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 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 pyramid.wsgi.wsgiapp2 calls the downstream WSGI app, the app’s environ will no longer have (deprecated and potentially misleading) bfg.routes.matchdict or bfg.routes.route keys in it. A symptom of this bug would be a wsgiapp2-wrapped Pyramid app finding the wrong view because it mistakenly detects that a route was matched when, in fact, it was not.
- The fix for issue https://github.com/Pylons/pyramid/issues/461 (which made it possible for instance methods to be used as view callables) introduced a backwards incompatibility when methods that declared only a request argument were used. See https://github.com/Pylons/pyramid/issues/503
- config.add_view(<aninstancemethod>) raised AttributeError involving __text__. See https://github.com/Pylons/pyramid/issues/461
- Remove references to do-nothing pyramid.debug_templates setting in all Pyramid-provided .ini files. This setting previously told Chameleon to render better exceptions; now Chameleon always renders nice exceptions regardless of the value of this setting.
- The alchemy scaffold now shows an informative error message in the browser if the person creating the project forgets to run the initialization script.
- The alchemy scaffold initialization script is now called initialize_<projectname>_db instead of populate_<projectname>.
- Wiki tutorials improved due to collaboration at PyCon US 2012 sprints.
The method pyramid.request.Request.partial_application_url is no longer in the API docs. It was meant to be a private method; its publication in the documentation as an API method was a mistake, and it has been renamed to something private.
When a static view was registered using an absolute filesystem path on Windows, the request.static_url function did not work to generate URLs to its resources. Symptom: “No static URL definition matching c:\foo\bar\baz”.
Make all tests pass on Windows XP.
Bug in ACL authentication checking on Python 3: the permits and principals_allowed_by_permission method of pyramid.authorization.ACLAuthenticationPolicy could return an inappropriate True value when a permission on an ACL was a string rather than a sequence, and then only if the ACL permission string was a substring of the permission value passed to the function.
This bug effects no Pyramid deployment under Python 2; it is a bug that exists only in deployments running on Python 3. It has existed since Pyramid 1.3a1.
This bug was due to the presence of an __iter__ attribute on strings under Python 3 which is not present under strings in Python 2.
- pyramid.config.Configurator.with_package didn’t work if the Configurator was an old-style pyramid.configuration.Configurator instance.
- Pyramid authorization policies did not show up in the introspector.
- All references to the tmpl_context request variable were removed from the docs. Its existence in Pyramid is confusing for people who were never Pylons users. It was added as a porting convenience for Pylons users in Pyramid 1.0, but it never caught on because the Pyramid rendering system is a lot different than Pylons’ was, and alternate ways exist to do what it was designed to offer in Pylons. It will continue to exist “forever” but it will not be recommended or mentioned in the docs.
- Add an introspection boolean to the Configurator constructor. If this is True, actions registered using the Configurator will be registered with the introspector. If it is False, they won’t. The default is True. Setting it to False during action processing will prevent introspection for any following registration statements, and setting it to True will start them up again. This addition is to service a requirement that the debug toolbar’s own views and methods not show up in the introspector.
- New API: pyramid.config.Configurator.add_notfound_view. This is a wrapper for pyramid.Config.configurator.add_view which provides easy append_slash support and does the right thing about permissions. It should be preferred over calling add_view directly with context=HTTPNotFound as was previously recommended.
- New API: pyramid.view.notfound_view_config. This is a decorator constructor like pyramid.view.view_config that calls pyramid.config.Configurator.add_notfound_view when scanned. It should be preferred over using pyramid.view.view_config with context=HTTPNotFound as was previously recommended.
- New API: pyramid.config.Configurator.add_forbidden_view. This is a wrapper for pyramid.Config.configurator.add_view which does the right thing about permissions. It should be preferred over calling add_view directly with context=HTTPForbidden as was previously recommended.
- New API: pyramid.view.forbidden_view_config. This is a decorator constructor like pyramid.view.view_config that calls pyramid.config.Configurator.add_forbidden_view when scanned. It should be preferred over using pyramid.view.view_config with context=HTTPForbidden as was previously recommended.
- New APIs: pyramid.response.FileResponse and pyramid.response.FileIter, for usage in views that must serve files “manually”.
- Remove pyramid.config.Configurator.with_context class method. It was never an API, it is only used by pyramid_zcml and its functionality has been moved to that package’s latest release. This means that you’ll need to use the 0.9.2 or later release of pyramid_zcml with this release of Pyramid.
- The introspector argument to the pyramid.config.Configurator constructor API has been removed. It has been replaced by the boolean introspection flag.
- The pyramid.registry.noop_introspector API object has been removed.
- The older deprecated set_notfound_view Configurator method is now an alias for the new add_notfound_view Configurator method. Likewise, the older deprecated set_forbidden_view is now an alias for the new add_forbidden_view. This has the following impact: the context sent to views with a (context, request) call signature registered via the set_notfound_view or set_forbidden_view will now be an exception object instead of the actual resource context found. Use request.context to get the actual resource context. It’s also recommended to disuse set_notfound_view in favor of add_notfound_view, and disuse set_forbidden_view in favor of add_forbidden_view despite the aliasing.
- The API documentation for pyramid.view.append_slash_notfound_view and pyramid.view.AppendSlashNotFoundViewFactory was removed. These names still exist and are still importable, but they are no longer APIs. Use pyramid.config.Configurator.add_notfound_view(append_slash=True) or pyramid.view.notfound_view_config(append_slash=True) to get the same behavior.
- The set_forbidden_view and set_notfound_view methods of the Configurator were removed from the documentation. They have been deprecated since Pyramid 1.1.
- The static file response object used by config.add_static_view opened the static file twice, when it only needed to open it once.
- The AppendSlashNotFoundViewFactory used request.path to match routes. This was wrong because request.path contains the script name, and this would cause it to fail in circumstances where the script name was not empty. It should have used request.path_info, and now does.
- Updated the “Creating a Not Found View” section of the “Hooks” chapter, replacing explanations of registering a view using add_view or view_config with ones using add_notfound_view or notfound_view_config.
- Updated the “Creating a Not Forbidden View” section of the “Hooks” chapter, replacing explanations of registering a view using add_view or view_config with ones using add_forbidden_view or forbidden_view_config.
- Updated the “Redirecting to Slash-Appended Routes” section of the “URL Dispatch” chapter, replacing explanations of registering a view using add_view or view_config with ones using add_notfound_view or notfound_view_config
- Updated all tutorials to use pyramid.view.forbidden_view_config rather than pyramid.view.view_config with an HTTPForbidden context.
- The scan method of a Configurator can be passed an ignore argument, which can be a string, a callable, or a list consisting of strings and/or callables. This feature allows submodules, subpackages, and global objects from being scanned. See http://readthedocs.org/docs/venusian/en/latest/#ignore-scan-argument for more information about how to use the ignore argument to scan.
- Better error messages when a view callable returns a value that cannot be converted to a response (for example, when a view callable returns a dictionary without a renderer defined, or doesn’t return any value at all). The error message now contains information about the view callable itself as well as the result of calling it.
- Better error message when a .pyc-only module is config.include -ed. This is not permitted due to error reporting requirements, and a better error message is shown when it is attempted. Previously it would fail with something like “AttributeError: ‘NoneType’ object has no attribute ‘rfind’”.
- Add pyramid.config.Configurator.add_traverser API method. See the Hooks narrative documentation section entitled “Changing the Traverser” for more information. This is not a new feature, it just provides an API for adding a traverser without needing to use the ZCA API.
- Add pyramid.config.Configurator.add_resource_url_adapter API method. See the Hooks narrative documentation section entitled “Changing How pyramid.request.Request.resource_url Generates a URL” for more information. This is not a new feature, it just provides an API for adding a resource url adapter without needing to use the ZCA API.
- The system value req is now supplied to renderers as an alias for request. This means that you can now, for example, in a template, do req.route_url(...) instead of request.route_url(...). This is purely a change to reduce the amount of typing required to use request methods and attributes from within templates. The value request is still available too, this is just an alternative.
- A new interface was added: pyramid.interfaces.IResourceURL. An adapter implementing its interface can be used to override resource URL generation when request.resource_url is called. This interface replaces the now-deprecated pyramid.interfaces.IContextURL interface.
- The dictionary passed to a resource’s __resource_url__ method (see “Overriding Resource URL Generation” in the “Resources” chapter) now contains an app_url key, representing the application URL generated during request.resource_url. It represents a potentially customized URL prefix, containing potentially custom scheme, host and port information passed by the user to request.resource_url. It should be used instead of request.application_url where necessary.
- The request.resource_url API now accepts these arguments: app_url, scheme, host, and port. The app_url argument can be used to replace the URL prefix wholesale during url generation. The scheme, host, and port arguments can be used to replace the respective default values of request.application_url partially.
- A new API named request.resource_path now exists. It works like request.resource_url but produces a relative URL rather than an absolute one.
- The request.route_url API now accepts these arguments: _app_url, _scheme, _host, and _port. The _app_url argument can be used to replace the URL prefix wholesale during url generation. The _scheme, _host, and _port arguments can be used to replace the respective default values of request.application_url partially.
The pyramid.interfaces.IContextURL interface has been deprecated. People have been instructed to use this to register a resource url adapter in the “Hooks” chapter to use to influence request.resource_url URL generation for resources found via custom traversers since Pyramid 1.0.
The interface still exists and registering such an adapter still works, but this interface will be removed from the software after a few major Pyramid releases. You should replace it with an equivalent pyramid.interfaces.IResourceURL adapter, registered using the new pyramid.config.Configurator.add_resource_url_adapter API. A deprecation warning is now emitted when a pyramid.interfaces.IContextURL adapter is found when request.resource_url is called.
- Don’t create a session instance in SQLA Wiki tutorial, use raw DBSession instead (this is more common in real SQLA apps).
- Put pyramid.includes targets within ini files in scaffolds on separate lines in order to be able to tell people to comment out only the pyramid_debugtoolbar line when they want to disable the toolbar.
- Depend on venusian >= 1.0a3 to provide scan ignore support.
- Create a “MakoRendererFactoryHelper” that provides customizable settings key prefixes. Allows settings prefixes other than “mako.” to be used to create different factories that don’t use the global mako settings. This will be useful for the debug toolbar, which can currently be sabotaged by someone using custom mako configuration settings.
- More informative error message when a config.include cannot find an includeme. See https://github.com/Pylons/pyramid/pull/392.
- Internal: catch unhashable discriminators early (raise an error instead of allowing them to find their way into resolveConflicts).
- The match_param view predicate now accepts a string or a tuple. This replaces the broken behavior of accepting a dict. See https://github.com/Pylons/pyramid/issues/425 for more information.
- The process will now restart when pserve is used with the --reload flag when the development.ini file (or any other .ini file in use) is changed. See https://github.com/Pylons/pyramid/issues/377 and https://github.com/Pylons/pyramid/pull/411
- The prequest script would fail when used against URLs which did not return HTML or text. See https://github.com/Pylons/pyramid/issues/381
- The match_param view predicate no longer accepts a dict. This will have no negative affect because the implementation was broken for dict-based arguments.
- Add a traversal hello world example to the narrative docs.
- New API: pyramid.config.Configurator.set_request_property. Add lazy property descriptors to a request without changing the request factory. This method provides conflict detection and is the suggested way to add properties to a request.
- Responses generated by Pyramid’s static_view now use a wsgi.file_wrapper (see http://www.python.org/dev/peps/pep-0333/#optional-platform-specific-file-handling) when one is provided by the web server.
- Views registered with an accept could not be overridden correctly with a different view that had the same predicate arguments. See https://github.com/Pylons/pyramid/pull/404 for more information.
- When using a dotted name for a view argument to Configurator.add_view that pointed to a class with a view_defaults decorator, the view defaults would not be applied. See https://github.com/Pylons/pyramid/issues/396 .
- Static URL paths were URL-quoted twice. See https://github.com/Pylons/pyramid/issues/407 .
- The pyramid.view.view_defaults decorator did not work properly when more than one view relied on the defaults being different for configuration conflict resolution. See https://github.com/Pylons/pyramid/issues/394.
- The path_info route and view predicates now match against request.upath_info (Unicode) rather than request.path_info (indeterminate value based on Python 3 vs. Python 2). This has to be done to normalize matching on Python 2 and Python 3.
- New API: pyramid.request.Request.set_property. Add lazy property descriptors to a request without changing the request factory. New properties may be reified, effectively caching the value for the lifetime of the instance. Common use-cases for this would be to get a database connection for the request or identify the current user.
- Use the waitress WSGI server instead of wsgiref in scaffolding.
The documentation of pyramid.events.subscriber indicated that using it as a decorator with no arguments like this:
@subscriber() def somefunc(event): pass
Would register somefunc to receive all events sent via the registry, but this was untrue. Instead, it would receive no events at all. This has now been fixed and the code matches the documentation. See also https://github.com/Pylons/pyramid/issues/386
Literal portions of route patterns were not URL-quoted when route_url or route_path was used to generate a URL or path.
The result of route_path or route_url might have been unicode or str depending on the input. It is now guaranteed to always be str.
URL matching when the pattern contained non-ASCII characters in literal parts was indeterminate. Now the pattern supplied to add_route is assumed to be either: a unicode value, or a str value that contains only ASCII characters. If you now want to match the path info from a URL that contains high order characters, you can pass the Unicode representation of the decoded path portion in the pattern.
When using a traverse= route predicate, traversal would fail with a URLDecodeError if there were any high-order characters in the traversal pattern or in the matched dynamic segments.
Using a dynamic segment named traverse in a route pattern like this:
Would cause a UnicodeDecodeError when the route was matched and the matched portion of the URL contained any high-order characters. See https://github.com/Pylons/pyramid/issues/385 .
When using a *traverse stararg in a route pattern, a URL that matched that possessed a @@ in its name (signifying a view name) would be inappropriately quoted by the traversal machinery during traversal, resulting in the view not being found properly. See https://github.com/Pylons/pyramid/issues/382 and https://github.com/Pylons/pyramid/issues/375 .
String values passed to route_url or route_path that are meant to replace “remainder” matches will now be URL-quoted except for embedded slashes. For example:
config.add_route('remain', '/foo*remainder') request.route_path('remain', remainder='abc / def') # -> '/foo/abc%20/%20def'
Previously string values passed as remainder replacements were tacked on untouched, without any URL-quoting. But this doesn’t really work logically if the value passed is Unicode (raw unicode cannot be placed in a URL or in a path) and it is inconsistent with the rest of the URL generation machinery if the value is a string (it won’t be quoted unless by the caller).
Some folks will have been relying on the older behavior to tack on query string elements and anchor portions of the URL; sorry, you’ll need to change your code to use the _query and/or _anchor arguments to route_path or route_url to do this now.
If you pass a bytestring that contains non-ASCII characters to add_route as a pattern, it will now fail at startup time. Use Unicode instead.
- Added a prequest script (along the lines of paster request). It is documented in the “Command-Line Pyramid” chapter in the section entitled “Invoking a Request”.
- Add undocumented __discriminator__ API to derived view callables. e.g. adapters.lookup(...).__discriminator__(context, request). It will be used by superdynamic systems that require the discriminator to be used for introspection after manual view lookup.
- Normalized exit values and -h output for all p* scripts (pviews, proutes, etc).
- Added a section named “Making Your Script into a Console Script” in the “Command-Line Pyramid” chapter.
- Removed the “Running Pyramid on Google App Engine” tutorial from the main docs. It survives on in the Cookbook (http://docs.pylonsproject.org/projects/pyramid_cookbook/en/latest/gae.html). Rationale: it provides the correct info for the Python 2.5 version of GAE only, and this version of Pyramid does not support Python 2.5.
- New API: pyramid.view.view_defaults. If you use a class as a view, you can use the new view_defaults class decorator on the class to provide defaults to the view configuration information used by every @view_config decorator that decorates a method of that class. It also works against view configurations involving a class made imperatively.
- Added a backwards compatibility knob to pcreate to emulate paster create handling for the --list-templates option.
- Changed scaffolding machinery around a bit to make it easier for people who want to have extension scaffolds that can work across Pyramid 1.0.X, 1.1.X, 1.2.X and 1.3.X. See the new “Creating Pyramid Scaffolds” chapter in the narrative documentation for more info.
- Added documentation to “View Configuration” narrative documentation chapter about view_defaults class decorator.
- Added API docs for view_defaults class decorator.
- Added an API docs chapter for pyramid.scaffolds.
- Added a narrative docs chapter named “Creating Pyramid Scaffolds”.
- The template_renderer method of pyramid.scaffolds.PyramidScaffold was renamed to render_template. If you were overriding it, you’re a bad person, because it wasn’t an API before now. But we’re nice so we’re letting you know.
- Python 3.2 compatibility.
- New pyramid.compat module and API documentation which provides Python 2/3 straddling support for Pyramid add-ons and development environments.
- A mako.directories setting is no longer required to use Mako templates Rationale: Mako template renderers can be specified using an absolute asset spec. An entire application can be written with such asset specs, requiring no ordered lookup path.
- bpython interpreter compatibility in pshell. See the “Command-Line Pyramid” narrative docs chapter for more information.
- Added get_appsettings API function to the pyramid.paster module. This function returns the settings defined within an [app:...] section in a PasteDeploy ini file.
- Added setup_logging API function to the pyramid.paster module. This function sets up Python logging according to the logging configuration in a PasteDeploy ini file.
- Configuration conflict reporting is reported in a more understandable way (“Line 11 in file…” vs. a repr of a tuple of similar info).
- A configuration introspection system was added; see the narrative documentation chapter entitled “Pyramid Configuration Introspection” for more information. New APIs: pyramid.registry.Introspectable, pyramid.config.Configurator.introspector, pyramid.config.Configurator.introspectable, pyramid.registry.Registry.introspector.
- Allow extra keyword arguments to be passed to the pyramid.config.Configurator.action method.
- New APIs: pyramid.path.AssetResolver and pyramid.path.DottedNameResolver. The former can be used to resolve asset specifications, the latter can be used to resolve dotted names to modules or packages.
- Make test suite pass on 32-bit systems; closes #286. closes #306. See also https://github.com/Pylons/pyramid/issues/286
- The pryamid.view.view_config decorator did not accept a match_params predicate argument. See https://github.com/Pylons/pyramid/pull/308
- The AuthTktCookieHelper could potentially generate Unicode headers inappropriately when the tokens argument to remember was used. See https://github.com/Pylons/pyramid/pull/314.
- The AuthTktAuthenticationPolicy did not use a timing-attack-aware string comparator. See https://github.com/Pylons/pyramid/pull/320 for more info.
- The DummySession in pyramid.testing now generates a new CSRF token if one doesn’t yet exist.
- request.static_url now generates URL-quoted URLs when fed a path argument which contains characters that are unsuitable for URLs. See https://github.com/Pylons/pyramid/issues/349 for more info.
- Prevent a scaffold rendering from being named site (conflicts with Python internal site.py).
- Support for using instances as targets of the pyramid.wsgi.wsgiapp and pryramid.wsgi.wsgiapp2 functions. See https://github.com/Pylons/pyramid/pull/370 for more info.
- Pyramid no longer runs on Python 2.5 (which includes the most recent release of Jython and the Python 2.5 version of GAE as of this writing).
- The paster command is no longer the documented way to create projects, start the server, or run debugging commands. To create projects from scaffolds, paster create is replaced by the pcreate console script. To serve up a project, paster serve is replaced by the pserve console script. New console scripts named pshell, pviews, proutes, and ptweens do what their paster <commandname> equivalents used to do. Rationale: the Paste and PasteScript packages do not run under Python 3.
- The default WSGI server run as the result of pserve from newly rendered scaffolding is now the wsgiref WSGI server instead of the paste.httpserver server. Rationale: Rationale: the Paste and PasteScript packages do not run under Python 3.
- The pshell command (see “paster pshell”) no longer accepts a --disable-ipython command-line argument. Instead, it accepts a -p or --python-shell argument, which can be any of the values python, ipython or bpython.
- Removed the pyramid.renderers.renderer_from_name function. It has been deprecated since Pyramid 1.0, and was never an API.
- To use ZCML with versions of Pyramid >= 1.3, you will need pyramid_zcml version >= 0.8 and zope.configuration version >= 3.8.0. The pyramid_zcml package version 0.8 is backwards compatible all the way to Pyramid 1.0, so you won’t be warned if you have older versions installed and upgrade Pyramid “in-place”; it may simply break instead.
- Pyramid no longer depends on the zope.component package, except as a testing dependency.
- Pyramid now depends on a zope.interface>=3.8.0, WebOb>=1.2dev, repoze.lru>=0.4, zope.deprecation>=3.5.0, translationstring>=0.4 (for Python 3 compatibility purposes). It also, as a testing dependency, depends on WebTest>=1.3.1 for the same reason.
- Pyramid no longer depends on the Paste or PasteScript packages.
- The SQLAlchemy Wiki tutorial has been updated. It now uses @view_config decorators and an explicit database population script.
- Minor updates to the ZODB Wiki tutorial.
- A narrative documentation chapter named “Extending Pyramid Configuration” was added; it describes how to add a new directive, and how use the pyramid.config.Configurator.action method within custom directives. It also describes how to add introspectable objects.
- A narrative documentation chapter named “Pyramid Configuration Introspection” was added. It describes how to query the introspection system.
- Rendered scaffolds have now been changed to be more relocatable (fewer mentions of the package name within files in the package).
- The routesalchemy scaffold has been renamed alchemy, replacing the older (traversal-based) alchemy scaffold (which has been retired).
- The starter scaffold now uses URL dispatch by default.