get_nested.py

Get nested fields in a dictionary based on dotted names

def get_nested_field(message: dict, field: str):
    '''
    Iterates over nested fields to get the final desired value
    e.g signal.rule.name should return the value of name

    Paramters:
        message (dict): A dictionary of values you want to iterate over
        field (str): The field you want to extract from the message in dotted format

    Return:
        value: The extracted value, may be the response from this function calling itself again
    '''

    if isinstance(field, str):
        args = field.split('.')
    else:
        args = field

    if args and message:
        element = args[0]
        if element:
            if isinstance(message, list):
                values = []
                value = [m for m in message if m is not None]
                if any(isinstance(i, list) for i in value):
                    for l in value:
                        if isinstance(l, list):
                            values += [v for v in l if v is not None]
                else:
                    values += [v for v in value if not isinstance(v, list)]
                value = values
                    
            else:
                value = message.get(element)

            if isinstance(value, list):
                if len(value) > 0 and isinstance(value[0], dict):
                    value = [get_nested_field(item, args[1:]) for item in value]
                    
                
            return value if len(args) == 1 else get_nested_field(value, args[1:])