
+		return errors.Wrap(err, "Unable to put file")
+	}
+
+	if err := s.setDBFileInfo(sideTo, newFile.Info()); err != nil {
+		return errors.Wrap(err, "Unable to update DB info for target file")
+	}
+
+	if err := s.setDBFileInfo(sideFrom, file.Info()); err != nil {
+		return errors.Wrap(err, "Unable to update DB info for source file")
+	}
+
+	return nil
+}

sync/logic.go

@@ -0,0 +1,61 @@
+package sync
+
+import log "github.com/sirupsen/logrus"
+
+func (s *Sync) decideAction(syncState *state, fileName string) error {
+	var (
+		change = syncState.GetChangeFor(fileName)
+		logger = log.WithField("filename", fileName)
+	)
+
+	switch {
+	case !change.Changed():
+		// No changes at all: Get out of here
+		logger.Debug("File in sync")
+		return nil
+
+	case change.HasAll(ChangeLocalUpdate, ChangeRemoteUpdate):
+		// We do have local and remote changes: Check both are now the same or leave this to manual resolve
+		logger.Warn("File has local and remote updates, sync not possible")
+
+	case change.HasAll(ChangeLocalAdd, ChangeRemoteAdd):
+		// Special case: Both are added, check thet are the same file or break
+		logger.Debug("File added locally as well as remotely")
+		// TODO: Handle special case
+
+	case change.HasAll(ChangeLocalDelete, ChangeRemoteDelete):
+		// Special case: Both vanished, we just need to clean up the sync cache
+		logger.Debug("File deleted locally as well as remotely")
+		// TODO: Handle special case
+
+	case change.Is(ChangeLocalAdd) || change.Is(ChangeLocalUpdate):
+		logger.Debug("File added or changed locally, uploading...")
+		if err := s.transferFile(s.local, s.remote, sideLocal, sideRemote, fileName); err != nil {
+			logger.WithError(err).Error("Unable to upload file")
+		}
+
+	case change.Is(ChangeLocalDelete):
+		logger.Debug("File deleted locally, removing from remote...")
+		if err := s.deleteFile(s.remote, fileName); err != nil {
+			logger.WithError(err).Error("Unable to delete file from remote")
+		}
+
+	case change.Is(ChangeRemoteAdd) || change.Is(ChangeRemoteUpdate):
+		logger.Debug("File added or changed remotely, downloading...")
+		if err := s.transferFile(s.remote, s.local, sideRemote, sideLocal, fileName); err != nil {
+			logger.WithError(err).Error("Unable to download file")
+		}
+
+	case change.Is(ChangeRemoteDelete):
+		logger.Debug("File deleted remotely, removing from local...")
+		if err := s.deleteFile(s.local, fileName); err != nil {
+			logger.WithError(err).Error("Unable to delete file from local")
+		}
+
+	default:
+		// Unhandled case
+		logger.WithField("change", change).Warn("Unhandled change case")
+	}
+
+	return nil
+}

sync/state.go

@@ -27,6 +27,16 @@ func (c *Change) Register(add Change) {
 	*c = *c | add
 }
 
+func (c Change) HasAll(test ...Change) bool {
+	for _, t := range test {
+		if c&t == 0 {
+			return false
+		}
+	}
+
+	return true
+}
+
 func (c Change) HasOne(test ...Change) bool {
 	for _, t := range test {
 		if c&t != 0 {

sync/sync.go

@@ -103,8 +103,11 @@ func (s *Sync) runSync() error {
 		return errors.Wrap(err, "Unable to load remote files")
 	}
 
-	// TODO: Do something with sync database
-	s.log.Printf("%#v", syncState)
+	for _, fileName := range syncState.GetRelativeNames() {
+		if err := s.decideAction(syncState, fileName); err != nil {
+			return errors.Wrap(err, "Could not execute sync")
+		}
+	}
 
 	return nil
 }