metropolis: stub out log service

The server side and client-side implementations are not quite ready yet,
but we're commiting this early so that we can start implementing more
node-local management RPCs.

Change-Id: I81b615b0f77dc7750cc738d60ee4923c3182721b
Reviewed-on: https://review.monogon.dev/c/monogon/+/1429
Tested-by: Jenkins CI
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
diff --git a/metropolis/node/core/mgmt/BUILD.bazel b/metropolis/node/core/mgmt/BUILD.bazel
index 41a25d2..349f13e 100644
--- a/metropolis/node/core/mgmt/BUILD.bazel
+++ b/metropolis/node/core/mgmt/BUILD.bazel
@@ -2,7 +2,10 @@
 
 go_library(
     name = "mgmt",
-    srcs = ["mgmt.go"],
+    srcs = [
+        "mgmt.go",
+        "svc_logs.go",
+    ],
     importpath = "source.monogon.dev/metropolis/node/core/mgmt",
     visibility = ["//visibility:public"],
     deps = [
@@ -12,5 +15,7 @@
         "//metropolis/pkg/supervisor",
         "//metropolis/proto/api",
         "@org_golang_google_grpc//:go_default_library",
+        "@org_golang_google_grpc//codes",
+        "@org_golang_google_grpc//status",
     ],
 )
diff --git a/metropolis/node/core/mgmt/svc_logs.go b/metropolis/node/core/mgmt/svc_logs.go
new file mode 100644
index 0000000..6e05ce9
--- /dev/null
+++ b/metropolis/node/core/mgmt/svc_logs.go
@@ -0,0 +1,12 @@
+package mgmt
+
+import (
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+
+	"source.monogon.dev/metropolis/proto/api"
+)
+
+func (s *Service) Logs(_ *api.GetLogsRequest, _ api.NodeManagement_LogsServer) error {
+	return status.Error(codes.Unimplemented, "unimplemented")
+}