src/backend/base/langflow/custom/attributes.py

from collections.abc import Callable

import emoji
from loguru import logger


def validate_icon(value: str):
    # we are going to use the emoji library to validate the emoji
    # emojis can be defined using the :emoji_name: syntax

    if not value.startswith(":") and not value.endswith(":"):
        return value
    if not value.startswith(":") or not value.endswith(":"):
        # emoji should have both starting and ending colons
        # so if one of them is missing, we will raise
        msg = f"Invalid emoji. {value} is not a valid emoji."
        raise ValueError(msg)

    emoji_value = emoji.emojize(value, variant="emoji_type")
    if value == emoji_value:
        logger.warning(f"Invalid emoji. {value} is not a valid emoji.")
        return value
    return emoji_value


def getattr_return_str(value):
    return str(value) if value else ""


def getattr_return_bool(value):
    if isinstance(value, bool):
        return value
    return None


def getattr_return_list_of_str(value):
    if isinstance(value, list):
        return [str(val) for val in value]
    return []


def getattr_return_list_of_object(value):
    if isinstance(value, list):
        return value
    return []


def getattr_return_list_of_values_from_dict(value):
    if isinstance(value, dict):
        return list(value.values())
    return []


def getattr_return_dict(value):
    if isinstance(value, dict):
        return value
    return {}


ATTR_FUNC_MAPPING: dict[str, Callable] = {
    "display_name": getattr_return_str,
    "description": getattr_return_str,
    "beta": getattr_return_bool,
    "legacy": getattr_return_bool,
    "documentation": getattr_return_str,
    "icon": validate_icon,
    "frozen": getattr_return_bool,
    "is_input": getattr_return_bool,
    "is_output": getattr_return_bool,
    "conditional_paths": getattr_return_list_of_str,
    "_outputs_map": getattr_return_list_of_values_from_dict,
    "_inputs": getattr_return_list_of_values_from_dict,
    "outputs": getattr_return_list_of_object,
    "inputs": getattr_return_list_of_object,
    "metadata": getattr_return_dict,
    "tool_mode": getattr_return_bool,
}