middleware

Documentation

Index

• Constants
• Variables
• func CorrelationID(h message.HandlerFunc) message.HandlerFunc
• func InstantAck(h message.HandlerFunc) message.HandlerFunc
• func MessageCorrelationID(message *message.Message) string
• func PoisonQueue(pub message.Publisher, topic string) (message.HandlerMiddleware, error)
• func PoisonQueueWithFilter(pub message.Publisher, topic string, ...) (message.HandlerMiddleware, error)
• func RandomFail(errorRatio float32) message.HandlerMiddleware
• func RandomPanic(panicRatio float32) message.HandlerMiddleware
• func Recoverer(h message.HandlerFunc) message.HandlerFunc
• func SetCorrelationID(id string, msg *message.Message)
• type IgnoreErrors
  • func NewIgnoreErrors(errs []error) IgnoreErrors
  • func (i IgnoreErrors) Middleware(h message.HandlerFunc) message.HandlerFunc
• type OnRetryHook
• type RecoveredPanicError
  • func (p RecoveredPanicError) Error() string
• type Retry
  • func (r Retry) Middleware(h message.HandlerFunc) message.HandlerFunc
• type Throttle
  • func NewThrottle(count int64, duration time.Duration) *Throttle
  • func (t Throttle) Middleware(h message.HandlerFunc) message.HandlerFunc

Constants

const CorrelationIDMetadataKey = "correlation_id"

const RetryForever = -1

Variables

var ErrInvalidPoisonQueueTopic = errors.New("invalid poison queue topic")

ErrInvalidPoisonQueueTopic occurs when the topic supplied to the PoisonQueue constructor is invalid.

var ReasonForPoisonedKey = "reason_poisoned"

ReasonForPoisonedKey is the metadata key which marks the reason (error) why the message was deemed poisoned.

Functions

func CorrelationID

func CorrelationID(h message.HandlerFunc) message.HandlerFunc

CorrelationID adds correlation ID to all messages produced by the handler. ID is based on ID from message received by handler.

To make CorrelationID working correctly, SetCorrelationID must be called to first message entering the system.

func InstantAck

func InstantAck(h message.HandlerFunc) message.HandlerFunc

func MessageCorrelationID

func MessageCorrelationID(message *message.Message) string

MessageCorrelationID returns correlation ID from the message.

func PoisonQueue

func PoisonQueue(pub message.Publisher, topic string) (message.HandlerMiddleware, error)

PoisonQueue provides a middleware that salvages unprocessable messages and published them on a separate topic. The main middleware chain then continues on, business as usual.

func PoisonQueueWithFilter

func PoisonQueueWithFilter(pub message.Publisher, topic string, shouldGoToPoisonQueue func(err error) bool) (message.HandlerMiddleware, error)

func RandomFail

func RandomFail(errorRatio float32) message.HandlerMiddleware

func RandomPanic

func RandomPanic(panicRatio float32) message.HandlerMiddleware

func Recoverer

func Recoverer(h message.HandlerFunc) message.HandlerFunc

func SetCorrelationID

func SetCorrelationID(id string, msg *message.Message)

SetCorrelationID sets a correlation ID for the message.

SetCorrelationID should be called when the message enters the system. When message is produced in a request (for example HTTP), message correlation ID should be the same as the request's correlation ID.

Types

type IgnoreErrors

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

func NewIgnoreErrors

func NewIgnoreErrors(errs []error) IgnoreErrors

func (IgnoreErrors) Middleware

func (i IgnoreErrors) Middleware(h message.HandlerFunc) message.HandlerFunc

type OnRetryHook

type OnRetryHook func(retryNum int, delay time.Duration)

type RecoveredPanicError

type RecoveredPanicError struct {
	V          interface{}
	Stacktrace string
}

func (RecoveredPanicError) Error

func (p RecoveredPanicError) Error() string

type Retry

type Retry struct {
	MaxRetries int

	WaitTime time.Duration
	Backoff  int64

	MaxDelay time.Duration

	OnRetryHook OnRetryHook

	Logger watermill.LoggerAdapter
}

func (Retry) Middleware

func (r Retry) Middleware(h message.HandlerFunc) message.HandlerFunc

type Throttle

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

func NewThrottle

func NewThrottle(count int64, duration time.Duration) *Throttle

NewThrottle creates new Throttle instance. Example duration and count: NewThrottle(10, time.Second) for 10 messages per second

func (Throttle) Middleware

func (t Throttle) Middleware(h message.HandlerFunc) message.HandlerFunc