import os
import pkg_resources
import threading
from zope.interface import implements
from zope.deprecation import deprecated
from pyramid.interfaces import IChameleonLookup
from pyramid.interfaces import IChameleonTranslate
from pyramid.interfaces import IRendererGlobalsFactory
from pyramid.interfaces import IRendererFactory
from pyramid.interfaces import IResponseFactory
from pyramid.interfaces import ITemplateRenderer
from pyramid.interfaces import IRendererInfo
from pyramid.asset import asset_spec_from_abspath
from pyramid.compat import json
from pyramid.decorator import reify
from pyramid.events import BeforeRender
from pyramid.path import caller_package
from pyramid.path import package_path
from pyramid.response import Response
from pyramid.threadlocal import get_current_registry
# API
[docs]def render(renderer_name, value, request=None, package=None):
""" Using the renderer specified as ``renderer_name`` (a template
or a static renderer) render the value (or set of values) present
in ``value``. Return the result of the renderer's ``__call__``
method (usually a string or Unicode).
If the renderer name refers to a file on disk (such as when the
renderer is a template), it's usually best to supply the name as a
:term:`asset specification`
(e.g. ``packagename:path/to/template.pt``).
You may supply a relative asset spec as ``renderer_name``. If
the ``package`` argument is supplied, a relative renderer path
will be converted to an absolute asset specification by
combining the package supplied as ``package`` with the relative
asset specification supplied as ``renderer_name``. If you do
not supply a ``package`` (or ``package`` is ``None``) the package
name of the *caller* of this function will be used as the package.
The ``value`` provided will be supplied as the input to the
renderer. Usually, for template renderings, this should be a
dictionary. For other renderers, this will need to be whatever
sort of value the renderer expects.
The 'system' values supplied to the renderer will include a basic
set of top-level system names, such as ``request``, ``context``,
and ``renderer_name``. If :term:`renderer globals` have been
specified, these will also be used to agument the value.
Supply a ``request`` parameter in order to provide the renderer
with the most correct 'system' values (``request`` and ``context``
in particular).
"""
try:
registry = request.registry
except AttributeError:
registry = None
if package is None:
package = caller_package()
helper = RendererHelper(name=renderer_name, package=package,
registry=registry)
return helper.render(value, None, request=request)
[docs]def render_to_response(renderer_name, value, request=None, package=None):
""" Using the renderer specified as ``renderer_name`` (a template
or a static renderer) render the value (or set of values) using
the result of the renderer's ``__call__`` method (usually a string
or Unicode) as the response body.
If the renderer name refers to a file on disk (such as when the
renderer is a template), it's usually best to supply the name as a
:term:`asset specification`.
You may supply a relative asset spec as ``renderer_name``. If
the ``package`` argument is supplied, a relative renderer name
will be converted to an absolute asset specification by
combining the package supplied as ``package`` with the relative
asset specification supplied as ``renderer_name``. If you do
not supply a ``package`` (or ``package`` is ``None``) the package
name of the *caller* of this function will be used as the package.
The ``value`` provided will be supplied as the input to the
renderer. Usually, for template renderings, this should be a
dictionary. For other renderers, this will need to be whatever
sort of value the renderer expects.
The 'system' values supplied to the renderer will include a basic
set of top-level system names, such as ``request``, ``context``,
and ``renderer_name``. If :term:`renderer globals` have been
specified, these will also be used to agument the value.
Supply a ``request`` parameter in order to provide the renderer
with the most correct 'system' values (``request`` and ``context``
in particular).
"""
try:
registry = request.registry
except AttributeError:
registry = None
if package is None:
package = caller_package()
helper = RendererHelper(name=renderer_name, package=package,
registry=registry)
return helper.render_to_response(value, None, request=request)
[docs]def get_renderer(renderer_name, package=None):
""" Return the renderer object for the renderer named as
``renderer_name``.
You may supply a relative asset spec as ``renderer_name``. If
the ``package`` argument is supplied, a relative renderer name
will be converted to an absolute asset specification by
combining the package supplied as ``package`` with the relative
asset specification supplied as ``renderer_name``. If you do
not supply a ``package`` (or ``package`` is ``None``) the package
name of the *caller* of this function will be used as the package.
"""
if package is None:
package = caller_package()
helper = RendererHelper(name=renderer_name, package=package)
return helper.renderer
# concrete renderer factory implementations (also API)
def json_renderer_factory(info):
def _render(value, system):
request = system.get('request')
if request is not None:
response = request.response
ct = response.content_type
if ct == response.default_content_type:
response.content_type = 'application/json'
return json.dumps(value)
return _render
def string_renderer_factory(info):
def _render(value, system):
if not isinstance(value, basestring):
value = str(value)
request = system.get('request')
if request is not None:
response = request.response
ct = response.content_type
if ct == response.default_content_type:
response.content_type = 'text/plain'
return value
return _render
[docs]class JSONP(object):
""" `JSONP <http://en.wikipedia.org/wiki/JSONP>`_ renderer factory helper
which implements a hybrid json/jsonp renderer. JSONP is useful for
making cross-domain AJAX requests.
Configure a JSONP renderer using the
:meth:`pyramid.config.Configurator.add_renderer` API at application
startup time:
.. code-block:: python
from pyramid.config import Configurator
config = Configurator()
config.add_renderer('jsonp', JSONP(param_name='callback'))
Once this renderer is registered via
:meth:`~pyramid.config.Configurator.add_renderer` as above, you can use
``jsonp`` as the ``renderer=`` parameter to ``@view_config`` or
:meth:`pyramid.config.Configurator.add_view``:
.. code-block:: python
from pyramid.view import view_config
@view_config(renderer='jsonp')
def myview(request):
return {'greeting':'Hello world'}
When a view is called that uses the JSONP renderer:
- If there is a parameter in the request's HTTP query string that matches
the ``param_name`` of the registered JSONP renderer (by default,
``callback``), the renderer will return a JSONP response.
- If there is no callback parameter in the request's query string, the
renderer will return a 'plain' JSON response.
.. note:: This feature is new in Pyramid 1.1.
See also: :ref:`jsonp_renderer`.
"""
def __init__(self, param_name='callback'):
self.param_name = param_name
def __call__(self, info):
""" Returns JSONP-encoded string with content-type
``application/javascript`` if query parameter matching
``self.param_name`` is present in request.GET; otherwise returns
plain-JSON encoded string with content-type ``application/json``"""
def _render(value, system):
request = system['request']
val = json.dumps(value)
callback = request.GET.get(self.param_name)
if callback is None:
ct = 'application/json'
body = val
else:
ct = 'application/javascript'
body = '%s(%s)' % (callback, val)
response = request.response
if response.content_type == response.default_content_type:
response.content_type = ct
return body
return _render
# utility functions, not API
class ChameleonRendererLookup(object):
implements(IChameleonLookup)
def __init__(self, impl, registry):
self.impl = impl
self.registry = registry
self.lock = threading.Lock()
def get_spec(self, name, package):
if not package:
# if there's no package, we can't do any conversion
return name
spec = name
isabspath = os.path.isabs(name)
colon_in_name = ':' in name
isabsspec = colon_in_name and (not isabspath)
isrelspec = (not isabsspec) and (not isabspath)
# if it's already an absolute spec, we don't need to do anything,
# but if it's a relative spec or an absolute path, we need to try
# to convert it to an absolute spec
if isrelspec:
# convert relative asset spec to absolute asset spec
pp = package_path(package)
spec = os.path.join(pp, spec)
spec = asset_spec_from_abspath(spec, package)
elif isabspath:
# convert absolute path to absolute asset spec
spec = asset_spec_from_abspath(spec, package)
return spec
@property # wait until completely necessary to look up translator
def translate(self):
return self.registry.queryUtility(IChameleonTranslate)
@property # wait until completely necessary to look up debug_templates
def debug(self):
settings = self.registry.settings
if settings is None:
return False
return settings.get('debug_templates', False)
@property # wait until completely necessary to look up reload_templates
def auto_reload(self):
settings = self.registry.settings
if settings is None:
return False
return settings.get('reload_templates', False)
def __call__(self, info):
spec = self.get_spec(info.name, info.package)
registry = info.registry
if os.path.isabs(spec):
# 'spec' is an absolute filename
if not os.path.exists(spec):
raise ValueError('Missing template file: %s' % spec)
renderer = registry.queryUtility(ITemplateRenderer, name=spec)
if renderer is None:
renderer = self.impl(spec, self)
# cache the template
try:
self.lock.acquire()
registry.registerUtility(renderer,
ITemplateRenderer, name=spec)
finally:
self.lock.release()
else:
# spec is a package:relpath asset spec
renderer = registry.queryUtility(ITemplateRenderer, name=spec)
if renderer is None:
try:
package_name, filename = spec.split(':', 1)
except ValueError: # pragma: no cover
# somehow we were passed a relative pathname; this
# should die
package_name = caller_package(4).__name__
filename = spec
abspath = pkg_resources.resource_filename(package_name,
filename)
if not pkg_resources.resource_exists(package_name, filename):
raise ValueError(
'Missing template asset: %s (%s)' % (spec, abspath))
renderer = self.impl(abspath, self)
settings = info.settings
if not settings.get('reload_assets'):
# cache the template
self.lock.acquire()
try:
registry.registerUtility(renderer, ITemplateRenderer,
name=spec)
finally:
self.lock.release()
return renderer
registry_lock = threading.Lock()
def template_renderer_factory(info, impl, lock=registry_lock):
registry = info.registry
lookup = registry.queryUtility(IChameleonLookup, name=info.type)
if lookup is None:
lookup = ChameleonRendererLookup(impl, registry)
lock.acquire()
try:
registry.registerUtility(lookup, IChameleonLookup, name=info.type)
finally:
lock.release()
return lookup(info)
def renderer_from_name(path, package=None):
return RendererHelper(name=path, package=package).renderer
deprecated(
'renderer_from_name',
'The "pyramid.renderers.renderer_from_name" function was never an API. '
'However, its use has been observed "in the wild." It will disappear in '
'the next major release. To replace it, use the '
'``pyramid.renderers.get_renderer`` API instead. ')
class RendererHelper(object):
implements(IRendererInfo)
def __init__(self, name=None, package=None, registry=None):
if name and '.' in name:
rtype = os.path.splitext(name)[1]
else:
# important.. must be a string; cannot be None; see issue 249
rtype = name or ''
if registry is None:
registry = get_current_registry()
self.name = name
self.package = package
self.type = rtype
self.registry = registry
@reify
def settings(self):
settings = self.registry.settings
if settings is None:
settings = {}
return settings
@reify
def renderer(self):
factory = self.registry.queryUtility(IRendererFactory, name=self.type)
if factory is None:
raise ValueError(
'No such renderer factory %s' % str(self.type))
return factory(self)
def get_renderer(self):
return self.renderer
def render_view(self, request, response, view, context):
system = {
'view':view,
'renderer_name':self.name, # b/c
'renderer_info':self,
'context':context,
'request':request
}
return self.render_to_response(response, system, request=request)
def render(self, value, system_values, request=None):
renderer = self.renderer
if system_values is None:
system_values = {
'view':None,
'renderer_name':self.name, # b/c
'renderer_info':self,
'context':getattr(request, 'context', None),
'request':request,
}
registry = self.registry
globals_factory = registry.queryUtility(IRendererGlobalsFactory)
if globals_factory is not None:
renderer_globals = globals_factory(system_values)
if renderer_globals:
system_values.update(renderer_globals)
registry.notify(BeforeRender(system_values))
result = renderer(value, system_values)
return result
def render_to_response(self, value, system_values, request=None):
result = self.render(value, system_values, request=request)
return self._make_response(result, request)
def _make_response(self, result, request):
# broken out of render_to_response as a separate method for testing
# purposes
response = getattr(request, 'response', None)
if response is None:
# request is None or request is not a pyramid.response.Response
registry = self.registry
response_factory = registry.queryUtility(IResponseFactory,
default=Response)
response = response_factory()
if result is None:
result = ''
if isinstance(result, unicode):
response.unicode_body = result
else:
response.body = result
if request is not None:
# deprecated mechanism to set up request.response_* attrs, see
# pyramid.request.Request
attrs = request.__dict__
content_type = attrs.get('_response_content_type', None)
if content_type is not None:
response.content_type = content_type
headerlist = attrs.get('_response_headerlist', None)
if headerlist is not None:
for k, v in headerlist:
response.headers.add(k, v)
status = attrs.get('_response_status', None)
if status is not None:
response.status = status
charset = attrs.get('_response_charset', None)
if charset is not None:
response.charset = charset
cache_for = attrs.get('_response_cache_for', None)
if cache_for is not None:
response.cache_expires = cache_for
return response
def clone(self, name=None, package=None, registry=None):
if name is None:
name = self.name
if package is None:
package = self.package
if registry is None:
registry = self.registry
return self.__class__(name=name, package=package, registry=registry)
class NullRendererHelper(RendererHelper):
""" Special renderer helper that has render_* methods which simply return
the value they are fed rather than converting them to response objects;
useful for testing purposes and special case view configuration
registrations that want to use the view configuration machinery but do
not want actual rendering to happen ."""
def render_view(self, request, value, view, context):
return value
def render(self, value, system_values, request=None):
return value
def render_to_response(self, value, system_values, request=None):
return value
def clone(self, name=None, package=None, registry=None):
return self
null_renderer = NullRendererHelper()
