--- /dev/null
+# The MIT License (MIT)
+#
+# Copyright (c) 2018 Francis Deslauriers <francis.deslauriers@efficios.com>
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+import collections
+from bt2 import native_bt, object
+
+
+class Scope:
+ PACKET_CONTEXT = native_bt.SCOPE_PACKET_CONTEXT
+ EVENT_COMMON_CONTEXT = native_bt.SCOPE_EVENT_COMMON_CONTEXT
+ EVENT_SPECIFIC_CONTEXT = native_bt.SCOPE_EVENT_SPECIFIC_CONTEXT
+ EVENT_PAYLOAD = native_bt.SCOPE_EVENT_PAYLOAD
+
+
+class _FieldPathItem:
+ pass
+
+
+class _IndexFieldPathItem(_FieldPathItem):
+ def __init__(self, index):
+ self._index = index
+
+ @property
+ def index(self):
+ return self._index
+
+
+class _CurrentArrayElementFieldPathItem(_FieldPathItem):
+ pass
+
+
+class _FieldPath(object._SharedObject, collections.abc.Iterable):
+ _get_ref = staticmethod(native_bt.field_path_get_ref)
+ _put_ref = staticmethod(native_bt.field_path_put_ref)
+
+ @property
+ def root_scope(self):
+ scope = native_bt.field_path_get_root_scope(self._ptr)
+ return _SCOPE_TO_OBJ[scope]
+
+ def __len__(self):
+ return native_bt.field_path_get_item_count(self._ptr)
+
+ def __iter__(self):
+ for idx in range(len(self)):
+ item_ptr = native_bt.field_path_borrow_item_by_index_const(self._ptr, idx)
+ assert item_ptr is not None
+ item_type = native_bt.field_path_item_get_type(item_ptr)
+ if item_type == native_bt.FIELD_PATH_ITEM_TYPE_INDEX:
+ idx = native_bt.field_path_item_index_get_index(item_ptr)
+ yield _IndexFieldPathItem(idx)
+ elif item_type == native_bt.FIELD_PATH_ITEM_TYPE_CURRENT_ARRAY_ELEMENT:
+ yield _CurrentArrayElementFieldPathItem()
+ else:
+ assert False
+
+
+_SCOPE_TO_OBJ = {
+ native_bt.SCOPE_PACKET_CONTEXT: Scope.PACKET_CONTEXT,
+ native_bt.SCOPE_EVENT_COMMON_CONTEXT: Scope.EVENT_COMMON_CONTEXT,
+ native_bt.SCOPE_EVENT_SPECIFIC_CONTEXT: Scope.EVENT_SPECIFIC_CONTEXT,
+ native_bt.SCOPE_EVENT_PAYLOAD: Scope.EVENT_PAYLOAD
+}