github.com/mckael/restic@v0.8.3/internal/restic/backend.go (about)

     1  package restic
     2  
     3  import (
     4  	"context"
     5  	"io"
     6  )
     7  
     8  // Backend is used to store and access data.
     9  type Backend interface {
    10  	// Location returns a string that describes the type and location of the
    11  	// repository.
    12  	Location() string
    13  
    14  	// Test a boolean value whether a File with the name and type exists.
    15  	Test(ctx context.Context, h Handle) (bool, error)
    16  
    17  	// Remove removes a File described  by h.
    18  	Remove(ctx context.Context, h Handle) error
    19  
    20  	// Close the backend
    21  	Close() error
    22  
    23  	// Save stores the data in the backend under the given handle.
    24  	Save(ctx context.Context, h Handle, rd io.Reader) error
    25  
    26  	// Load runs fn with a reader that yields the contents of the file at h at the
    27  	// given offset. If length is larger than zero, only a portion of the file
    28  	// is read.
    29  	//
    30  	// The function fn may be called multiple times during the same Load invocation
    31  	// and therefore must be idempotent.
    32  	//
    33  	// Implementations are encouraged to use backend.DefaultLoad
    34  	Load(ctx context.Context, h Handle, length int, offset int64, fn func(rd io.Reader) error) error
    35  
    36  	// Stat returns information about the File identified by h.
    37  	Stat(ctx context.Context, h Handle) (FileInfo, error)
    38  
    39  	// List runs fn for each file in the backend which has the type t. When an
    40  	// error occurs (or fn returns an error), List stops and returns it.
    41  	//
    42  	// The function fn is called exactly once for each file during successful
    43  	// execution and at most once in case of an error.
    44  	//
    45  	// The function fn is called in the same Goroutine that List() is called
    46  	// from.
    47  	List(ctx context.Context, t FileType, fn func(FileInfo) error) error
    48  
    49  	// IsNotExist returns true if the error was caused by a non-existing file
    50  	// in the backend.
    51  	IsNotExist(err error) bool
    52  
    53  	// Delete removes all data in the backend.
    54  	Delete(ctx context.Context) error
    55  }
    56  
    57  // FileInfo is contains information about a file in the backend.
    58  type FileInfo struct {
    59  	Size int64
    60  	Name string
    61  }