Add basic application framework and example application to show interaction between events an NBI

Depends on:

• !340 (merged)
• !344 (merged)
• !349 (merged)
• !342 (merged)

controller/northbound/server/nbi.go

@@ -4,6 +4,9 @@ import (
 	"code.fbi.h-da.de/danet/gosdn/controller/interfaces/networkdomain"
 	"code.fbi.h-da.de/danet/gosdn/controller/interfaces/rbac"
 	"code.fbi.h-da.de/danet/gosdn/controller/metrics"
+	"code.fbi.h-da.de/danet/gosdn/controller/topology"
+	"code.fbi.h-da.de/danet/gosdn/controller/topology/nodes"
+	"code.fbi.h-da.de/danet/gosdn/controller/topology/ports"
 	"github.com/prometheus/client_golang/prometheus"
 	log "github.com/sirupsen/logrus"
 	"google.golang.org/grpc/codes"
@@ -13,32 +16,48 @@ import (
 var pndc networkdomain.PndStore
 var userService rbac.UserService
 var roleService rbac.RoleService
+var topologyService topology.Service
+var nodeService nodes.Service
+var portService ports.Service
 
 // NorthboundInterface is the representation of the
 // gRPC services used provided.
 type NorthboundInterface struct {
-	Pnd  *pndServer
-	Core *core
-	Csbi *csbi
-	Sbi  *sbiServer
-	Auth *Auth
-	User *User
-	Role *Role
+	Pnd      *pndServer
+	Core     *core
+	Csbi     *csbi
+	Sbi      *sbiServer
+	Auth     *Auth
+	User     *User
+	Role     *Role
+	Topology *Topology
 }
 
 // NewNBI receives a PndStore and returns a new gRPC *NorthboundInterface
-func NewNBI(pnds networkdomain.PndStore, users rbac.UserService, roles rbac.RoleService) *NorthboundInterface {
+func NewNBI(
+	pnds networkdomain.PndStore,
+	users rbac.UserService,
+	roles rbac.RoleService,
+	topology topology.Service,
+	node nodes.Service,
+	port ports.Service,
+) *NorthboundInterface {
 	pndc = pnds
 	userService = users
 	roleService = roles
+	topologyService = topology
+	nodeService = node
+	portService = port
+
 	return &NorthboundInterface{
-		Pnd:  &pndServer{},
-		Core: &core{},
-		Csbi: &csbi{},
-		Sbi:  &sbiServer{},
-		Auth: &Auth{},
-		User: &User{},
-		Role: &Role{},
+		Pnd:      &pndServer{},
+		Core:     &core{},
+		Csbi:     &csbi{},
+		Sbi:      &sbiServer{},
+		Auth:     &Auth{},
+		User:     &User{},
+		Role:     &Role{},
+		Topology: &Topology{},
 	}
 }