func (s *server) handle(trans transport.Transport, req_ tmsg.Request) {
req := mercury.FromTyphonRequest(req_)
req, rsp := s.applyRequestMiddleware(req)
if rsp == nil {
if ep, ok := s.Endpoint(req.Endpoint()); !ok {
log.Warn(req, "[Mercury:Server] Received request %s for unknown endpoint %s", req.Id(), req.Endpoint())
rsp = ErrorResponse(req, errEndpointNotFound)
} else {
if rsp_, err := ep.Handle(req); err != nil {
rsp = ErrorResponse(req, err)
log.Info(req, "[Mercury:Server] Error from endpoint %s for %v: %v", ep.Name, req, err, map[string]string{
"request_payload": string(req.Payload())})
} else if rsp_ == nil {
rsp = req.Response(nil)
} else {
rsp = rsp_
}
}
}
rsp = s.applyResponseMiddleware(rsp, req)
if rsp != nil {
trans.Respond(req, rsp)
}
}
func (c *client) addCall(cc clientCall) {
select {
case <-c.execC:
log.Warn(cc.req, "[Mercury:Client] Request added after client execution; discarding")
return
default:
}
c.Lock()
defer c.Unlock()
c.calls[cc.uid] = cc
}
// 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 (s *server) start(trans transport.Transport) (*tomb.Tomb, error) {
ctx := context.Background()
s.workerTombM.Lock()
if s.workerTomb != nil {
s.workerTombM.Unlock()
return nil, ErrAlreadyRunning
}
tm := new(tomb.Tomb)
s.workerTomb = tm
s.workerTombM.Unlock()
stop := func() {
trans.StopListening(s.Name())
s.workerTombM.Lock()
s.workerTomb = nil
s.workerTombM.Unlock()
}
var inbound chan tmsg.Request
connect := func() error {
select {
case <-trans.Ready():
inbound = make(chan tmsg.Request, 500)
return trans.Listen(s.Name(), inbound)
case <-time.After(connectTimeout):
log.Warn(ctx, "[Mercury:Server] Timed out after %v waiting for transport readiness", connectTimeout)
return ttrans.ErrTimeout
}
}
// Block here purposefully (deliberately not in the goroutine below, because we want to report a connection error
// to the caller)
if err := connect(); err != nil {
stop()
return nil, err
}
tm.Go(func() error {
defer stop()
for {
select {
case req, ok := <-inbound:
if !ok {
// Received because the channel closed; try to reconnect
log.Warn(ctx, "[Mercury:Server] Inbound channel closed; trying to reconnect…")
if err := connect(); err != nil {
log.Critical(ctx, "[Mercury:Server] Could not reconnect after channel close: %s", err)
return err
}
} else {
go s.handle(trans, req)
}
case <-tm.Dying():
return tomb.ErrDying
}
}
})
return tm, nil
}
