accessor

Documentation

Overview

Package accessor provides random access to pxar archives.

Index

• type Accessor
  • func NewAccessor(reader io.ReadSeeker, payloadReader ...io.ReadSeeker) *Accessor
  • func (a *Accessor) ListDirectory(dirOffset int64) ([]pxar.Entry, error)
  • func (a *Accessor) ListDirectoryWithOptions(dirOffset int64, opts ListOption) ([]pxar.Entry, error)
  • func (a *Accessor) Lookup(path string) (*pxar.Entry, error)
  • func (a *Accessor) LookupBatch(paths []string) ([]*pxar.Entry, error)
  • func (a *Accessor) ReadEntryAt(offset int64) (*pxar.Entry, error)
  • func (a *Accessor) ReadEntryAtMinimal(offset int64) (*pxar.Entry, error)
  • func (a *Accessor) ReadFileContent(entry *pxar.Entry) ([]byte, error)
  • func (a *Accessor) ReadFileContentReader(entry *pxar.Entry) (io.ReadCloser, error)
  • func (a *Accessor) ReadRoot() (*pxar.Entry, error)
• type ListOption

Types

type Accessor

type Accessor struct {
	// contains filtered or unexported fields
}

Accessor provides random access to entries in a pxar archive.

func NewAccessor

func NewAccessor(reader io.ReadSeeker, payloadReader ...io.ReadSeeker) *Accessor

NewAccessor creates an accessor for random access to a pxar archive. For split archives (v2 format), provide the payload reader as the second argument.

func (*Accessor) ListDirectory

func (a *Accessor) ListDirectory(dirOffset int64) ([]pxar.Entry, error)

ListDirectory lists entries in a directory at the given offset. The offset should point to the start of the directory's FILENAME range.

func (*Accessor) ListDirectoryWithOptions

func (a *Accessor) ListDirectoryWithOptions(dirOffset int64, opts ListOption) ([]pxar.Entry, error)

ListDirectoryWithOptions lists entries with selective metadata decoding. When opts.Minimal is true, extended metadata (xattrs, fcaps, ACLs) is skipped — only stat basics are decoded.

func (*Accessor) Lookup

func (a *Accessor) Lookup(path string) (*pxar.Entry, error)

Lookup finds an entry by path in the archive.

func (*Accessor) LookupBatch

func (a *Accessor) LookupBatch(paths []string) ([]*pxar.Entry, error)

LookupBatch looks up multiple paths in a single pass. It is more efficient than N separate Lookup calls because it shares directory traversals for common prefixes.

func (*Accessor) ReadEntryAt

func (a *Accessor) ReadEntryAt(offset int64) (*pxar.Entry, error)

ReadEntryAt reads a pxar entry at the given archive offset.

func (*Accessor) ReadEntryAtMinimal

func (a *Accessor) ReadEntryAtMinimal(offset int64) (*pxar.Entry, error)

ReadEntryAtMinimal reads a pxar entry with minimal decoding. It skips extended metadata (xattrs, fcaps, ACLs, quota project ID) and only populates stat basics. Use for indexing/browsing where full metadata is unnecessary.

func (*Accessor) ReadFileContent

func (a *Accessor) ReadFileContent(entry *pxar.Entry) ([]byte, error)

ReadFileContent reads the content of a file entry from the archive.

func (*Accessor) ReadFileContentReader

func (a *Accessor) ReadFileContentReader(entry *pxar.Entry) (io.ReadCloser, error)

ReadFileContentReader returns a streaming reader for file content. The caller must close the returned reader when done. This avoids materializing the entire file in memory.

When the underlying reader implements io.ReaderAt, the returned reader is backed by an io.SectionReader and is safe for concurrent use across multiple goroutines (each call returns an independent reader).

func (*Accessor) ReadRoot

func (a *Accessor) ReadRoot() (*pxar.Entry, error)

ReadRoot reads the root entry of the archive.

type ListOption

type ListOption struct {
	// Minimal skips decoding xattrs, fcaps, ACLs, and other extended
	// metadata. Only stat basics (mode, uid, gid, times) are populated.
	// Significantly reduces per-entry decode cost.
	Minimal bool
}

ListOption controls which metadata is decoded during ListDirectory.