Method loadMergeFiles

engine/merge.go:172–243

Load the merge data directory

()

// Load the merge data directory
func (db *DB) loadMergeFiles() error {
	mergePath := db.getMergePath()
	// Return the merge directory if it does not exist
	if _, err := os.Stat(mergePath); os.IsNotExist(err) {
		return nil
	}
	defer func() {
		_ = os.RemoveAll(mergePath)
	}()

	dirs, err := os.ReadDir(mergePath)

	// Check if there was an error while reading the directory
	if err != nil {
		return err
	}

	// Find the file that identifies the merge and determine whether the merge is complete
	var mergeFinished bool
	var mergeFileNames []string

	// Iterate over the directories
	for _, dir := range dirs {
		// Check if the directory name matches the merge finish file suffix
		if dir.Name() == data2.MergeFinaFileSuffix {
			mergeFinished = true
		}

		// Append the directory name to the mergeFileNames slice
		mergeFileNames = append(mergeFileNames, dir.Name())
	}

	// If not, return directly
	if !mergeFinished {
		return nil
	}

	nonMergeFileID, err := db.getRecentlyNonMergeFileId(mergePath)

	// Check if there was an error while retrieving the recently non-merge file ID
	if err != nil {
		return err
	}

	// Delete old data files
	var fileID uint32 = 0
	for ; fileID < nonMergeFileID; fileID++ {
		fileName := data2.GetDataFileName(db.options.DirPath, fileID)

		// Check if the file exists
		if _, err := os.Stat(fileName); err == nil {
			// Remove the file
			if err := os.Remove(fileName); err != nil {
				return err
			}
		}
	}