iomeshage

Documentation

Overview

iomeshage is a file transfer layer for meshage

Files are stored in a predetermined directory structure. When a particular meshage node needs a file, it polls nodes looking for that file, looking at shortest path nodes first. The node with the file and the fewest hops will transfer the file to the requesting node.

Index

• Constants
• type FileInfo
• type IOMeshage
  • func New(base string, node *meshage.Node) (*IOMeshage, error)
  • func (iom *IOMeshage) Delete(path string) error
  • func (iom *IOMeshage) Get(file string) error
  • func (iom *IOMeshage) Info(file string) []string
  • func (iom *IOMeshage) List(path string, recurse bool) ([]FileInfo, error)
  • func (iom *IOMeshage) MITM(m *Message)
  • func (iom *IOMeshage) Rel(info FileInfo) string
  • func (iom *IOMeshage) Status() []*Transfer
  • func (iom *IOMeshage) Stream(file string) (chan []byte, error)
• type Message
• type MessageType
  • func (m MessageType) String() string
• type Transfer

Constants

const (
	MAX_ATTEMPTS = 3
	QUEUE_LEN    = 3
)

const (
	PART_SIZE = 10485760 // 10MB
)

Types

type FileInfo

type FileInfo struct {
	// Path is the absolute path to the file
	Path string

	// Size of the file
	Size int64

	// embed
	os.FileMode
}

FileInfo object. Used by the calling API to describe existing files.

type IOMeshage

type IOMeshage struct {
	Messages chan *meshage.Message // Incoming messages from meshage

	TIDs map[int64]chan *Message // transfer ID -> channel
	// contains filtered or unexported fields
}

IOMeshage object, which must have a base path to serve files on and a meshage node.

func New

func New(base string, node *meshage.Node) (*IOMeshage, error)

New returns a new iomeshage object service base directory via meshage

func (*IOMeshage) Delete

func (iom *IOMeshage) Delete(path string) error

Delete a file or directory on the local node. Supports Globs.

func (*IOMeshage) Get

func (iom *IOMeshage) Get(file string) error

Retrieve a file from the shortest path node that has it. Get blocks until the file transfer begins or errors out. If the file specified is a directory, the entire directory will be recursively transferred. If the file already exists on this node, Get will return immediately with no error.

func (*IOMeshage) Info

func (iom *IOMeshage) Info(file string) []string

search the mesh for the file/glob/directory, returning a slice of string matches. The search includes local matches.

func (*IOMeshage) List

func (iom *IOMeshage) List(path string, recurse bool) ([]FileInfo, error)

List files and directories on the local node. List on a file returns the info for that file only. List on a directory returns the contents of that directory. Supports expanding globs. When recursive is true, reports all files and directories below the specified path(s).

func (*IOMeshage) MITM

func (iom *IOMeshage) MITM(m *Message)

Check iom messages that are routing through us in case it's a filepart that we're also looking for. If so, write it out. The message mux for meshage should call this.

func (*IOMeshage) Rel

func (iom *IOMeshage) Rel(info FileInfo) string

func (*IOMeshage) Status

func (iom *IOMeshage) Status() []*Transfer

Status returns a deep copy of the in-flight file transfers

func (*IOMeshage) Stream

func (iom *IOMeshage) Stream(file string) (chan []byte, error)

Stream requests each part of the file in order, returning a channel to read the parts from. This does not store the file locally to avoid filling up the local disk.

type Message

type Message struct {
	// Type of message
	Type MessageType

	From     string
	Filename string
	Perm     os.FileMode
	Glob     []string
	Part     int64
	TID      int64
	ACK      bool
	Data     []byte
}

Message is the only structure sent between iomeshage nodes (including ACKS). It is used as the body of a meshage message.

type MessageType

type MessageType int

const (
	TYPE_INFO MessageType = iota
	TYPE_WHOHAS
	TYPE_XFER
	TYPE_RESPONSE
)

func (MessageType) String

func (m MessageType) String() string

type Transfer

type Transfer struct {
	Dir      string         // temporary directory hold the file parts
	Filename string         // file name
	Parts    map[int64]bool // completed parts
	NumParts int            // total number of parts for this file
	Inflight int64          // currently in-flight part, -1 if none
	Queued   bool
}

Transfer describes an in-flight transfer.