storage

Documentation

Overview

Package storage implements a simple storage abstraction.

This is meant to abstract filesystem calls, as well as be a wrapper for in-memory or remote storage. It also provides a smaller attack vector as implementations can do verifications as to what is accessed and what is not.

Index

• Variables
• func IsNotExist(err error) bool
• type Bucket
• type ObjectInfo
• type PathError
  • func NewErrNotExist(path string) *PathError
  • func (p *PathError) Error() string
• type ReadBucket
• type ReadObject
• type WriteObject

Variables

var (
	// ErrIncompleteWrite is the error returned if a write is not complete
	ErrIncompleteWrite = errors.New("incomplete write")
	// ErrClosed is the error returned if a bucket or object is already closed.
	ErrClosed = errors.New("already closed")
)

Functions

func IsNotExist

func IsNotExist(err error) bool

IsNotExist returns true for a PathError that is for a path not existing.

Types

type Bucket

type Bucket interface {
	ReadBucket

	// Put returns a WriteCloser to write to the path.
	//
	// The path is truncated beforehand.
	//
	// Returns error on system error.
	Put(ctx context.Context, path string, size uint32) (WriteObject, error)
}

Bucket is a simple read/write bucket.

type ObjectInfo

type ObjectInfo struct {
	Size uint32
}

ObjectInfo is info on an object.

type PathError

type PathError struct {
	Path string
	Err  error
}

PathError is a path error.

func NewErrNotExist

func NewErrNotExist(path string) *PathError

NewErrNotExist returns a new PathError for a path not existing.

func (*PathError) Error

func (p *PathError) Error() string

Error implements error.

type ReadBucket

type ReadBucket interface {
	io.Closer

	// Type returns the type of bucket.
	Type() string
	// Get gets the path.
	//
	// Returns ErrNotExist if the path does not exist, other error
	// if there is a system error.
	Get(ctx context.Context, path string) (ReadObject, error)
	// Stat gets info in the object.
	//
	// Returns ErrNotExist if the path does not exist, other error
	// if there is a system error.
	Stat(ctx context.Context, path string) (ObjectInfo, error)
	// Walk walks the bucket with the prefix, calling f on each path.
	//
	// Note that foo/barbaz will not be called for foo/bar, but will
	// be called for foo/bar/baz.
	//
	// All paths given to f are normalized and validated.
	// If f returns error, Walk will stop short and return this error.
	// Returns other error on system error.
	Walk(ctx context.Context, prefix string, f func(string) error) error
}

ReadBucket is a simple read-only bucket.

All paths regular files - Buckets do not handle directories. All paths must be relative. All paths are cleaned and ToSlash'ed by each function. Paths must not jump the bucket context, that is after clean, they cannot contain "..".

type ReadObject

type ReadObject interface {
	io.ReadCloser

	// Size is the size of the object.
	Size() uint32
}

ReadObject is a read-only object.

It must be closed when done.

type WriteObject

type WriteObject interface {
	io.WriteCloser

	// Size is the size of the object.
	//
	// When closed, the writes must sum up to this size, otherwise ErrIncompleteWrite is returned.
	// Any writes over the size will return io.EOF.
	Size() uint32
}

WriteObject is a write-only object.

It must be closed when done.