wal-g

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package internal
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import (
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	"io"
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	"github.com/wal-g/tracelog"
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	"github.com/wal-g/wal-g/internal/multistorage"
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	"github.com/wal-g/wal-g/internal/multistorage/policies"
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	"github.com/wal-g/wal-g/pkg/storages/storage"
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)
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type StorageFolderReader interface {
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	ReadObject(objectRelativePath string) (io.ReadCloser, error)
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	SubFolder(subFolderRelativePath string) StorageFolderReader
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}
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func NewFolderReader(folder storage.Folder) StorageFolderReader {
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	return &FolderReaderImpl{folder}
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}
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type FolderReaderImpl struct {
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	storage.Folder
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}
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func (fsr *FolderReaderImpl) SubFolder(subFolderRelativePath string) StorageFolderReader {
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	return NewFolderReader(fsr.GetSubFolder(subFolderRelativePath))
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}
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func PrepareMultiStorageFolderReader(folder storage.Folder, targetStorage string) (StorageFolderReader, error) {
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	folder = multistorage.SetPolicies(folder, policies.MergeAllStorages)
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	var err error
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	if targetStorage == "" {
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		folder, err = multistorage.UseAllAliveStorages(folder)
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	} else {
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		folder, err = multistorage.UseSpecificStorage(targetStorage, folder)
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	}
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	tracelog.InfoLogger.Printf("Files will be read from storages: %v", multistorage.UsedStorages(folder))
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	if err != nil {
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		return nil, err
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	}
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	return NewFolderReader(folder), nil
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}
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