kitDefaults

Documentation

Index

• Constants
• func DefaultErrorEncoder(_ context.Context, err error, w http.ResponseWriter)
• func DefaultHttpErrorEncoder(_ context.Context, err error, w http.ResponseWriter)
• func DefaultHttpResponseEncoder(ctx context.Context, w http.ResponseWriter, response interface{}) error
• func EncodeJSONResponse(_ context.Context, w http.ResponseWriter, response interface{}) error
• func Nop(context.Context, interface{}) (interface{}, error)
• func NopRequestDecoder(ctx context.Context, r *http.Request) (interface{}, error)
• func PopulateRequestContext(ctx context.Context, r *http.Request) context.Context
• type ClientResponseFunc
• type CodedError
• type DecodeRequestFunc
• type EncodeResponseFunc
• type Endpoint
• type ErrorEncoder
• type ErrorHandler
• type ErrorHandlerFunc
  • func (f ErrorHandlerFunc) Handle(ctx context.Context, err error)
• type Failer
• type Headerer
• type HttpCoder
• type LogErrorHandler
  • func NewLogErrorHandler(logger log.Logger) *LogErrorHandler
  • func (h *LogErrorHandler) Handle(ctx context.Context, err error)
• type Middleware
• type RequestFunc
  • func SetRequestHeader(key, val string) RequestFunc
• type Server
  • func NewServer(e Endpoint, dec DecodeRequestFunc, enc EncodeResponseFunc, ...) *Server
  • func (s Server) ServeHTTP(w http.ResponseWriter, r *http.Request)
• type ServerFinalizerFunc
• type ServerOption
  • func ServerAfter(after ...ServerResponseFunc) ServerOption
  • func ServerBefore(before ...RequestFunc) ServerOption
  • func ServerErrorEncoder(ee ErrorEncoder) ServerOption
  • func ServerErrorHandler(errorHandler ErrorHandler) ServerOption
  • func ServerErrorLogger(logger log.Logger) ServerOption
  • func ServerFinalizer(f ...ServerFinalizerFunc) ServerOption
• type ServerResponseFunc
  • func SetContentType(contentType string) ServerResponseFunc
  • func SetResponseHeader(key, val string) ServerResponseFunc
• type StatusCoder

Constants

const (
	// ContextKeyRequestMethod is populated in the context by
	// PopulateRequestContext. Its value is r.Method.
	ContextKeyRequestMethod contextKey = iota

	// ContextKeyRequestURI is populated in the context by
	// PopulateRequestContext. Its value is r.RequestURI.
	ContextKeyRequestURI

	// ContextKeyRequestPath is populated in the context by
	// PopulateRequestContext. Its value is r.URL.Path.
	ContextKeyRequestPath

	// ContextKeyRequestProto is populated in the context by
	// PopulateRequestContext. Its value is r.Proto.
	ContextKeyRequestProto

	// ContextKeyRequestHost is populated in the context by
	// PopulateRequestContext. Its value is r.Host.
	ContextKeyRequestHost

	// ContextKeyRequestRemoteAddr is populated in the context by
	// PopulateRequestContext. Its value is r.RemoteAddr.
	ContextKeyRequestRemoteAddr

	// ContextKeyRequestXForwardedFor is populated in the context by
	// PopulateRequestContext. Its value is r.Header.Get("X-Forwarded-For").
	ContextKeyRequestXForwardedFor

	// ContextKeyRequestXForwardedProto is populated in the context by
	// PopulateRequestContext. Its value is r.Header.Get("X-Forwarded-Proto").
	ContextKeyRequestXForwardedProto

	// ContextKeyRequestAuthorization is populated in the context by
	// PopulateRequestContext. Its value is r.Header.Get("Authorization").
	ContextKeyRequestAuthorization

	// ContextKeyRequestReferer is populated in the context by
	// PopulateRequestContext. Its value is r.Header.Get("Referer").
	ContextKeyRequestReferer

	// ContextKeyRequestUserAgent is populated in the context by
	// PopulateRequestContext. Its value is r.Header.Get("User-Agent").
	ContextKeyRequestUserAgent

	// ContextKeyRequestXRequestID is populated in the context by
	// PopulateRequestContext. Its value is r.Header.Get("X-Request-Id").
	ContextKeyRequestXRequestID

	// ContextKeyRequestAccept is populated in the context by
	// PopulateRequestContext. Its value is r.Header.Get("Accept").
	ContextKeyRequestAccept

	// ContextKeyResponseHeaders is populated in the context whenever a
	// ServerFinalizerFunc is specified. Its value is of type http.Header, and
	// is captured only once the entire response has been written.
	ContextKeyResponseHeaders

	// ContextKeyResponseSize is populated in the context whenever a
	// ServerFinalizerFunc is specified. Its value is of type int64.
	ContextKeyResponseSize
)

Functions

func DefaultErrorEncoder

func DefaultErrorEncoder(_ context.Context, err error, w http.ResponseWriter)

DefaultErrorEncoder writes the error to the ResponseWriter, by default a content type of text/plain, a body of the plain text of the error, and a status code of 500. If the error implements Headerer, the provided headers will be applied to the response. If the error implements json.Marshaler, and the marshaling succeeds, a content type of application/json and the JSON encoded form of the error will be used. If the error implements StatusCoder, the provided StatusCode will be used instead of 500.

func DefaultHttpErrorEncoder

func DefaultHttpErrorEncoder(_ context.Context, err error, w http.ResponseWriter)

DefaultHttpErrorEncoder

Computes the default http error response. When implementing custom gkBoot.HttpEncoder, ensure to implement your own error encoder handler.

func DefaultHttpResponseEncoder

func DefaultHttpResponseEncoder(ctx context.Context, w http.ResponseWriter, response interface{}) error

DefaultHttpResponseEncoder

Computes the http response encoding, for different formats, you must attach your own gkBoot.HttpEncoder to your gkBoot.Service for each one defined

func EncodeJSONResponse

func EncodeJSONResponse(_ context.Context, w http.ResponseWriter, response interface{}) error

EncodeJSONResponse is a EncodeResponseFunc that serializes the response as a JSON object to the ResponseWriter. Many JSON-over-HTTP services can use it as a sensible default. If the response implements Headerer, the provided headers will be applied to the response. If the response implements StatusCoder, the provided StatusCode will be used instead of 200.

func Nop

func Nop(context.Context, interface{}) (interface{}, error)

Nop is an endpoint that does nothing and returns a nil error. Useful for tests.

func NopRequestDecoder

func NopRequestDecoder(ctx context.Context, r *http.Request) (interface{}, error)

NopRequestDecoder is a DecodeRequestFunc that can be used for requests that do not need to be decoded, and simply returns nil, nil.

func PopulateRequestContext

func PopulateRequestContext(ctx context.Context, r *http.Request) context.Context

PopulateRequestContext is a RequestFunc that populates several values into the context from the HTTP request. Those values may be extracted using the corresponding ContextKey type in this package.

Types

type ClientResponseFunc

type ClientResponseFunc func(context.Context, *http.Response) context.Context

ClientResponseFunc may take information from an HTTP 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 CodedError

type CodedError interface {
	StatusCode() int
}

CodedError

Indicates an error capable of storing a status code. Used with default (en/de)-coders

type DecodeRequestFunc

type DecodeRequestFunc func(context.Context, *http.Request) (request interface{}, err error)

DecodeRequestFunc any decoder that takes on this format, goal is to translate http.Request to API request object

type EncodeResponseFunc

type EncodeResponseFunc func(context.Context, http.ResponseWriter, interface{}) error

EncodeResponseFunc any encoder that takes on this format, goal is to translate API response object to the http.ResponseWriter

type Endpoint

type Endpoint func(ctx context.Context, request interface{}) (response interface{}, err error)

Endpoint is the fundamental building block of servers and clients. It represents a single RPC method.

type ErrorEncoder

type ErrorEncoder func(ctx context.Context, err error, w http.ResponseWriter)

ErrorEncoder is responsible for encoding an error to the ResponseWriter. Users are encouraged to use custom ErrorEncoders to encode HTTP errors to their clients, and will likely want to pass and check for their own error types. See the example shipping/handling service.

type ErrorHandler

type ErrorHandler interface {
	Handle(ctx context.Context, err error)
}

ErrorHandler receives a transport error to be processed for diagnostic purposes. Usually this means logging the error.

type ErrorHandlerFunc

type ErrorHandlerFunc func(ctx context.Context, err error)

The ErrorHandlerFunc type is an adapter to allow the use of ordinary function as ErrorHandler. If f is a function with the appropriate signature, ErrorHandlerFunc(f) is a ErrorHandler that calls f.

func (ErrorHandlerFunc) Handle

func (f ErrorHandlerFunc) Handle(ctx context.Context, err error)

Handle calls f(ctx, err).

type Failer

type Failer interface {
	Failed() error
}

Failer may be implemented by Go kit response types that contain business logic error details. If Failed returns a non-nil error, the Go kit transport layer may interpret this as a business logic error, and may encode it differently than a regular, successful response.

It's not necessary for your response types to implement Failer, but it may help for more sophisticated use cases. The addsvc example shows how Failer should be used by a complete application.

type Headerer

type Headerer interface {
	Headers() http.Header
}

Headerer is checked by DefaultErrorEncoder. If an error value implements Headerer, the provided headers will be applied to the response writer, after the Content-Type is set.

type HttpCoder

type HttpCoder interface {
	StatusCode() int
}

HttpCoder is any response that returns a status code

type LogErrorHandler

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

LogErrorHandler is a transport error handler implementation which logs an error.

func NewLogErrorHandler

func NewLogErrorHandler(logger log.Logger) *LogErrorHandler

func (*LogErrorHandler) Handle

func (h *LogErrorHandler) Handle(ctx context.Context, err error)

type Middleware

type Middleware func(Endpoint) Endpoint

Middleware is a chainable behavior modifier for endpoints.

type RequestFunc

type RequestFunc func(context.Context, *http.Request) context.Context

RequestFunc may take information from an HTTP request and put it into a request context. In Servers, RequestFuncs are executed prior to invoking the endpoint. In Clients, RequestFuncs are executed after creating the request but prior to invoking the HTTP client.

func SetRequestHeader

func SetRequestHeader(key, val string) RequestFunc

SetRequestHeader returns a RequestFunc that sets the given header.

type Server

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

Server wraps an endpoint and implements http.Handler.

func NewServer

func NewServer(
	e Endpoint,
	dec DecodeRequestFunc,
	enc EncodeResponseFunc,
	options ...ServerOption,
) *Server

NewServer constructs a new server, which implements http.Handler and wraps the provided endpoint.

func (Server) ServeHTTP

func (s Server) ServeHTTP(w http.ResponseWriter, r *http.Request)

ServeHTTP implements http.Handler.

type ServerFinalizerFunc

type ServerFinalizerFunc func(ctx context.Context, code int, r *http.Request)

ServerFinalizerFunc can be used to perform work at the end of an HTTP request, after the response has been written to the client. The principal intended use is for request logging. In addition to the response code provided in the function signature, additional response parameters are provided in the context under keys with the ContextKeyResponse prefix.

type ServerOption

type ServerOption func(*Server)

ServerOption sets an optional parameter for servers.

func ServerAfter

func ServerAfter(after ...ServerResponseFunc) ServerOption

ServerAfter functions are executed on the HTTP response writer after the endpoint is invoked, but before anything is written to the client.

func ServerBefore

func ServerBefore(before ...RequestFunc) ServerOption

ServerBefore functions are executed on the HTTP request object before the request is decoded.

func ServerErrorEncoder

func ServerErrorEncoder(ee ErrorEncoder) ServerOption

ServerErrorEncoder is used to encode errors to the http.ResponseWriter whenever they're encountered in the processing of a request. Clients can use this to provide custom error formatting and response codes. By default, errors will be written with the DefaultErrorEncoder.

func ServerErrorHandler

func ServerErrorHandler(errorHandler ErrorHandler) ServerOption

ServerErrorHandler is used to handle non-terminal errors. By default, non-terminal errors are ignored. This is intended as a diagnostic measure. Finer-grained control of error handling, including logging in more detail, should be performed in a custom ServerErrorEncoder or ServerFinalizer, both of which have access to the context.

func ServerErrorLogger

func ServerErrorLogger(logger log.Logger) ServerOption

ServerErrorLogger 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 ServerErrorEncoder or ServerFinalizer, both of which have access to the context. Deprecated: Use ServerErrorHandler instead.

func ServerFinalizer

func ServerFinalizer(f ...ServerFinalizerFunc) ServerOption

ServerFinalizer is executed at the end of every HTTP request. By default, no finalizer is registered.

type ServerResponseFunc

type ServerResponseFunc func(context.Context, http.ResponseWriter) context.Context

ServerResponseFunc may take information from a request context and use it to manipulate a ResponseWriter. ServerResponseFuncs are only executed in servers, after invoking the endpoint but prior to writing a response.

func SetContentType

func SetContentType(contentType string) ServerResponseFunc

SetContentType returns a ServerResponseFunc that sets the Content-Type header to the provided value.

func SetResponseHeader

func SetResponseHeader(key, val string) ServerResponseFunc

SetResponseHeader returns a ServerResponseFunc that sets the given header.

type StatusCoder

type StatusCoder interface {
	StatusCode() int
}

StatusCoder is checked by DefaultErrorEncoder. If an error value implements StatusCoder, the StatusCode will be used when encoding the error. By default, StatusInternalServerError (500) is used.