Source code for dclab.rtdc_dataset.feat_anc_plugin.plugin_feature

"""
.. versionadded:: 0.34.0
"""
import hashlib
import importlib
import pathlib
import sys

from ...definitions import feat_logic
from ..feat_anc_core import AncillaryFeature


[docs]class PluginImportError(BaseException): pass
[docs]def import_plugin_feature_script(plugin_path): """Import the user-defined recipe and return the info dictionary Parameters ---------- plugin_path: str or Path pathname to a valid dclab plugin script Returns ------- info: dict Dictionary with the information required to instantiate one (or multiple) :class:`PlugInFeature`. Raises ------ PluginImportError If the plugin can not be found """ path = pathlib.Path(plugin_path) if not path.exists(): raise PluginImportError("The plugin could be not be found at " f"'{plugin_path}'!") try: # insert the plugin directory to sys.path so we can import it sys.path.insert(-1, str(path.parent)) sys.dont_write_bytecode = True plugin = importlib.import_module(path.stem) except BaseException as e: raise PluginImportError( f"The plugin {plugin_path} could not be loaded!") from e finally: # undo our path insertion sys.path.pop(0) sys.dont_write_bytecode = False return plugin.info
[docs]def load_plugin_feature(plugin_path): """Find and load PlugInFeature(s) from a user-defined recipe Parameters ---------- plugin_path: str or Path pathname to a valid dclab plugin Python script Returns ------- plugin_list: list of PlugInFeature list of PlugInFeature instances loaded from `plugin_path` Raises ------ ValueError If the script dictionary "feature names" are not a list See Also -------- import_plugin_feature_script: function that imports the plugin script PlugInFeature: class handling the plugin feature information dclab.rtdc_dataset.feat_temp.register_temporary_feature: alternative method for creating user-defined features """ info = import_plugin_feature_script(plugin_path) if not isinstance(info["feature names"], list): raise ValueError( "'feature names' must be a list of strings.") plugin_list = [] for feature_name in info["feature names"]: plugin_list.append(PlugInFeature(feature_name, info, plugin_path)) return plugin_list
[docs]def remove_all_plugin_features(): """Convenience function for removing all `PlugInFeature` instances See Also -------- remove_plugin_feature: remove a single `PlugInFeature` instance """ for plugin_instance in reversed(PlugInFeature.features): if isinstance(plugin_instance, PlugInFeature): remove_plugin_feature(plugin_instance)
[docs]def remove_plugin_feature(plugin_instance): """Convenience function for removing a `PlugInFeature` instance Parameters ---------- plugin_instance: PlugInFeature The `PlugInFeature` instance to be removed from dclab Raises ------ TypeError If the `plugin_instance` is not a `PlugInFeature` instance """ if isinstance(plugin_instance, PlugInFeature): # This check is necessary for situations where the PlugInFeature fails # between updating the `dclab.dfn` file and initialising the # AncillaryFeature if plugin_instance.feature_name in PlugInFeature.feature_names: PlugInFeature.feature_names.remove(plugin_instance.feature_name) feat_logic.feature_deregister(plugin_instance.feature_name) PlugInFeature.features.remove(plugin_instance) else: raise TypeError(f"Type {type(plugin_instance)} should be an instance " f"of PlugInFeature. '{plugin_instance}' was given.")
[docs]class PlugInFeature(AncillaryFeature): def __init__(self, feature_name, info, plugin_path=None): """A user-defined plugin feature Parameters ---------- feature_name: str name of a feature that matches that defined in `info` info: dict Full plugin recipe (for all features) as given in the `info` dictionary in the plugin file. At least the following keys must be specified: - "method": callable function computing the plugin feature values (takes an :class`dclab.rtdc_dataset.core.RTDCBase` as argument) - "feature names": list of plugin feature names provided by the plugin The following features are optional: - "description": short (one-line) description of the plugin - "long description": long description of the plugin - "feature labels": feature labels used e.g. for plotting - "feature shapes": list of tuples for each feature indicating the shape (this is required only for non-scalar features; for scalar features simply set this to ``None`` or ``(1,)``). - "scalar feature": list of boolean values indicating whether the features are scalar - "config required": configuration keys required to compute the plugin features (see the `req_config` parameter for :class:`.AncillaryFeature`) - "features required": list of feature names required to compute the plugin features (see the `req_features` parameter for :class:`.AncillaryFeature`) - "method check required": additional method that checks whether the features can be computed (see the `req_func` parameter for :class:`.AncillaryFeature`) - "version": version of this plugin (please use semantic verioning) plugin_path: str or Path, optional path which was used to load the `PlugInFeature` with :func:`load_plugin_feature`. Notes ----- `PluginFeature` inherits from :class:`AncillaryFeature <dclab.rtdc_dataset.feat_anc_core.ancillary_feature.AncillaryFeature>`. Please read the advanced section on `PluginFeatures` in the dclab docs. """ if plugin_path is not None: plugin_path = pathlib.Path(plugin_path) #: Plugin feature name self.feature_name = feature_name #: Path to the original plugin file self.plugin_path = plugin_path # perform sanity checks self._sanity_check_original_info(info) # keep this for tests self._original_info = info # populate `info` dictionary with missing values #: Dictionary containing all information relevant for #: this particular plugin feature instance self.plugin_feature_info = self._process_plugin_info(info) # register this plugin feature in definitions # This must be executed before initializing the super class # (AncillaryFeature). If we don't do this, then `remove_plugin_feature` # may end up removing innate features e.g., "deform". feat_logic.feature_register( name=self.feature_name, label=self.plugin_feature_info["feature label"], is_scalar=self.plugin_feature_info["scalar feature"] ) # Instantiate the super class super(PlugInFeature, self).__init__( feature_name=self.plugin_feature_info["feature name"], method=self.plugin_feature_info["method"], req_config=self.plugin_feature_info["config required"], req_features=self.plugin_feature_info["features required"], req_func=self.plugin_feature_info["method check required"], identifier=self.plugin_feature_info["identifier"], ) def _process_plugin_info(self, original_info): """Return dictionary with all relevant info for this instance """ fidx = original_info["feature names"].index(self.feature_name) # determine feature label if ("feature labels" in original_info and original_info["feature labels"][fidx]): label = original_info["feature labels"][fidx] else: label = f"Plugin feature {self.feature_name}" # determine whether we have a scalar feature if "scalar feature" in original_info: is_scalar = original_info["scalar feature"][fidx] else: is_scalar = True # default if is_scalar: event_shape = (1,) else: if "feature shapes" in original_info: event_shape = original_info["feature shapes"][fidx] else: event_shape = None # We assume that the script does not import any other custom # Python scripts. md5hasher = hashlib.md5() if self.plugin_path is not None: md5hasher.update(self.plugin_path.read_bytes()) else: md5hasher.update(original_info["method"].__code__.co_code) md5hasher.update(self.feature_name.encode("utf-8")) md5hasher.update(original_info.get("version", "").encode("utf-8")) for feat in original_info.get("features required", []): md5hasher.update(feat.encode("utf-8")) identifier = md5hasher.hexdigest() feature_info = { "method": original_info["method"], "description": original_info.get( "description", "No description provided"), "long description": original_info.get( "long description", "No long description provided."), "feature name": self.feature_name, "feature label": label, "feature shape": event_shape, "features required": original_info.get("features required", []), "config required": original_info.get("config required", []), "method check required": original_info.get( "method check required", lambda x: True), "scalar feature": is_scalar, # allow comparisons with distutil.version.LooseVersion "version": original_info.get("version", "0.0.0-unknown"), "plugin path": self.plugin_path, "identifier": identifier, } return feature_info def _sanity_check_original_info(self, original_info): """Various checks on the `original_info` attribute dict Raises ------ ValueError If the parameter `original_info` is not a dict. If the `self.feature_name` is not in `original_info["feature names"]`. If the `method` provided in parameter `original_info` is not callable. """ if not isinstance(original_info, dict): raise ValueError( "PlugInFeature parameter for `info` must be a dict, instead " f"a '{type(original_info)}' was given.") if not isinstance(original_info["feature names"], list): raise ValueError("'feature names' must be a list, " f"got '{type(original_info['feature names'])}'") if self.feature_name not in original_info["feature names"]: raise ValueError( f"The feature name '{self.feature_name}' is not defined in " + "the `info` dict of the plugin feature" + (f" at {self.plugin_path}" if self.plugin_path else "") + f". Defined names are '{original_info['feature names']}'.") if not callable(original_info["method"]): raise ValueError( "The `method` you have provided in the parameter `info` is " f"not callable ('{original_info['method']}' is not " "a function).")