ResponseWriter has unexported functions and con not be implemented outside about go-coap HOT 4 CLOSED

type CoapHandler func(w ResponseWriter, r *coap.Request)

func coapHandlerFunc(h CoapHandler) coap.HandlerFunc {
	return func(w coap.ResponseWriter, r *coap.Request) {
		h(w, r)
	}
}

var mux = coap.DefaultServeMux

func InitCoapEndpoints() {
	mux.HandleFunc("/up", coapHandlerFunc(coapUplinkHandler))
}

func coapUplinkHandler(w ResponseWriter, r *coap.Request) {
// ...
}

type ResponseWriter interface {
	Write(p []byte) (n int, err error)
	// WriteContext response with payload.
	// If p is nil it writes response without payload.
	// If p is non-nil then SetContentFormat must be called before Write otherwise Write fails.
	WriteWithContext(ctx context.Context, p []byte) (n int, err error)
	// SetCode for response that is send via Write call.
	//
	// If SetCode is not called explicitly, the first call to Write
	// will trigger an implicit SetCode(Content/Changed/Deleted/Created - depends on request).
	// Thus explicit calls to SetCode are mainly used to send error codes.
	SetCode(code coap.COAPCode)
	// SetContentFormat of payload for response that is send via Write call.
	//
	// If SetContentFormat is not called and Write is called with non-nil argumet
	// If SetContentFormat is set but Write is called with nil argument it fails
	SetContentFormat(contentFormat coap.MediaType)

	//NewResponse create response with code and token, messageid against request
	NewResponse(code coap.COAPCode) coap.Message

	WriteMsg(msg coap.Message) error
	//WriteContextMsg to client.
	//If Option ContentFormat is set and Payload is not set then call will failed.
	//If Option ContentFormat is not set and Payload is set then call will failed.
	WriteMsgWithContext(ctx context.Context, msg coap.Message) error
}

var _ ResponseWriter = ResponseRecorder{}

// ResponseRecorder is an implementation of http.ResponseWriter that
// records its mutations for later inspection in tests.
type ResponseRecorder struct {
	Msg coap.Message
}

// NewRecorder returns an initialized ResponseRecorder.
func NewRecorder() *ResponseRecorder {
	return &ResponseRecorder{
		Msg: coap.NewDgramMessage(coap.MessageParams{}),
	}
}

func (rw ResponseRecorder) Write(buf []byte) (n int, err error) {
	return rw.WriteWithContext(context.Background(), buf)

}

func (rw ResponseRecorder) WriteWithContext(ctx context.Context, buf []byte) (n int, err error) {
	rw.Msg.SetPayload(buf)
	return len(buf), nil
}

func (rw ResponseRecorder) SetCode(code coap.COAPCode) {
	rw.Msg.SetCode(code)
}

func (rw ResponseRecorder) SetContentFormat(contentFormat coap.MediaType) {
	rw.Msg.AddOption(coap.ContentFormat, contentFormat)
}

func (rw ResponseRecorder) NewResponse(code coap.COAPCode) coap.Message {
	panic("implement me")
}

func (rw ResponseRecorder) WriteMsg(msg coap.Message) error {
	rw.Msg = msg
	return nil
}

func (rw ResponseRecorder) WriteMsgWithContext(ctx context.Context, msg coap.Message) error {
	rw.Msg = msg
	return nil
}

func NewRequest(code coap.COAPCode, coapType coap.COAPType, payload []byte) *coap.Request {
	// TODO: Token, MessageId and Sequence???
	r := &coap.Request{
		Msg: coap.NewDgramMessage(coap.MessageParams{
			Code:    code,
			Type:    coapType,
			Payload: payload,
		}),
		Client:   nil,
		Ctx:      nil,
		Sequence: 0,
	}
	return r
}

	rw := coaptest.NewRecorder()

	uplink := UplinkPayload{
		Data:           "here is my payload",
		Identification: env.Dev.Addr,
		Number:         123,
	}
	uplinkCbor, err := cbor.Marshal(uplink)
	assert.NoError(t, err)

	r := coaptest.NewRequest(coap.POST, coap.NonConfirmable, uplinkCbor)
	coapUplinkHandler(rw, r)

	assert.Equal(t, coap.Created, rw.Msg.Code())