Native FLARE/XGB integration (#2354)

* fed xgb

* support c integration

* implement c server bridge

* add docstring; change bridge to adaptor

* integrate with xgb federated

* remove unused import

* reorganize

* fix format

* added in_process support flag

* add license text

* fix fstring

* change task timeout back to int

* add docstr; removed unused code

nvflare/app_common/xgb/__init__.py

@@ -0,0 +1,18 @@
+# Copyright (c) 2023, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from nvflare.app_common.xgb.fed_controller import XGBFedController
+from nvflare.app_common.xgb.fed_executor import FedXGBHistogramExecutor
+from nvflare.app_common.xgb.mock.mock_controller import MockXGBController
+from nvflare.app_common.xgb.mock.mock_executor import MockXGBExecutor

nvflare/app_common/xgb/adaptors/__init__.py

@@ -0,0 +1,13 @@
+# Copyright (c) 2023, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.