python: remove internal `import bt2` imports

[babeltrace.git] / src / bindings / python / bt2 / bt2 / graph.py

# SPDX-License-Identifier: MIT
#
# Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>

from bt2 import native_bt
from bt2 import object as bt2_object
from bt2 import utils as bt2_utils
from bt2 import interrupter as bt2_interrupter
from bt2 import connection as bt2_connection
from bt2 import component as bt2_component
import functools
from bt2 import port as bt2_port
from bt2 import logging as bt2_logging
from bt2 import mip as bt2_mip
from bt2 import error as bt2_error
from bt2 import value as bt2_value


def _graph_port_added_listener_from_native(
    user_listener, component_ptr, component_type, port_ptr, port_type
):
    component = bt2_component._create_component_from_const_ptr_and_get_ref(
        component_ptr, component_type
    )
    port = bt2_port._create_from_const_ptr_and_get_ref(port_ptr, port_type)
    user_listener(component, port)


class Graph(bt2_object._SharedObject):
    @staticmethod
    def _get_ref(ptr):
        native_bt.graph_get_ref(ptr)

    @staticmethod
    def _put_ref(ptr):
        native_bt.graph_put_ref(ptr)

    def __init__(self, mip_version=0):
        bt2_utils._check_uint64(mip_version)

        if mip_version > bt2_mip.get_maximal_mip_version():
            raise ValueError("unknown MIP version {}".format(mip_version))

        ptr = native_bt.graph_create(mip_version)

        if ptr is None:
            raise bt2_error._MemoryError("cannot create graph object")

        super().__init__(ptr)

        # list of listener partials to keep a reference as long as
        # this graph exists
        self._listener_partials = []

    def add_component(
        self,
        component_class,
        name,
        params=None,
        obj=None,
        logging_level=bt2_logging.LoggingLevel.NONE,
    ):
        if isinstance(component_class, bt2_component._SourceComponentClassConst):
            cc_ptr = component_class._ptr
            add_fn = native_bt.bt2_graph_add_source_component
            cc_type = native_bt.COMPONENT_CLASS_TYPE_SOURCE
        elif isinstance(component_class, bt2_component._FilterComponentClassConst):
            cc_ptr = component_class._ptr
            add_fn = native_bt.bt2_graph_add_filter_component
            cc_type = native_bt.COMPONENT_CLASS_TYPE_FILTER
        elif isinstance(component_class, bt2_component._SinkComponentClassConst):
            cc_ptr = component_class._ptr
            add_fn = native_bt.bt2_graph_add_sink_component
            cc_type = native_bt.COMPONENT_CLASS_TYPE_SINK
        elif issubclass(component_class, bt2_component._UserSourceComponent):
            cc_ptr = component_class._bt_cc_ptr
            add_fn = native_bt.bt2_graph_add_source_component
            cc_type = native_bt.COMPONENT_CLASS_TYPE_SOURCE
        elif issubclass(component_class, bt2_component._UserSinkComponent):
            cc_ptr = component_class._bt_cc_ptr
            add_fn = native_bt.bt2_graph_add_sink_component
            cc_type = native_bt.COMPONENT_CLASS_TYPE_SINK
        elif issubclass(component_class, bt2_component._UserFilterComponent):
            cc_ptr = component_class._bt_cc_ptr
            add_fn = native_bt.bt2_graph_add_filter_component
            cc_type = native_bt.COMPONENT_CLASS_TYPE_FILTER
        else:
            raise TypeError(
                "'{}' is not a component class".format(
                    component_class.__class__.__name__
                )
            )

        bt2_utils._check_str(name)
        bt2_utils._check_log_level(logging_level)
        base_cc_ptr = component_class._bt_component_class_ptr()

        if obj is not None and not native_bt.bt2_is_python_component_class(base_cc_ptr):
            raise ValueError("cannot pass a Python object to a non-Python component")

        if params is not None and not isinstance(params, (dict, bt2_value.MapValue)):
            raise TypeError("'params' parameter is not a 'dict' or a 'bt2.MapValue'.")

        params = bt2_value.create_value(params)

        params_ptr = params._ptr if params is not None else None

        status, comp_ptr = add_fn(
            self._ptr, cc_ptr, name, params_ptr, obj, logging_level
        )
        bt2_utils._handle_func_status(status, "cannot add component to graph")
        assert comp_ptr
        return bt2_component._create_component_from_const_ptr_and_get_ref(
            comp_ptr, cc_type
        )

    def connect_ports(self, upstream_port, downstream_port):
        bt2_utils._check_type(upstream_port, bt2_port._OutputPortConst)
        bt2_utils._check_type(downstream_port, bt2_port._InputPortConst)
        status, conn_ptr = native_bt.graph_connect_ports(
            self._ptr, upstream_port._ptr, downstream_port._ptr
        )
        bt2_utils._handle_func_status(
            status, "cannot connect component ports within graph"
        )
        assert conn_ptr
        return bt2_connection._ConnectionConst._create_from_ptr_and_get_ref(conn_ptr)

    def add_port_added_listener(self, listener):
        if not callable(listener):
            raise TypeError("'listener' parameter is not callable")

        fn = native_bt.bt2_graph_add_port_added_listener
        listener_from_native = functools.partial(
            _graph_port_added_listener_from_native, listener
        )

        listener_ids = fn(self._ptr, listener_from_native)
        if listener_ids is None:
            raise bt2_error._Error("cannot add listener to graph object")

        # keep the partial's reference
        self._listener_partials.append(listener_from_native)

    def run_once(self):
        status = native_bt.graph_run_once(self._ptr)
        bt2_utils._handle_func_status(status, "graph object could not run once")

    def run(self):
        status = native_bt.graph_run(self._ptr)
        bt2_utils._handle_func_status(status, "graph object stopped running")

    def add_interrupter(self, interrupter):
        bt2_utils._check_type(interrupter, bt2_interrupter.Interrupter)
        native_bt.graph_add_interrupter(self._ptr, interrupter._ptr)

    @property
    def default_interrupter(self):
        ptr = native_bt.graph_borrow_default_interrupter(self._ptr)
        return bt2_interrupter.Interrupter._create_from_ptr_and_get_ref(ptr)