veyron2/ipc: 3 of n. 'Invoker and Signature' rationalisation.
- implement the changed ipc.Serve signature
- transition all code to use it and ipc.ServeDispatcher
- get rid of the ugliness around calling Serve multiple
times to publish under multiple names in the mount table
and instead provide AddName/RemoveName methods.
Change-Id: Ic5edd709d28e2670369986a5b0fce4cd22e3cafd
diff --git a/runtimes/google/ipc/server.go b/runtimes/google/ipc/server.go
index 44ae7ab..943a71b 100644
--- a/runtimes/google/ipc/server.go
+++ b/runtimes/google/ipc/server.go
@@ -47,7 +47,11 @@
stoppedChan chan struct{} // closed when the server has been stopped.
ns naming.Namespace
servesMountTable bool
- reservedOpt options.ReservedNameDispatcher
+ // TODO(cnicolaou): remove this when the publisher tracks published names
+ // and can return an appropriate error for RemoveName on a name that
+ // wasn't 'Added' for this server.
+ names map[string]struct{}
+ reservedOpt options.ReservedNameDispatcher
// TODO(cnicolaou): add roaming stats to ipcStats
stats *ipcStats // stats for this server.
}
@@ -533,51 +537,66 @@
}
}
-func (s *server) Serve(name string, obj interface{}) error {
+func (s *server) Serve(name string, obj interface{}, authorizer security.Authorizer) error {
if obj == nil {
- // nil is an allowed value for obj.
- return s.ServeDispatcher(name, ipc.Dispatcher(nil))
+ // The ReflectInvoker inside the LeafDispatcher will panic
+ // if called for a nil value.
+ return fmt.Errorf("A nil object is not allowed")
}
- // TRANSITION: this will be disallowed when the transition is complete.
- if disp, ok := obj.(ipc.Dispatcher); ok {
- return s.ServeDispatcher(name, disp)
- }
- // TRANSITION: We may fail the dispatcher type test, but still be a
- // dispatcher becase our Lookup method returns ipc.Invoker and not a
- // raw object. This code here will detect that case and panic as an aid
- // to catching these cases early.
- typ := reflect.TypeOf(obj)
- if lookup, found := typ.MethodByName("Lookup"); found {
- if lookup.Type.NumIn() == 3 && lookup.Type.NumOut() == 3 {
- inv := lookup.Type.Out(0)
- if inv.Name() == "Invoker" {
- panic(fmt.Sprintf("%q has a Lookup that returns an Invoker", lookup.Name))
- }
- }
- }
- // TRANSITION: this will go away in the transition.
- panic("should never get here")
+ return s.ServeDispatcher(name, ipc.LeafDispatcher(obj, authorizer))
}
func (s *server) ServeDispatcher(name string, disp ipc.Dispatcher) error {
- defer vlog.LogCall()()
s.Lock()
defer s.Unlock()
if s.stopped {
return errServerStopped
}
- if s.disp != nil && disp != nil && s.disp != disp {
- return fmt.Errorf("attempt to change dispatcher")
+ if disp == nil {
+ return fmt.Errorf("A nil dispacther is not allowed")
}
- if disp != nil {
- s.disp = disp
+ if s.disp != nil {
+ return fmt.Errorf("Serve or ServeDispatcher has already been called")
}
+ s.disp = disp
+ s.names = make(map[string]struct{})
if len(name) > 0 {
s.publisher.AddName(name)
+ s.names[name] = struct{}{}
}
return nil
}
+func (s *server) AddName(name string) error {
+ s.Lock()
+ defer s.Unlock()
+ if s.stopped {
+ return errServerStopped
+ }
+ if len(name) == 0 {
+ return fmt.Errorf("empty name")
+ }
+ s.publisher.AddName(name)
+ // TODO(cnicolaou): remove this map when the publisher's RemoveName
+ // method returns an error.
+ s.names[name] = struct{}{}
+ return nil
+}
+
+func (s *server) RemoveName(name string) error {
+ s.Lock()
+ defer s.Unlock()
+ if s.stopped {
+ return errServerStopped
+ }
+ if _, present := s.names[name]; !present {
+ return fmt.Errorf("%q has not been previously used for this server", name)
+ }
+ s.publisher.RemoveName(name)
+ delete(s.names, name)
+ return nil
+}
+
func (s *server) Stop() error {
defer vlog.LogCall()()
s.Lock()
