The Pyramid web application development framework, a Pylons project
Pyramid is a small, fast, down-to-earth, open source Python web application development framework. It makes real-world web application development and deployment more fun, more predictable, and more productive.
Pyramid is the newest web framework produced by the Pylons Project.
Support and Documentation
See the Pylons Project website to view documentation, report bugs, and obtain support.
Pyramid is offered under the BSD-derived Repoze Public License.
- When a renderers= argument is not specified to the Configurator constructor, eagerly register and commit the default renderer set. This permits the overriding of the default renderers, which was broken in 1.2a1 without a commit directly after Configurator construction.
- Mako rendering exceptions had the wrong value for an error message.
- An include could not set a root factory successfully because the Configurator constructor unconditionally registered one that would be treated as if it were “the word of the user”.
- A session factory can now be passed in using the dotted name syntax.
The [pshell] section in an ini configuration file now treats a setup key as a dotted name that points to a callable that is passed the bootstrap environment. It can mutate the environment as necessary for great justice.
A new configuration setting named pyramid.includes is now available. It is described in the “Environment Variables and .ini Files Settings” narrative documentation chapter.
Added a route_prefix argument to the pyramid.config.Configurator.include method. This argument allows you to compose URL dispatch applications together. See the section entitled “Using a Route Prefix to Compose Applications” in the “URL Dispatch” narrative documentation chapter.
Added a pyramid.security.NO_PERMISSION_REQUIRED constant for use in permission= statements to view configuration. This constant has a value of the string __no_permission_required__. This string value was previously referred to in documentation; now the documentation uses the constant.
Added a decorator-based way to configure a response adapter: pyramid.response.response_adapter. This decorator has the same use as pyramid.config.Configurator.add_response_adapter but it’s declarative.
The pyramid.events.BeforeRender event now has an attribute named rendering_val. This can be used to introspect the value returned by a view in a BeforeRender subscriber.
New configurator directive: pyramid.config.Configurator.add_tween. This directive adds a “tween”. A “tween” is used to wrap the Pyramid router’s primary request handling function. This is a feature may be used by Pyramid framework extensions, to provide, for example, view timing support and as a convenient place to hang bookkeeping code.
Tweens are further described in the narrative docs section in the Hooks chapter, named “Registering Tweens”.
New paster command paster ptweens, which prints the current “tween” configuration for an application. See the section entitled “Displaying Tweens” in the Command-Line Pyramid chapter of the narrative documentation for more info.
The Pyramid debug logger now uses the standard logging configuration (usually set up by Paste as part of startup). This means that output from e.g. debug_notfound, debug_authorization, etc. will go to the normal logging channels. The logger name of the debug logger will be the package name of the caller of the Configurator’s constructor.
A new attribute is available on request objects: exc_info. Its value will be None until an exception is caught by the Pyramid router, after which it will be the result of sys.exc_info().
pyramid.testing.DummyRequest now implements the add_finished_callback and add_response_callback methods.
New methods of the pyramid.config.Configurator class: set_authentication_policy and set_authorization_policy. These are meant to be consumed mostly by add-on authors.
New Configurator method: set_root_factory.
Pyramid no longer eagerly commits some default configuration statements at Configurator construction time, which permits values passed in as constructor arguments (e.g. authentication_policy and authorization_policy) to override the same settings obtained via an “include”.
Better Mako rendering exceptions via pyramid.mako_templating.MakoRenderingException
New request methods: current_route_url, current_route_path, and static_path.
New functions in pyramid.url: current_route_path and static_path.
The pyramid.request.Request.static_url API (and its brethren pyramid.request.Request.static_path, pyramid.url.static_url, and pyramid.url.static_path) now accept an asbolute filename as a “path” argument. This will generate a URL to an asset as long as the filename is in a directory which was previously registered as a static view. Previously, trying to generate a URL to an asset using an absolute file path would raise a ValueError.
The RemoteUserAuthenticationPolicy ``, ``AuthTktAuthenticationPolicy, and SessionAuthenticationPolicy constructors now accept an additional keyword argument named debug. By default, this keyword argument is False. When it is True, debug information will be sent to the Pyramid debug logger (usually on stderr) when the authenticated_userid or effective_principals method is called on any of these policies. The output produced can be useful when trying to diagnose authentication-related problems.
New view predicate: match_param. Example: a view added via config.add_view(aview, match_param='action=edit') will be called only when the request.matchdict has a value inside it named action with a value of edit.
- The Pyramid “exception view” machinery is now implemented as a “tween” (pyramid.tweens.excview_tween_factory).
- WSGIHTTPException (HTTPFound, HTTPNotFound, etc) now has a new API named “prepare” which renders the body and content type when it is provided with a WSGI environ. Required for debug toolbar.
- Once __call__ or prepare is called on a WSGIHTTPException, the body will be set, and subsequent calls to __call__ will always return the same body. Delete the body attribute to rerender the exception body.
- Previously the pyramid.events.BeforeRender event wrapped a dictionary (it addressed it as its _system attribute). Now it is a dictionary (it inherits from dict), and it’s the value that is passed to templates as a top-level dictionary.
- The route_url, route_path, resource_url, static_url, and current_route_url functions in the pyramid.url package now delegate to a method on the request they’ve been passed, instead of the other way around. The pyramid.request.Request object now inherits from a mixin named pyramid.url.URLMethodsMixin to make this possible, and all url/path generation logic is embedded in this mixin.
- Refactor pyramid.config into a package.
- Removed the _set_security_policies method of the Configurator.
- Moved the StaticURLInfo class from pyramid.static to pyramid.config.views.
- Move the Settings class from pyramid.settings to pyramid.config.settings.
- Move the OverrideProvider, PackageOverrides, DirectoryOverride, and FileOverride classes from pyramid.asset to pyramid.config.assets.
- All Pyramid-related deployment settings (e.g. debug_all, debug_notfound) are now meant to be prefixed with the prefix pyramid.. For example: debug_all -> pyramid.debug_all. The old non-prefixed settings will continue to work indefinitely but supplying them may eventually print a deprecation warning. All scaffolds and tutorials have been changed to use prefixed settings.
- The settings dictionary now raises a deprecation warning when you attempt to access its values via __getattr__ instead of via __getitem__.
If a string is passed as the debug_logger parameter to a Configurator, that string is considered to be the name of a global Python logger rather than a dotted name to an instance of a logger.
The pyramid.config.Configurator.include method now accepts only a single callable argument (a sequence of callables used to be permitted). If you are passing more than one callable to pyramid.config.Configurator.include, it will break. You now must now instead make a separate call to the method for each callable. This change was introduced to support the route_prefix feature of include.
It may be necessary to more strictly order configuration route and view statements when using an “autocommitting” Configurator. In the past, it was possible to add a view which named a route name before adding a route with that name when you used an autocommitting configurator. For example:
config = Configurator(autocommit=True) config.add_view('my.pkg.someview', route_name='foo') config.add_route('foo', '/foo')
The above will raise an exception when the view attempts to add itself. Now you must add the route before adding the view:
config = Configurator(autocommit=True) config.add_route('foo', '/foo') config.add_view('my.pkg.someview', route_name='foo')
This won’t effect “normal” users, only people who have legacy BFG codebases that used an autommitting configurator and possibly tests that use the configurator API (the configurator returned by pyramid.testing.setUp is an autocommitting configurator). The right way to get around this is to use a non-autocommitting configurator (the default), which does not have these directive ordering requirements.
The pyramid.config.Configurator.add_route directive no longer returns a route object. This change was required to make route vs. view configuration processing work properly.
- Narrative and API documentation which used the route_url, route_path, resource_url, static_url, and current_route_url functions in the pyramid.url package have now been changed to use eponymous methods of the request instead.
- Added a section entitled “Using a Route Prefix to Compose Applications” to the “URL Dispatch” narrative documentation chapter.
- Added a new module to the API docs: pyramid.tweens.
- Added a “Registering Tweens” section to the “Hooks” narrative chapter.
- Added a “Displaying Tweens” section to the “Command-Line Pyramid” narrative chapter.
- Added documentation for the pyramid.tweens and pyramid.includes configuration settings to the “Environment Variables and .ini Files Settings” chapter.
- Added a Logging chapter to the narrative docs (based on the Pylons logging docs, thanks Phil).
- Added a Paste chapter to the narrative docs (moved content from the Project chapter).
- Added the pyramid.interfaces.IDict interface representing the methods of a dictionary, for documentation purposes only (IMultiDict and IBeforeRender inherit from it).
- All tutorials now use - The route_url, route_path, resource_url, static_url, and current_route_url methods of the request rather than the function variants imported from pyramid.url.
- The ZODB wiki tutorial now uses the pyramid_zodbconn package rather than the repoze.zodbconn package to provide ZODB integration.
- Pyramid now relies on PasteScript >= 1.7.4. This version contains a feature important for allowing flexible logging configuration.
- All scaffolds now use the pyramid_tm package rather than the repoze.tm2 middleware to manage transaction management.
- The ZODB scaffold now uses the pyramid_zodbconn package rather than the repoze.zodbconn package to provide ZODB integration.
- All scaffolds now use the pyramid_debugtoolbar package rather than the WebError package to provide interactive debugging features.
- Projects created via a scaffold no longer depend on the WebError package at all; configuration in the production.ini file which used to require its error_catcher middleware has been removed. Configuring error catching / email sending is now the domain of the pyramid_exclog package (see https://docs.pylonsproject.org/projects/pyramid_exclog/dev/).
- Fixed an issue with the default renderer not working at certain times. See https://github.com/Pylons/pyramid/issues/249