Source code for flask_breadcrumbs

# -*- coding: utf-8 -*-
# This file is part of Flask-Breadcrumbs
# Copyright (C) 2013, 2014, 2015, 2016 CERN.
# Flask-Breadcrumbs is free software; you can redistribute it and/or
# modify it under the terms of the Revised BSD License; see LICENSE
# file for more details.

"""Provide support for generating site breadcrumb navigation.

Depends on `flask_menu` extension.

from flask import Blueprint, current_app, request
# pylint: disable=F0401,E0611
from flask_menu import Menu, register_menu, current_menu
# pylint: enable=F0401,E0611
from werkzeug.local import LocalProxy

from .version import __version__

[docs]def default_breadcrumb_root(app, path): """Register default breadcrumb path for all endpoints in this blueprint. :param app: The :class:`~flask.Flask` or :class:`flask.Blueprint` object. :type app: :class:`flask.Flask` or :class:`flask.Blueprint` :param path: Path in the menu hierarchy. It should start with '.' to be relative to breadcrumbs root. """ if path.startswith('.'): # Path relative to breadcrumb root bl_path = LocalProxy(lambda: ( breadcrumb_root_path + path).strip('.')) else: bl_path = path app.__breadcrumb__ = bl_path
[docs]def register_breadcrumb(app, path, text, order=0, endpoint_arguments_constructor=None, dynamic_list_constructor=None): """Decorate endpoints that should be displayed as a breadcrumb. :param app: Application or Blueprint which owns the function. :param path: Path to this item in menu hierarchy ('breadcrumbs.' is automatically added). :param text: Text displayed as link. :param order: Index of item among other items in the same menu. :param endpoint_arguments_constructor: Function returning dict of arguments passed to url_for when creating the link. :param dynamic_list_constructor: Function returning a list of breadcrumbs to be displayed by this item. Every object should have 'text' and 'url' properties/dict elements. """ # Resolve blueprint-relative paths if path.startswith('.'): def _evaluate_path(): """Lazy path evaluation.""" bl_path = Breadcrumbs.get_path(app) return (bl_path + path).strip('.') func_path = LocalProxy(_evaluate_path) else: func_path = path # Get standard menu decorator menu_decorator = register_menu( app, func_path, text, order, endpoint_arguments_constructor=endpoint_arguments_constructor, dynamic_list_constructor=dynamic_list_constructor) def breadcrumb_decorator(func): """Applie standard menu decorator and assign breadcrumb.""" func.__breadcrumb__ = func_path return menu_decorator(func) return breadcrumb_decorator
def _lookup_current_function(): """Return current view function for request endpoint.""" return current_app.view_functions.get(request.endpoint) def _lookup_current_blueprint(): """Return current :class:`~flask.Blueprint` instance. Alternatively return :class:`~flask.Flask` application object when no blueprint is activated during request. """ return current_app.blueprints.get( request.blueprint, current_app._get_current_object()) # pylint: disable=W0212 def _lookup_breadcrumb_root_path(): """Backend function for breadcrumb_root_path proxy.""" return current_app.config.get('BREADCRUMBS_ROOT') # Proxies # pylint: disable-msg=C0103 #: A proxy for the current function. current_function = LocalProxy(_lookup_current_function) #: A proxy for the current blueprint or application object. current_blueprint = LocalProxy(_lookup_current_blueprint) #: A proxy for breadcrumbs root element path. breadcrumb_root_path = LocalProxy(_lookup_breadcrumb_root_path) #: A proxy for detecting current breadcrumb path. current_path = LocalProxy(Breadcrumbs.current_path) #: A proxy for current breadcrumbs list. current_breadcrumbs = LocalProxy(Breadcrumbs.breadcrumbs) # pylint: enable-msg=C0103