Documentation
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Overview ¶
Package nats provides a NATS transport.
Index ¶
- func DefaultErrorEncoder(_ context.Context, err error, reply string, nc *nats.Conn)
- func EncodeJSONRequest(_ context.Context, msg *nats.Msg, request interface{}) error
- func EncodeJSONResponse(_ context.Context, reply string, nc *nats.Conn, response interface{}) error
- func NopRequestDecoder(_ context.Context, _ *nats.Msg) (interface{}, error)
- type DecodeRequestFunc
- type DecodeResponseFunc
- type EncodeRequestFunc
- type EncodeResponseFunc
- type ErrorEncoder
- type Publisher
- type PublisherOption
- type PublisherResponseFunc
- type RequestFunc
- type Subscriber
- type SubscriberFinalizerFunc
- type SubscriberOption
- func SubscriberAfter(after ...SubscriberResponseFunc) SubscriberOption
- func SubscriberBefore(before ...RequestFunc) SubscriberOption
- func SubscriberErrorEncoder(ee ErrorEncoder) SubscriberOption
- func SubscriberErrorLogger(logger log.Logger) SubscriberOption
- func SubscriberFinalizer(f ...SubscriberFinalizerFunc) SubscriberOption
- type SubscriberResponseFunc
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func DefaultErrorEncoder ¶
DefaultErrorEncoder writes the error to the subscriber reply.
func EncodeJSONRequest ¶
EncodeJSONRequest is an EncodeRequestFunc that serializes the request as a JSON object to the Data of the Msg. Many JSON-over-NATS services can use it as a sensible default.
func EncodeJSONResponse ¶
EncodeJSONResponse is a EncodeResponseFunc that serializes the response as a JSON object to the subscriber reply. Many JSON-over services can use it as a sensible default.
func NopRequestDecoder ¶
NopRequestDecoder is a DecodeRequestFunc that can be used for requests that do not need to be decoded, and simply returns nil, nil.
Types ¶
type DecodeRequestFunc ¶
DecodeRequestFunc extracts a user-domain request object from a publisher request object. It's designed to be used in NATS subscribers, for subscriber-side endpoints. One straightforward DecodeRequestFunc could be something that JSON decodes from the request body to the concrete response type.
type DecodeResponseFunc ¶
DecodeResponseFunc extracts a user-domain response object from an NATS response object. It's designed to be used in NATS publisher, for publisher-side endpoints. One straightforward DecodeResponseFunc could be something that JSON decodes from the response payload to the concrete response type.
type EncodeRequestFunc ¶
EncodeRequestFunc encodes the passed request object into the NATS request object. It's designed to be used in NATS publishers, for publisher-side endpoints. One straightforward EncodeRequestFunc could something that JSON encodes the object directly to the request payload.
type EncodeResponseFunc ¶
EncodeResponseFunc encodes the passed response object to the subscriber reply. It's designed to be used in NATS subscribers, for subscriber-side endpoints. One straightforward EncodeResponseFunc could be something that JSON encodes the object directly to the response body.
type ErrorEncoder ¶
ErrorEncoder is responsible for encoding an error to the subscriber reply. Users are encouraged to use custom ErrorEncoders to encode errors to their replies, and will likely want to pass and check for their own error types.
type Publisher ¶
type Publisher struct {
// contains filtered or unexported fields
}
Publisher wraps a URL and provides a method that implements endpoint.Endpoint.
func NewPublisher ¶
func NewPublisher( publisher *nats.Conn, subject string, enc EncodeRequestFunc, dec DecodeResponseFunc, options ...PublisherOption, ) *Publisher
NewPublisher constructs a usable Publisher for a single remote method.
type PublisherOption ¶
type PublisherOption func(*Publisher)
PublisherOption sets an optional parameter for clients.
func PublisherAfter ¶
func PublisherAfter(after ...PublisherResponseFunc) PublisherOption
PublisherAfter sets the ClientResponseFuncs applied to the incoming NATS request prior to it being decoded. This is useful for obtaining anything off of the response and adding onto the context prior to decoding.
func PublisherBefore ¶
func PublisherBefore(before ...RequestFunc) PublisherOption
PublisherBefore sets the RequestFuncs that are applied to the outgoing NATS request before it's invoked.
func PublisherTimeout ¶
func PublisherTimeout(timeout time.Duration) PublisherOption
PublisherTimeout sets the available timeout for NATS request.
type PublisherResponseFunc ¶
PublisherResponseFunc may take information from an NATS request and make the response available for consumption. ClientResponseFuncs are only executed in clients, after a request has been made, but prior to it being decoded.
type RequestFunc ¶
RequestFunc may take information from a publisher request and put it into a request context. In Subscribers, RequestFuncs are executed prior to invoking the endpoint.
type Subscriber ¶
type Subscriber struct {
// contains filtered or unexported fields
}
Subscriber wraps an endpoint and provides nats.MsgHandler.
func NewSubscriber ¶
func NewSubscriber( e endpoint.Endpoint, dec DecodeRequestFunc, enc EncodeResponseFunc, options ...SubscriberOption, ) *Subscriber
NewSubscriber constructs a new subscriber, which provides nats.MsgHandler and wraps the provided endpoint.
func (Subscriber) ServeMsg ¶
func (s Subscriber) ServeMsg(nc *nats.Conn) func(msg *nats.Msg)
ServeMsg provides nats.MsgHandler.
type SubscriberFinalizerFunc ¶
ServerFinalizerFunc can be used to perform work at the end of an request from a publisher, after the response has been written to the publisher. The principal intended use is for request logging.
type SubscriberOption ¶
type SubscriberOption func(*Subscriber)
SubscriberOption sets an optional parameter for subscribers.
func SubscriberAfter ¶
func SubscriberAfter(after ...SubscriberResponseFunc) SubscriberOption
SubscriberAfter functions are executed on the subscriber reply after the endpoint is invoked, but before anything is published to the reply.
func SubscriberBefore ¶
func SubscriberBefore(before ...RequestFunc) SubscriberOption
SubscriberBefore functions are executed on the publisher request object before the request is decoded.
func SubscriberErrorEncoder ¶
func SubscriberErrorEncoder(ee ErrorEncoder) SubscriberOption
SubscriberErrorEncoder is used to encode errors to the subscriber reply whenever they're encountered in the processing of a request. Clients can use this to provide custom error formatting. By default, errors will be published with the DefaultErrorEncoder.
func SubscriberErrorLogger ¶
func SubscriberErrorLogger(logger log.Logger) SubscriberOption
SubscriberErrorLogger is used to log non-terminal errors. By default, no errors are logged. This is intended as a diagnostic measure. Finer-grained control of error handling, including logging in more detail, should be performed in a custom SubscriberErrorEncoder which has access to the context.
func SubscriberFinalizer ¶
func SubscriberFinalizer(f ...SubscriberFinalizerFunc) SubscriberOption
SubscriberFinalizer is executed at the end of every request from a publisher through NATS. By default, no finalizer is registered.
type SubscriberResponseFunc ¶
SubscriberResponseFunc may take information from a request context and use it to manipulate a Publisher. SubscriberResponseFuncs are only executed in subscribers, after invoking the endpoint but prior to publishing a reply.
Source Files