Add PluginEnv to SystemView (#5028)

logical/plugin.proto

@@ -0,0 +1,10 @@
+syntax = "proto3";
+
+option go_package = "github.com/hashicorp/vault/logical";
+
+package logical;
+
+message PluginEnvironment {
+	// VaultVersion is the version of the Vault server
+	string vault_version = 1;
+}

logical/plugin/grpc_system.go

@@ -146,6 +146,15 @@ func (s *gRPCSystemViewClient) EntityInfo(entityID string) (*logical.Entity, err
 	return reply.Entity, nil
 }
 
+func (s *gRPCSystemViewClient) PluginEnv(ctx context.Context) (*logical.PluginEnvironment, error) {
+	reply, err := s.client.PluginEnv(ctx, &pb.Empty{})
+	if err != nil {
+		return nil, err
+	}
+
+	return reply.PluginEnvironment, nil
+}
+
 type gRPCSystemViewServer struct {
 	impl logical.SystemView
 }
@@ -242,3 +251,15 @@ func (s *gRPCSystemViewServer) EntityInfo(ctx context.Context, args *pb.EntityIn
 		Entity: entity,
 	}, nil
 }
+
+func (s *gRPCSystemViewServer) PluginEnv(ctx context.Context, _ *pb.Empty) (*pb.PluginEnvReply, error) {
+	pluginEnv, err := s.impl.PluginEnv(ctx)
+	if err != nil {
+		return &pb.PluginEnvReply{
+			Err: pb.ErrToString(err),
+		}, nil
+	}
+	return &pb.PluginEnvReply{
+		PluginEnvironment: pluginEnv,
+	}, nil
+}

logical/plugin/grpc_system_test.go

@@ -201,3 +201,32 @@ func TestSystem_GRPC_entityInfo(t *testing.T) {
 		t.Fatalf("expected: %v, got: %v", sys.EntityVal, actual)
 	}
 }
+
+func TestSystem_GRPC_pluginEnv(t *testing.T) {
+	sys := logical.TestSystemView()
+	sys.PluginEnvironment = &logical.PluginEnvironment{
+		VaultVersion: "0.10.42",
+	}
+	client, _ := plugin.TestGRPCConn(t, func(s *grpc.Server) {
+		pb.RegisterSystemViewServer(s, &gRPCSystemViewServer{
+			impl: sys,
+		})
+	})
+	defer client.Close()
+
+	testSystemView := newGRPCSystemView(client)
+
+	expected, err := sys.PluginEnv(context.Background())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	actual, err := testSystemView.PluginEnv(context.Background())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !proto.Equal(expected, actual) {
+		t.Fatalf("expected: %v, got: %v", expected, actual)
+	}
+}