src/bindings/python/bt2/bt2/query_executor.py

   1 # The MIT License (MIT)
   2 #
   3 # Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>
   4 #
   5 # Permission is hereby granted, free of charge, to any person obtaining a copy
   6 # of this software and associated documentation files (the "Software"), to deal
   7 # in the Software without restriction, including without limitation the rights
   8 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   9 # copies of the Software, and to permit persons to whom the Software is
  10 # furnished to do so, subject to the following conditions:
  11 #
  12 # The above copyright notice and this permission notice shall be included in
  13 # all copies or substantial portions of the Software.
  14 #
  15 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  21 # THE SOFTWARE.
  22
  23 from bt2 import native_bt, object, utils
  24 import bt2.component
  25 import bt2.logging
  26 import bt2
  27
  28
  29 class QueryExecutor(object._SharedObject):
  30     _get_ref = staticmethod(native_bt.query_executor_get_ref)
  31     _put_ref = staticmethod(native_bt.query_executor_put_ref)
  32
  33     def __init__(self):
  34         ptr = native_bt.query_executor_create()
  35
  36         if ptr is None:
  37             raise bt2.CreationError('cannot create query executor object')
  38
  39         super().__init__(ptr)
  40
  41     def cancel(self):
  42         status = native_bt.query_executor_cancel(self._ptr)
  43         utils._handle_func_status(status, 'cannot cancel query executor object')
  44
  45     @property
  46     def is_canceled(self):
  47         is_canceled = native_bt.query_executor_is_canceled(self._ptr)
  48         assert is_canceled >= 0
  49         return is_canceled > 0
  50
  51     def query(
  52         self,
  53         component_class,
  54         object,
  55         params=None,
  56         logging_level=bt2.logging.LoggingLevel.NONE,
  57     ):
  58         if self.is_canceled:
  59             raise bt2.Canceled
  60
  61         if not isinstance(component_class, bt2.component._GenericComponentClass):
  62             err = False
  63
  64             try:
  65                 if not issubclass(component_class, bt2.component._UserComponent):
  66                     err = True
  67             except TypeError:
  68                 err = True
  69
  70             if err:
  71                 o = component_class
  72                 raise TypeError("'{}' is not a component class object".format(o))
  73
  74         utils._check_str(object)
  75
  76         if params is None:
  77             params_ptr = native_bt.value_null
  78         else:
  79             params = bt2.create_value(params)
  80             params_ptr = params._ptr
  81
  82         utils._check_log_level(logging_level)
  83         cc_ptr = component_class._bt_component_class_ptr()
  84
  85         status, result_ptr = native_bt.query_executor_query(
  86             self._ptr, cc_ptr, object, params_ptr, logging_level
  87         )
  88         utils._handle_func_status(status, 'cannot query component class')
  89         assert result_ptr
  90         return bt2.value._create_from_ptr(result_ptr)