scanlib

Documentation

Overview

Package scanlib implements a basic reachability scanner for FFS data blobs, files, and root pointers.

Index

• type Scanner
  • func NewScanner(src blob.CAS) *Scanner
  • func (s *Scanner) AddBareRoot(rootKey string, rp *root.Root)
  • func (s *Scanner) All() iter.Seq2[string, Type]
  • func (s *Scanner) Chunks(n int) iter.Seq[[]string]
  • func (s *Scanner) Data(key string)
  • func (s *Scanner) Has(key string) bool
  • func (s *Scanner) IsRoot(key string) bool
  • func (s *Scanner) Len() int
  • func (s *Scanner) Remove(key string)
  • func (s *Scanner) ScanFile(ctx context.Context, fp *file.File) error
  • func (s *Scanner) ScanRoot(ctx context.Context, rootKey string, rp *root.Root) error
  • func (s *Scanner) Stats() Stats
  • func (s *Scanner) Type(key string) Type
• type Stats
• type Type

Types

type Scanner

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

A Scanner scans all the blobs reachable from a collection of root and file pointers.

func NewScanner

func NewScanner(src blob.CAS) *Scanner

NewScanner creates a new empty Scanner that reads data from src.

func (*Scanner) AddBareRoot

func (s *Scanner) AddBareRoot(rootKey string, rp *root.Root)

AddBareRoot adds the specified root to the scan, including its index (if any), but excluding any blobs reachable from its file or chain pointers.

Use Scanner.ScanRoot to completely scan a root.

func (*Scanner) All

func (s *Scanner) All() iter.Seq2[string, Type]

All returns an iterator over all the key/type pairs in s.

func (*Scanner) Chunks

func (s *Scanner) Chunks(n int) iter.Seq[[]string]

Chunks returns consecutive chunks of the keys in s each having at most n elements and together spanning the complete set of keys recorded. The keys are returned in lexicographic order.

func (*Scanner) Data

func (s *Scanner) Data(key string)

Data adds the specified data blob to s.

func (*Scanner) Has

func (s *Scanner) Has(key string) bool

Has reports whether the specified key is present in s.

func (*Scanner) IsRoot

func (s *Scanner) IsRoot(key string) bool

IsRoot reports whether key is recorded as a root pointer in s.

func (*Scanner) Len

func (s *Scanner) Len() int

Len reports the total number of keys in s, of all kinds.

func (*Scanner) Remove

func (s *Scanner) Remove(key string)

Remove removes the specified key from s.

func (*Scanner) ScanFile

func (s *Scanner) ScanFile(ctx context.Context, fp *file.File) error

AddFile adds all the files and data blobs reachable from fp to s.

func (*Scanner) ScanRoot

func (s *Scanner) ScanRoot(ctx context.Context, rootKey string, rp *root.Root) error

ScanRoot adds the specified root, its index (if any), and all files reachable from its file pointer to s.

func (*Scanner) Stats

func (s *Scanner) Stats() Stats

Stats returns aggregate statistics about everything scanned in s.

func (*Scanner) Type

func (s *Scanner) Type(key string) Type

Type reports the type of the specified key. It panics if key is not in s.

type Stats

type Stats struct {
	NumRoots int // number of distinct roots
	NumFiles int // number of distinct files
	NumBlobs int // number of distinct data blobs
}

Stats records aggregate statistics about a scan.

type Type

type Type byte

Type represents the type of a blob.

const (
	Data  Type = '-' // An unstructured data blob
	File  Type = 'F' // A file record (Node)
	Root  Type = 'R' // A root record (Root)
	Index Type = 'I' // An index record (Index)
	Chain Type = 'C' // A content-addressed root (Root)
)