metadata

Documentation

Overview

Package metadata defines Metadata of the DataFrame.

Index

• Constants
• type M
  • func Decode(data []byte) (M, error)
  • func New(mds ...map[string]string) M
  • func (m M) Clone() M
  • func (m M) Encode() ([]byte, error)
  • func (m M) Get(k string) (string, bool)
  • func (m M) Range(f func(k, v string) bool)
  • func (m M) Set(k, v string)

Constants

const (
	// the keys for yomo working.
	SourceIDKey = "yomo-source-id"
	TIDKey      = "yomo-tid"

	// the keys for tracing.
	TraceIDKey = "yomo-trace-id"
	SpanIDKey  = "yomo-span-id"

	// the keys for target system working.
	TargetKey       = "yomo-target"
	WantedTargetKey = "yomo-wanted-target"
)

yomo reserved metadata keys.

Types

type M

type M map[string]string

M stores additional information about the application.

There are two types of metadata in yomo:
 1. Metadata from `Authentication.Authenticate()`, This is connection-level metadata.
 2. Metadata from the DataFrame, This is frame-level metadata.

the main responsibility of Metadata is to route messages to connection handler.

func Decode

func Decode(data []byte) (M, error)

Decode decodes a byte array to M.

func New

func New(mds ...map[string]string) M

New creates an M from a given key-values map.

func (M) Clone

func (m M) Clone() M

Clone clones the metadata.

func (M) Encode

func (m M) Encode() ([]byte, error)

Encode encodes the metadata to byte array.

func (M) Get

func (m M) Get(k string) (string, bool)

Get returns the value of the given key.

func (M) Range

func (m M) Range(f func(k, v string) bool)

Range iterates over all keys and values.

func (M) Set

func (m M) Set(k, v string)

Set sets the value of the given key. if the key is empty, it will do nothing.