def __init__()

in azure/functions/extension/func_extension_base.py [0:0]

• 22 lines of code
• 6 McCabe index (conditional complexity)

    def __init__(self, file_path: str):
        """Constructor for extension. This needs to be implemented and ensure
        super().__init__(file_path) is called.

        The initializer serializes the extension to a tree. This speeds
        up the worker lookup and reduce the overhead on each invocation.
        _func_exts[<trigger_name>].<hook_name>.(ext_name, ext_impl)
        (e.g. _func_exts['HttpTrigger'].pre_invocation.ext_impl)

        Parameters
        ----------
        file_path: str
            The name of trigger the extension attaches to (e.g. __file__).
        """
        script_root = os.getenv('AzureWebJobsScriptRoot')
        if script_root is None:
            raise FunctionExtensionException(
                'AzureWebJobsScriptRoot environment variable is not defined. '
                'Please ensure the extension is running in Azure Functions.'
            )

        # Split will always return ('') in if no folder exist in the path
        relpath_to_project_root = os.path.relpath(
            os.path.normpath(file_path),
            os.path.normpath(script_root)
        )

        trigger_name = (relpath_to_project_root.split(os.sep) or [''])[0]
        if not trigger_name or trigger_name.startswith(('.', '..')):
            raise FunctionExtensionException(
                'Failed to parse trigger name from filename. '
                'Function extension should bind to a trigger script, '
                'not share folder. Please ensure extension is create inside a'
                'trigger while __file__ is passed into the argument. '
                'The trigger name is resolved from os.path.relpath(file_path,'
                'project_root).'
            )

        # This is used in ExtensionMeta._register_function_extension
        self._trigger_name = trigger_name