Source code for pyramid.view

import venusian

from zope.interface import providedBy
from zope.deprecation import deprecated

from pyramid.interfaces import (
    IRoutesMapper,
    IView,
    IViewClassifier,
    )

from pyramid.compat import (
    map_,
    decode_path_info,
    )

from pyramid.httpexceptions import (
    HTTPFound,
    default_exceptionresponse_view,
    )

from pyramid.path import caller_package
from pyramid.static import static_view
from pyramid.threadlocal import get_current_registry

_marker = object()

[docs]class static(static_view): """ Backwards compatibility alias for :class:`pyramid.static.static_view`; it overrides that class' constructor to pass ``use_subpath=True`` by default. This class is deprecated as of :app:`Pyramid` 1.1. Use :class:`pyramid.static.static_view` instead (probably with a ``use_subpath=True`` argument). """ def __init__(self, root_dir, cache_max_age=3600, package_name=None): if package_name is None: package_name = caller_package().__name__ static_view.__init__(self, root_dir, cache_max_age=cache_max_age, package_name=package_name, use_subpath=True)
deprecated( 'static', 'The "pyramid.view.static" class is deprecated as of Pyramid 1.1; ' 'use the "pyramid.static.static_view" class instead with the ' '"use_subpath" argument set to True.')
[docs]def render_view_to_response(context, request, name='', secure=True): """ Call the :term:`view callable` configured with a :term:`view configuration` that matches the :term:`view name` ``name`` registered against the specified ``context`` and ``request`` and return a :term:`response` object. This function will return ``None`` if a corresponding :term:`view callable` cannot be found (when no :term:`view configuration` matches the combination of ``name`` / ``context`` / and ``request``). If `secure`` is ``True``, and the :term:`view callable` found is protected by a permission, the permission will be checked before calling the view function. If the permission check disallows view execution (based on the current :term:`authorization policy`), a :exc:`pyramid.httpexceptions.HTTPForbidden` exception will be raised. The exception's ``args`` attribute explains why the view access was disallowed. If ``secure`` is ``False``, no permission checking is done.""" provides = [IViewClassifier] + map_(providedBy, (request, context)) try: reg = request.registry except AttributeError: reg = get_current_registry() view = reg.adapters.lookup(provides, IView, name=name) if view is None: return None if not secure: # the view will have a __call_permissive__ attribute if it's # secured; otherwise it won't. view = getattr(view, '__call_permissive__', view) # if this view is secured, it will raise a Forbidden # appropriately if the executing user does not have the proper # permission return view(context, request)
[docs]def render_view_to_iterable(context, request, name='', secure=True): """ Call the :term:`view callable` configured with a :term:`view configuration` that matches the :term:`view name` ``name`` registered against the specified ``context`` and ``request`` and return an iterable object which represents the body of a response. This function will return ``None`` if a corresponding :term:`view callable` cannot be found (when no :term:`view configuration` matches the combination of ``name`` / ``context`` / and ``request``). Additionally, this function will raise a :exc:`ValueError` if a view function is found and called but the view function's result does not have an ``app_iter`` attribute. You can usually get the string representation of the return value of this function by calling ``''.join(iterable)``, or just use :func:`pyramid.view.render_view` instead. If ``secure`` is ``True``, and the view is protected by a permission, the permission will be checked before the view function is invoked. If the permission check disallows view execution (based on the current :term:`authentication policy`), a :exc:`pyramid.httpexceptions.HTTPForbidden` exception will be raised; its ``args`` attribute explains why the view access was disallowed. If ``secure`` is ``False``, no permission checking is done.""" response = render_view_to_response(context, request, name, secure) if response is None: return None return response.app_iter
[docs]def render_view(context, request, name='', secure=True): """ Call the :term:`view callable` configured with a :term:`view configuration` that matches the :term:`view name` ``name`` registered against the specified ``context`` and ``request`` and unwind the view response's ``app_iter`` (see :ref:`the_response`) into a single string. This function will return ``None`` if a corresponding :term:`view callable` cannot be found (when no :term:`view configuration` matches the combination of ``name`` / ``context`` / and ``request``). Additionally, this function will raise a :exc:`ValueError` if a view function is found and called but the view function's result does not have an ``app_iter`` attribute. This function will return ``None`` if a corresponding view cannot be found. If ``secure`` is ``True``, and the view is protected by a permission, the permission will be checked before the view is invoked. If the permission check disallows view execution (based on the current :term:`authorization policy`), a :exc:`pyramid.httpexceptions.HTTPForbidden` exception will be raised; its ``args`` attribute explains why the view access was disallowed. If ``secure`` is ``False``, no permission checking is done.""" iterable = render_view_to_iterable(context, request, name, secure) if iterable is None: return None return ''.join(iterable)
class _default(object): def __nonzero__(self): return False __bool__ = __nonzero__ def __repr__(self): # pragma: no cover return '(default)' default = _default()
[docs]class view_config(object): """ A function, class or method :term:`decorator` which allows a developer to create view registrations nearer to a :term:`view callable` definition than use :term:`imperative configuration` to do the same. For example, this code in a module ``views.py``:: from resources import MyResource @view_config(name='my_view', context=MyResource, permission='read', route_name='site1') def my_view(context, request): return 'OK' Might replace the following call to the :meth:`pyramid.config.Configurator.add_view` method:: import views from resources import MyResource config.add_view(views.my_view, context=MyResource, name='my_view', permission='read', 'route_name='site1') .. note: :class:`pyramid.view.view_config` is also importable, for backwards compatibility purposes, as the name :class:`pyramid.view.bfg_view`. The following arguments are supported to :class:`pyramid.view.view_config`: ``context``, ``permission``, ``name``, ``request_type``, ``route_name``, ``request_method``, ``request_param``, ``containment``, ``xhr``, ``accept``, ``header``, ``path_info``, ``custom_predicates``, ``decorator``, ``mapper``, ``http_cache``, and ``match_param``. The meanings of these arguments are the same as the arguments passed to :meth:`pyramid.config.Configurator.add_view`. If any argument is left out, its default will be the equivalent ``add_view`` default. See :ref:`mapping_views_using_a_decorator_section` for details about using :class:`view_config`. """ venusian = venusian # for testing injection def __init__(self, name=default, request_type=default, for_=default, permission=default, route_name=default, request_method=default, request_param=default, containment=default, attr=default, renderer=default, wrapper=default, xhr=default, accept=default, header=default, path_info=default, custom_predicates=default, context=default, decorator=default, mapper=default, http_cache=default, match_param=default): L = dict(locals()) # See issue #635 for dict() rationale if (context is not default) or (for_ is not default): L['context'] = context or for_ for k, v in L.items(): if k not in ('self', 'L') and v is not default: setattr(self, k, v) def __call__(self, wrapped): settings = self.__dict__.copy() def callback(context, name, ob): config = context.config.with_package(info.module) config.add_view(view=ob, **settings) info = self.venusian.attach(wrapped, callback, category='pyramid') if info.scope == 'class': # if the decorator was attached to a method in a class, or # otherwise executed at class scope, we need to set an # 'attr' into the settings if one isn't already in there if settings.get('attr') is None: settings['attr'] = wrapped.__name__ settings['_info'] = info.codeinfo # fbo "action_method" return wrapped
bfg_view = view_config # bw compat (forever)
[docs]class view_defaults(view_config): """ A class :term:`decorator` which, when applied to a class, will provide defaults for all view configurations that use the class. This decorator accepts all the arguments accepted by :class:`pyramid.config.view_config`, and each has the same meaning. See :ref:`view_defaults` for more information. """ def __call__(self, wrapped): wrapped.__view_defaults__ = self.__dict__.copy() return wrapped
class AppendSlashNotFoundViewFactory(object): """ There can only be one :term:`Not Found view` in any :app:`Pyramid` application. Even if you use :func:`pyramid.view.append_slash_notfound_view` as the Not Found view, :app:`Pyramid` still must generate a ``404 Not Found`` response when it cannot redirect to a slash-appended URL; this not found response will be visible to site users. If you don't care what this 404 response looks like, and you only need redirections to slash-appended route URLs, you may use the :func:`pyramid.view.append_slash_notfound_view` object as the Not Found view. However, if you wish to use a *custom* notfound view callable when a URL cannot be redirected to a slash-appended URL, you may wish to use an instance of this class as the Not Found view, supplying a :term:`view callable` to be used as the custom notfound view as the first argument to its constructor. For instance: .. code-block:: python from pyramid.httpexceptions import HTTPNotFound from pyramid.view import AppendSlashNotFoundViewFactory def notfound_view(context, request): return HTTPNotFound('nope') custom_append_slash = AppendSlashNotFoundViewFactory(notfound_view) config.add_view(custom_append_slash, context=HTTPNotFound) The ``notfound_view`` supplied must adhere to the two-argument view callable calling convention of ``(context, request)`` (``context`` will be the exception object). """ def __init__(self, notfound_view=None): if notfound_view is None: notfound_view = default_exceptionresponse_view self.notfound_view = notfound_view def __call__(self, context, request): path = decode_path_info(request.environ['PATH_INFO'] or '/') registry = request.registry mapper = registry.queryUtility(IRoutesMapper) if mapper is not None and not path.endswith('/'): slashpath = path + '/' for route in mapper.get_routes(): if route.match(slashpath) is not None: qs = request.query_string if qs: qs = '?' + qs return HTTPFound(location=request.path+'/'+qs) return self.notfound_view(context, request) append_slash_notfound_view = AppendSlashNotFoundViewFactory() append_slash_notfound_view.__doc__ = """\ For behavior like Django's ``APPEND_SLASH=True``, use this view as the :term:`Not Found view` in your application. When this view is the Not Found view (indicating that no view was found), and any routes have been defined in the configuration of your application, if the value of the ``PATH_INFO`` WSGI environment variable does not already end in a slash, and if the value of ``PATH_INFO`` *plus* a slash matches any route's path, do an HTTP redirect to the slash-appended PATH_INFO. Note that this will *lose* ``POST`` data information (turning it into a GET), so you shouldn't rely on this to redirect POST requests. Note also that static routes are not considered when attempting to find a matching route. Use the :meth:`pyramid.config.Configurator.add_view` method to configure this view as the Not Found view:: from pyramid.httpexceptions import HTTPNotFound from pyramid.view import append_slash_notfound_view config.add_view(append_slash_notfound_view, context=HTTPNotFound) See also :ref:`changing_the_notfound_view`. """
[docs]class notfound_view_config(object): """ An analogue of :class:`pyramid.view.view_config` which registers a :term:`not found view`. The notfound_view_config constructor accepts most of the same arguments as the constructor of :class:`pyramid.view.view_config`. It can be used in the same places, and behaves in largely the same way, except it always registers a not found exception view instead of a "normal" view. Example: .. code-block:: python from pyramid.view import notfound_view_config from pyramid.response import Response notfound_view_config() def notfound(request): return Response('Not found, dude!', status='404 Not Found') All arguments except ``append_slash`` have the same meaning as :meth:`pyramid.view.view_config` and each predicate argument restricts the set of circumstances under which this notfound view will be invoked. If ``append_slash`` is ``True``, when the notfound view is invoked, and the current path info does not end in a slash, the notfound logic will attempt to find a :term:`route` that matches the request's path info suffixed with a slash. If such a route exists, Pyramid will issue a redirect to the URL implied by the route; if it does not, Pyramid will return the result of the view callable provided as ``view``, as normal. See :ref:`changing_the_notfound_view` for detailed usage information. .. note:: This class is new as of Pyramid 1.3. """ venusian = venusian def __init__(self, request_type=default, request_method=default, route_name=default, request_param=default, attr=default, renderer=default, containment=default, wrapper=default, xhr=default, accept=default, header=default, path_info=default, custom_predicates=default, decorator=default, mapper=default, match_param=default, append_slash=False): L = dict(locals()) # See issue #635 for dict() rationale for k, v in L.items(): if k not in ('self', 'L') and v is not default: self.__dict__[k] = v def __call__(self, wrapped): settings = self.__dict__.copy() def callback(context, name, ob): config = context.config.with_package(info.module) config.add_notfound_view(view=ob, **settings) info = self.venusian.attach(wrapped, callback, category='pyramid') if info.scope == 'class': # if the decorator was attached to a method in a class, or # otherwise executed at class scope, we need to set an # 'attr' into the settings if one isn't already in there if settings.get('attr') is None: settings['attr'] = wrapped.__name__ settings['_info'] = info.codeinfo # fbo "action_method" return wrapped
[docs]class forbidden_view_config(object): """ An analogue of :class:`pyramid.view.view_config` which registers a :term:`forbidden view`. The forbidden_view_config constructor accepts most of the same arguments as the constructor of :class:`pyramid.view.view_config`. It can be used in the same places, and behaves in largely the same way, except it always registers a forbidden exception view instead of a "normal" view. Example: .. code-block:: python from pyramid.view import forbidden_view_config from pyramid.response import Response forbidden_view_config() def notfound(request): return Response('You are not allowed', status='401 Unauthorized') All have the same meaning as :meth:`pyramid.view.view_config` and each predicate argument restricts the set of circumstances under which this notfound view will be invoked. See :ref:`changing_the_forbidden_view` for detailed usage information. .. note:: This class is new as of Pyramid 1.3. """ venusian = venusian def __init__(self, request_type=default, request_method=default, route_name=default, request_param=default, attr=default, renderer=default, containment=default, wrapper=default, xhr=default, accept=default, header=default, path_info=default, custom_predicates=default, decorator=default, mapper=default, match_param=default): L = dict(locals()) # See issue #635 for dict() rationale for k, v in L.items(): if k not in ('self', 'L') and v is not default: self.__dict__[k] = v def __call__(self, wrapped): settings = self.__dict__.copy() def callback(context, name, ob): config = context.config.with_package(info.module) config.add_forbidden_view(view=ob, **settings) info = self.venusian.attach(wrapped, callback, category='pyramid') if info.scope == 'class': # if the decorator was attached to a method in a class, or # otherwise executed at class scope, we need to set an # 'attr' into the settings if one isn't already in there if settings.get('attr') is None: settings['attr'] = wrapped.__name__ settings['_info'] = info.codeinfo # fbo "action_method" return wrapped
[docs]def is_response(ob): """ Return ``True`` if ``ob`` implements the interface implied by :ref:`the_response`. ``False`` if not. .. warning:: This function is deprecated as of :app:`Pyramid` 1.1. New code should not use it. Instead, new code should use the :func:`pyramid.request.Request.is_response` method.""" if ( hasattr(ob, 'app_iter') and hasattr(ob, 'headerlist') and hasattr(ob, 'status') ): return True return False
deprecated( 'is_response', 'pyramid.view.is_response is deprecated as of Pyramid 1.1. Use ' 'pyramid.request.Request.is_response instead.')