Class ConfigParser

monai/bundle/config_parser.py:237–718

The primary configuration parser. It traverses a structured config (in the form of nested Python dict or list), creates ``ConfigItem``, and assign unique IDs according to the structures. This class provides convenient access to the set of ``ConfigItem`` of the config by ID. A typic

class ConfigParser:
    """
    The primary configuration parser. It traverses a structured config (in the form of nested Python dict or list),
    creates ``ConfigItem``, and assign unique IDs according to the structures.

    This class provides convenient access to the set of ``ConfigItem`` of the config by ID.
    A typical workflow of config parsing is as follows:

        - Initialize ``ConfigParser`` with the ``config`` source.
        - Call ``get_parsed_content()`` to get expected component with `id`.

    .. code-block:: python

        from monai.bundle import ConfigParser

        config = {
            "my_dims": 2,
            "dims_1": "$@my_dims + 1",
            "my_xform": {"_target_": "LoadImage"},
            "my_net": {"_target_": "BasicUNet", "spatial_dims": "@dims_1", "in_channels": 1, "out_channels": 4},
            "trainer": {"_target_": "SupervisedTrainer", "network": "@my_net", "preprocessing": "@my_xform"}
        }
        # in the example $@my_dims + 1 is an expression, which adds 1 to the value of @my_dims
        parser = ConfigParser(config)

        # get/set configuration content, the set method should happen before calling parse()
        print(parser["my_net"]["in_channels"])  # original input channels 1
        parser["my_net"]["in_channels"] = 4  # change input channels to 4
        print(parser["my_net"]["in_channels"])

        # instantiate the network component
        parser.parse(True)
        net = parser.get_parsed_content("my_net", instantiate=True)
        print(net)

        # also support to get the configuration content of parsed `ConfigItem`
        trainer = parser.get_parsed_content("trainer", instantiate=False)
        print(trainer)

    Args:
        config: input config source to parse.
        excludes: when importing modules to instantiate components,
            excluding components from modules specified in ``excludes``.
        globals: pre-import packages as global variables to ``ConfigExpression``,
            so that expressions, for example, ``"$monai.data.list_data_collate"`` can use ``monai`` modules.
            The current supported globals and alias names are
            ``{"monai": "monai", "torch": "torch", "np": "numpy", "numpy": "numpy"}``.
            These are MONAI's minimal dependencies. Additional packages could be included with `globals={"itk": "itk"}`.
            Set it to ``False`` to disable `self.globals` module importing.

    See also:

        - :py:class:`monai.bundle.ConfigItem`
        - :py:class:`monai.bundle.scripts.run`

    """

    suffixes = ("json", "yaml", "yml")