handlers

Documentation

Index

• type DON
• type Handler
  • func NewDummyHandler(donConfig *config.DONConfig, don DON, lggr logger.Logger) (Handler, error)
• type UserCallbackPayload

Types

type DON

type DON interface {
	// Thread-safe
	SendToNode(ctx context.Context, nodeAddress string, msg *api.Message) error
}

Representation of a DON from a Handler's perspective.

type Handler

type Handler interface {
	job.ServiceCtx

	// Each user request is processed by a separate goroutine, which:
	//   1. calls HandleUserMessage
	//   2. waits on callbackCh with a timeout
	HandleUserMessage(ctx context.Context, msg *api.Message, callbackCh chan<- UserCallbackPayload) error

	// Handlers should not make any assumptions about goroutines calling HandleNodeMessage
	HandleNodeMessage(ctx context.Context, msg *api.Message, nodeAddr string) error
}

Handler implements service-specific logic for managing messages from users and nodes. There is one Handler object created for each DON.

The lifecycle of a Handler object is as follows:

• Start() call
• a series of HandleUserMessage/HandleNodeMessage calls, executed in parallel (Handler needs to guarantee thread safety)
• Close() call

func NewDummyHandler

func NewDummyHandler(donConfig *config.DONConfig, don DON, lggr logger.Logger) (Handler, error)

type UserCallbackPayload

type UserCallbackPayload struct {
	Msg     *api.Message
	ErrCode api.ErrorCode
	ErrMsg  string
}

UserCallbackPayload is a response to user request sent to HandleUserMessage(). Each message needs to receive at most one response on the provided channel.