func handler(req mercury.Request) (mercury.Response, error) {
request := req.Body().(*hello.Request)
rsp := req.Response(&hello.Response{
Msg: "Hey " + request.Name,
})
return rsp, nil
}
// Handle takes an inbound Request, unmarshals it, dispatches it to the handler, and serialises the result as a
// Response. Note that the response may be nil.
func (e Endpoint) Handle(req mercury.Request) (rsp mercury.Response, err error) {
// Unmarshal the request body (unless there already is one)
if req.Body() == nil && e.Request != nil {
if um := e.unmarshaler(req); um != nil {
if werr := terrors.Wrap(um.UnmarshalPayload(req), nil); werr != nil {
log.Warnf("[Mercury:Server] Cannot unmarshal request payload: %v", werr)
terr := werr.(*terrors.Error)
terr.Code = terrors.ErrBadRequest
rsp, err = nil, terr
return
}
}
}
defer func() {
if v := recover(); v != nil {
traceVerbose := make([]byte, 1024)
runtime.Stack(traceVerbose, true)
log.Criticalf("[Mercury:Server] Recovered from handler panic for request %s:\n%v\n%s", req.Id(), v,
string(traceVerbose))
rsp, err = nil, terrors.InternalService("panic", fmt.Sprintf("Panic in handler %s:\n%s", req.Endpoint(),
string(traceVerbose)), nil)
}
}()
rsp, err = e.Handler(req)
return
}
func (e Endpoint) unmarshaler(req mercury.Request) tmsg.Unmarshaler {
result := marshaling.Unmarshaler(req.Headers()[marshaling.ContentTypeHeader], e.Request)
if result == nil { // Default to json
result = marshaling.Unmarshaler(marshaling.JSONContentType, e.Request)
}
return result
}
func (m requestTreeMiddleware) ProcessClientRequest(req mercury.Request) mercury.Request {
if req.Headers()[parentIdHeader] == "" { // Don't overwrite an exiting header
if parentId, ok := req.Context().Value(reqIdCtxKey).(string); ok && parentId != "" {
req.SetHeader(parentIdHeader, parentId)
}
}
// Pass through the current service and endpoint as the origin of this request
req.SetHeader(originServiceHeader, CurrentServiceFor(req))
req.SetHeader(originEndpointHeader, CurrentEndpointFor(req))
return req
}
// ErrorResponse constructs a response for the given request, with the given error as its contents. Mercury clients
// know how to unmarshal these errors.
func ErrorResponse(req mercury.Request, err error) mercury.Response {
rsp := req.Response(nil)
var terr *terrors.Error
if err != nil {
terr = terrors.Wrap(err, nil).(*terrors.Error)
}
rsp.SetBody(terrors.Marshal(terr))
if err := tmsg.ProtoMarshaler().MarshalBody(rsp); err != nil {
log.Errorf("[Mercury:Server] Failed to marshal error response: %v", err)
return nil // Not much we can do here
}
rsp.SetIsError(true)
return rsp
}
// Handle takes an inbound Request, unmarshals it, dispatches it to the handler, and serialises the result as a
// Response. Note that the response may be nil.
func (e Endpoint) Handle(req mercury.Request) (mercury.Response, error) {
// Unmarshal the request body (unless there already is one)
if req.Body() == nil && e.Request != nil {
if um := e.unmarshaler(req); um != nil {
if werr := terrors.Wrap(um.UnmarshalPayload(req), nil); werr != nil {
log.Warn(req, "[Mercury:Server] Cannot unmarshal request payload: %v", werr)
terr := werr.(*terrors.Error)
terr.Code = terrors.ErrBadRequest
return nil, terr
}
}
}
return e.Handler(req)
}
func (m *testMw) ProcessClientRequest(req mercury.Request) mercury.Request {
req.SetHeader("X-Foo", "X-Bar")
return req
}
func old2NewRequest(oldReq mercury.Request) typhon.Request {
ep := oldReq.Endpoint()
if !strings.HasPrefix(ep, "/") {
ep = "/" + ep
}
v := typhon.Request{
Context: oldReq.Context(),
Request: http.Request{
Method: "POST",
URL: &url.URL{
Scheme: "http",
Host: oldReq.Service(),
Path: ep},
Proto: "HTTP/1.1",
ProtoMajor: 1,
ProtoMinor: 1,
Header: toHeader(oldReq.Headers()),
Host: oldReq.Service(),
Body: ioutil.NopCloser(bytes.NewReader(oldReq.Payload())),
ContentLength: int64(len(oldReq.Payload()))}}
v.Header.Set(legacyIdHeader, oldReq.Id())
return v
}
func (e Endpoint) unmarshaler(req mercury.Request) tmsg.Unmarshaler {
return marshaling.Unmarshaler(req.Headers()[marshaling.ContentTypeHeader], e.Request)
}
func (m requestTreeMiddleware) ProcessServerRequest(req mercury.Request) (mercury.Request, mercury.Response) {
req.SetContext(context.WithValue(req.Context(), reqIdCtxKey, req.Id()))
if v := req.Headers()[parentIdHeader]; v != "" {
req.SetContext(context.WithValue(req.Context(), parentIdCtxKey, v))
}
// Set the current service and endpoint into the context
req.SetContext(context.WithValue(req.Context(), currentServiceHeader, req.Service()))
req.SetContext(context.WithValue(req.Context(), currentEndpointHeader, req.Endpoint()))
// Set the originator into the context
req.SetContext(context.WithValue(req.Context(), originServiceHeader, req.Headers()[originServiceHeader]))
req.SetContext(context.WithValue(req.Context(), originEndpointHeader, req.Headers()[originEndpointHeader]))
return req, nil
}
