dataexchange

Documentation

Index

• Constants
• func TypeName(t uint32) string
• func WriteFrame(w io.Writer, f *Frame) error
• func WriteTraceFrame(w io.Writer, tf *TraceFrame) error
• type Client
  • func Dial(d *driver.Driver, addr protocol.Addr) (*Client, error)
  • func (c *Client) Close() error
  • func (c *Client) Recv() (*Frame, error)
  • func (c *Client) SendBinary(data []byte) error
  • func (c *Client) SendFile(name string, data []byte) error
  • func (c *Client) SendJSON(data []byte) error
  • func (c *Client) SendText(text string) error
  • func (c *Client) SendTrace(innerType uint32, data []byte) (sentAtNs int64, err error)
• type Frame
  • func ReadFrame(r io.Reader) (*Frame, error)
• type Handler
• type Server
  • func NewServer(d *driver.Driver, handler Handler) *Server
  • func (s *Server) ListenAndServe() error
• type TraceFrame
  • func ReadTracePayload(f *Frame) (*TraceFrame, error)

Constants

const (
	TypeText   uint32 = 1
	TypeBinary uint32 = 2
	TypeJSON   uint32 = 3
	TypeFile   uint32 = 4
	// TypeTrace wraps another frame type with nanosecond-precision timing.
	// Wire layout: [4-byte TypeTrace][4-byte len][4-byte inner_type][8-byte sent_at_ns][inner_payload]
	TypeTrace uint32 = 5
)

Frame types for data exchange on port 1001.

const MaxFrameSize = 1 << 28

MaxFrameSize caps a single data-exchange frame at 256 MiB. Sized to fit the test fleet's 100 MiB file payloads with margin while still rejecting pathological 500 MiB+ frames that would dominate memory.

Functions

func TypeName

func TypeName(t uint32) string

TypeName returns a human-readable name for a frame type.

func WriteFrame

func WriteFrame(w io.Writer, f *Frame) error

WriteFrame writes a frame to a writer.

func WriteTraceFrame

func WriteTraceFrame(w io.Writer, tf *TraceFrame) error

WriteTraceFrame serialises a TraceFrame as a TypeTrace outer frame.

Types

type Client

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

Client connects to a remote data exchange service on port 1001.

func Dial

func Dial(d *driver.Driver, addr protocol.Addr) (*Client, error)

Dial connects to a remote agent's data exchange port.

func (*Client) Close

func (c *Client) Close() error

Close closes the connection.

func (*Client) Recv

func (c *Client) Recv() (*Frame, error)

Recv reads the next frame from the connection.

func (*Client) SendBinary

func (c *Client) SendBinary(data []byte) error

SendBinary sends a binary frame.

func (*Client) SendFile

func (c *Client) SendFile(name string, data []byte) error

SendFile sends a file frame with a filename and data.

func (*Client) SendJSON

func (c *Client) SendJSON(data []byte) error

SendJSON sends a JSON frame.

func (*Client) SendText

func (c *Client) SendText(text string) error

SendText sends a text frame.

func (*Client) SendTrace

func (c *Client) SendTrace(innerType uint32, data []byte) (sentAtNs int64, err error)

SendTrace wraps data in a TypeTrace frame with the current nanosecond clock. Returns sentAtNs so the caller can correlate it against the timing ACK.

type Frame

type Frame struct {
	Type     uint32
	Payload  []byte
	Filename string // only for TypeFile
}

Frame is a typed data unit exchanged between agents. Wire format: [4-byte type][4-byte length][payload] For TypeFile, payload is: [2-byte name length][name bytes][file data]

func ReadFrame

func ReadFrame(r io.Reader) (*Frame, error)

ReadFrame reads a frame from a reader.

type Handler

type Handler func(conn net.Conn, frame *Frame)

Handler is called for each incoming frame on a connection.

type Server

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

Server listens on port 1001 and dispatches incoming frames to a handler.

func NewServer

func NewServer(d *driver.Driver, handler Handler) *Server

NewServer creates a data exchange server.

func (*Server) ListenAndServe

func (s *Server) ListenAndServe() error

ListenAndServe binds port 1001 and starts accepting connections.

type TraceFrame

type TraceFrame struct {
	SentAtNs  int64
	InnerType uint32
	Payload   []byte
}

TraceFrame carries timing metadata around an inner message frame.

func ReadTracePayload

func ReadTracePayload(f *Frame) (*TraceFrame, error)

ReadTracePayload decodes a TraceFrame from a raw TypeTrace Frame.