Pyramid

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Pyramid is a small, fast, down-to-earth, open source Python web framework. It makes real-world web application development and deployment more fun, more predictable, and more productive. Try Pyramid <https://trypyramid.com/>_, browse its add-ons and documentation, and get an overview.

.. code-block:: python

from wsgiref.simple_server import make_server
from pyramid.config import Configurator
from pyramid.response import Response

def hello_world(request):
    return Response('Hello World!')

if __name__ == '__main__':
    with Configurator() as config:
        config.add_route('hello', '/')
        config.add_view(hello_world, route_name='hello')
        app = config.make_wsgi_app()
    server = make_server('0.0.0.0', 6543, app)
    server.serve_forever()

Pyramid is a project of the Pylons Project <https://pylonsproject.org>_.

Support and Documentation

See Pyramid Support and Development <https://docs.pylonsproject.org/projects/pyramid/en/latest/#support-and-development>_ for documentation, reporting bugs, and getting support.

Developing and Contributing

See HACKING.txt <https://github.com/Pylons/pyramid/blob/main/HACKING.txt>_ and contributing.md <https://github.com/Pylons/pyramid/blob/main/contributing.md>_ for guidelines on running tests, adding features, coding style, and updating documentation when developing in or contributing to Pyramid.

License

Pyramid is offered under the BSD-derived Repoze Public License <http://repoze.org/license.html>_.

Authors

Pyramid is made available by Agendaless Consulting <https://agendaless.com>_ and a team of contributors <https://github.com/Pylons/pyramid/graphs/contributors>_.

.. _changes_2.0.2:

2.0.2 (2023-08-25)

Bug Fixes

• Removed support for null-bytes in the path when making a request for a file against a static_view. Whille null-bytes are allowed by the HTTP specification, due to the handling of null-bytes potentially leading to security vulnerabilities it is no longer supported.

  This fixes a security vulnerability that is present due to a bug in Python 3.11.0 through 3.11.4, thereby allowing the unintended disclosure of an index.html one directory up from the static views path.

  Thanks to Masashi Yamane of LAC Co., Ltd for reporting this issue.

Backward Incompatibilities

• Requests to a static_view are no longer allowed to contain a null-byte in any part of the path segment.

.. _changes_2.0.1:

2.0.1 (2023-01-29)

• Add support for Python 3.10 and 3.11.

• Copy __name__ from decorated attribute when using pyramid.decorator.reify. See https://github.com/Pylons/pyramid/pull/3660

• Fix method signatures in docs for pyramid.config.Configurator.add_static_view and pyramid.config.Configurator.override_asset. See https://github.com/Pylons/pyramid/pull/3699

• Remove obsolete stackframe hack used in Python 3.5.0 when showing configurator conflict errors. See https://github.com/Pylons/pyramid/pull/3700

• Fix an error when injecting certain objects into the pshell env due to the use of !=. See https://github.com/Pylons/pyramid/pull/3704

• Pyramid drops support for l*gettext() methods in the i18n module. These have been deprecated in Python's gettext module since 3.8, and removed in Python 3.11. They also shouldn't be used at all on Python 3. See https://github.com/Pylons/pyramid/pull/3717

• Avoid setDaemon(True) deprecation warning by updating threading API usage to .daemon = True.

2.0 (2021-02-28)

• No changes from 2.0b1.

2.0b1 (2021-02-20)

• Break potential reference cycle between request and context. See https://github.com/Pylons/pyramid/pull/3649

• Remove update_wrapper from pyramid.decorator.reify. See https://github.com/Pylons/pyramid/pull/3657

2.0b0 (2020-12-15)

• Overhaul tutorials and update cookiecutter to de-emphasize request.user in favor of request.identity for common use cases. See https://github.com/Pylons/pyramid/pull/3629

• Improve documentation and patterns with builtin fixtures shipped in the cookiecutters. See https://github.com/Pylons/pyramid/pull/3629

2.0a0 (2020-11-29)

Features

• Add support for Python 3.9. See https://github.com/Pylons/pyramid/issues/3622

• The aslist method now handles non-string objects when flattening. See https://github.com/Pylons/pyramid/pull/3594

• It is now possible to pass multiple values to the header predicate for route and view configuration. See https://github.com/Pylons/pyramid/pull/3576

• Add support for Python 3.8. See https://github.com/Pylons/pyramid/pull/3547

• New security APIs have been added to support a massive overhaul of the authentication and authorization system. Read "Upgrading Authentication/Authorization" in the "What's New in Pyramid 2.0" chapter of the documentation for information about using this new system.

  • pyramid.config.Configurator.set_security_policy.
  • pyramid.interfaces.ISecurityPolicy
  • pyramid.request.Request.identity.
  • pyramid.request.Request.is_authenticated
  • pyramid.authentication.SessionAuthenticationHelper
  • pyramid.authorization.ACLHelper
  • is_authenticated=True/False predicate for route and view configs

  See https://github.com/Pylons/pyramid/pull/3465 and https://github.com/Pylons/pyramid/pull/3598

• Changed the default serializer on pyramid.session.SignedCookieSessionFactory to use pyramid.session.JSONSerializer instead of pyramid.session.PickleSerializer. Read "Upgrading Session Serialization" in the "What's New in Pyramid 2.0" chapter of the documentation for more information about why this change was made. See https://github.com/Pylons/pyramid/pull/3413

• It is now possible to control whether a route pattern contains a trailing slash when it is composed with a route prefix using config.include(..., route_prefix=...) or with config.route_prefix_context(...). This can be done by specifying an empty pattern and setting the new argument inherit_slash=True. For example:

  .. code-block:: python

  with config.route_prefix_context('/users'):
      config.add_route('users', '', inherit_slash=True)
  

  In the example, the resulting pattern will be /users. Similarly, if the route prefix were /users/ then the final pattern would be /users/. If the pattern was '/', then the final pattern would always be /users/. This new setting is only available if the pattern supplied to add_route is the empty string (''). See https://github.com/Pylons/pyramid/pull/3420

• No longer define pyramid.request.Request.json_body which is already provided by WebOb. This allows the attribute to now be settable. See https://github.com/Pylons/pyramid/pull/3447

• Improve debugging info from pyramid.view.view_config decorator. See https://github.com/Pylons/pyramid/pull/3483

• A new parameter, allow_no_origin, was added to pyramid.config.Configurator.set_default_csrf_options as well as pyramid.csrf.check_csrf_origin. This option controls whether a request is rejected if it has no Origin or Referer header - often the result of a user configuring their browser not to send a Referer header for privacy reasons even on same-domain requests. The default is to reject requests without a known origin. It is also possible to allow the special Origin: null header by adding it to the pyramid.csrf_trusted_origins list in the settings. See https://github.com/Pylons/pyramid/pull/3512 and https://github.com/Pylons/pyramid/pull/3518

• A new parameter, check_origin, was added to pyramid.config.Configurator.set_default_csrf_options which disables origin checking entirely. See https://github.com/Pylons/pyramid/pull/3518

• Added pyramid.interfaces.IPredicateInfo which defines the object passed to predicate factories as their second argument. See https://github.com/Pylons/pyramid/pull/3514

• Added support for serving pre-compressed static assets by using the content_encodings argument of pyramid.config.Configurator.add_static_view and pyramid.static.static_view. See https://github.com/Pylons/pyramid/pull/3537

• Fix DeprecationWarning emitted by using the imp module. See https://github.com/Pylons/pyramid/pull/3553

• Properties created via config.add_request_method(..., property=True) or request.set_property used to be readonly. They can now be overridden via request.foo = ... and until the value is deleted it will return the overridden value. This is most useful when mocking request properties in testing. See https://github.com/Pylons/pyramid/pull/3559

• Finished callbacks are now executed as part of the closer that is invoked as part of pyramid.scripting.prepare and pyramid.paster.bootstrap. See https://github.com/Pylons/pyramid/pull/3561

• Added pyramid.request.RequestLocalCache which can be used to create simple objects that are shared across requests and can be used to store per-request data. This is useful when the source of data is external to the request itself. Often a reified property is used on a request via pyramid.config.Configurator.add_request_method, or pyramid.decorator.reify, and these work great when the data is generated on-demand when accessing the request property. However, often the case is that the data is generated when accessing some other system and then we want to cache the data for the duration of the request. See https://github.com/Pylons/pyramid/pull/3561

• Exposed pyramid.authorization.ALL_PERMISSIONS and pyramid.authorization.DENY_ALL such that all of the ACL-related constants are now importable from the pyramid.authorization namespace. See https://github.com/Pylons/pyramid/pull/3563

• pserve now outputs verbose messaging to stderr instead of stdout to circumvent buffering issues that exist by default on stdout. See https://github.com/Pylons/pyramid/pull/3593

Deprecations

• Deprecated the authentication and authorization interfaces and principal-based support. See "Upgrading Authentication/Authorization" in the "What's New in Pyramid 2.0" chapter of the documentation for information on equivalent APIs and notes on upgrading. The following APIs are deprecated as a result of this change:

  • pyramid.config.Configurator.set_authentication_policy
  • pyramid.config.Configurator.set_authorization_policy
  • pyramid.interfaces.IAuthenticationPolicy
  • pyramid.interfaces.IAuthorizationPolicy
  • pyramid.request.Request.effective_principals
  • pyramid.request.Request.unauthenticated_userid
  • pyramid.authentication.AuthTktAuthenticationPolicy
  • pyramid.authentication.RemoteUserAuthenticationPolicy
  • pyramid.authentication.RepozeWho1AuthenticationPolicy
  • pyramid.authentication.SessionAuthenticationPolicy
  • pyramid.authentication.BasicAuthAuthenticationPolicy
  • pyramid.authorization.ACLAuthorizationPolicy
  • The effective_principals view and route predicates.

  See https://github.com/Pylons/pyramid/pull/3465

• Deprecated pyramid.security.principals_allowed_by_permission. This method continues to work with the deprecated pyramid.interfaces.IAuthorizationPolicy interface but will not work with the new pyramid.interfaces.ISecurityPolicy. See https://github.com/Pylons/pyramid/pull/3465

• Deprecated several ACL-related aspects of pyramid.security. Equivalent objects should now be imported from the pyramid.authorization namespace. This includes:

  • pyramid.security.Everyone
  • pyramid.security.Authenticated
  • pyramid.security.ALL_PERMISSIONS
  • pyramid.security.DENY_ALL
  • pyramid.security.ACLAllowed
  • pyramid.security.ACLDenied

  See https://github.com/Pylons/pyramid/pull/3563

• Deprecated pyramid.session.PickleSerializer. See https://github.com/pylons/pyramid/issues/2709, and https://github.com/pylons/pyramid/pull/3353, and https://github.com/pylons/pyramid/pull/3413

Backward Incompatibilities

• Drop support for Python 2.7, 3.4, and 3.5. See https://github.com/Pylons/pyramid/pull/3421, and https://github.com/Pylons/pyramid/pull/3547, and https://github.com/Pylons/pyramid/pull/3634

• Removed the pyramid.compat module. Integrators should use the six module or vendor shims they are using into their own codebases going forward. https://github.com/Pylons/pyramid/pull/3421

• pcreate and the builtin scaffolds have been removed in favor of using the cookiecutter tool and the pyramid-cookiecutter-starter cookiecutter. The script and scaffolds were deprecated in Pyramid 1.8. See https://github.com/Pylons/pyramid/pull/3406

• Changed the default hashalg on pyramid.authentication.AuthTktCookieHelper to sha512. See https://github.com/Pylons/pyramid/pull/3557

• Removed pyramid.interfaces.ITemplateRenderer. This interface was deprecated since Pyramid 1.5 and was an interface used by libraries like pyramid_mako and pyramid_chameleon but provided no functionality within Pyramid itself. See https://github.com/Pylons/pyramid/pull/3409

• Removed pyramid.security.has_permission, pyramid.security.authenticated_userid, pyramid.security.unauthenticated_userid, and pyramid.security.effective_principals. These methods were deprecated in Pyramid 1.5 and all have equivalents available as properties on the request. For example, request.authenticated_userid. See https://github.com/Pylons/pyramid/pull/3410

• Removed support for supplying a media range to the accept predicate of both pyramid.config.Configurator.add_view and pyramid.config.Configurator.add_route. These options were deprecated in Pyramid 1.10 and WebOb 1.8 because they resulted in uncontrollable matching that was not compliant with the RFC. See https://github.com/Pylons/pyramid/pull/3411

• Removed pyramid.session.UnencryptedCookieSessionFactoryConfig. This session factory was replaced with pyramid.session.SignedCookieSessionFactory in Pyramid 1.5 and has been deprecated since then. See https://github.com/Pylons/pyramid/pull/3412

• Removed pyramid.session.signed_serialize, and pyramid.session.signed_deserialize. These methods were only used by the now-removed pyramid.session.UnencryptedCookieSessionFactoryConfig and were coupled to the vulnerable pickle serialization format which could lead to remove code execution if the secret key is compromised. See https://github.com/Pylons/pyramid/pull/3412

• Changed the default serializer on pyramid.session.SignedCookieSessionFactory to use pyramid.session.JSONSerializer instead of pyramid.session.PickleSerializer. Read "Upgrading Session Serialization" in the "What's New in Pyramid 2.0" chapter of the documentation for more information about why this change was made. See https://github.com/Pylons/pyramid/pull/3413

• pyramid.request.Request.invoke_exception_view will no longer be called by the default execution policy. See https://github.com/Pylons/pyramid/pull/3496

• pyramid.config.Configurator.scan will no longer, by default, execute Venusian decorator callbacks registered for categories other than 'pyramid'. To find any decorator regardless of category, specify config.scan(..., categories=None). See https://github.com/Pylons/pyramid/pull/3510

• The second argument to predicate factories has been changed from config to info, an instance of pyramid.interfaces.IPredicateInfo. This limits the data available to predicates but still provides the package, registry, settings and dotted-name resolver which should cover most use cases and is largely backward compatible. See https://github.com/Pylons/pyramid/pull/3514

• Removed the check_csrf predicate. Instead, use pyramid.config.Configurator.set_default_csrf_options and the require_csrf view option to enable automatic CSRF checking. See https://github.com/Pylons/pyramid/pull/3521

• Update the default behavior of pyramid.authenticationAuthTktAuthenticationPolicy and pyramid.authentication.AuthTktCookieHelper to only set a single cookie without a domain parameter when no other domain constraints are specified. Prior to this change, wild_domain=False (the default) was effectively treated the same as wild_domain=True, in which a cookie was defined such that browsers would use it both for the request's domain, as well as any subdomain. In the new behavior, cookies will only affect the current domain, and not subdomains, by default. See https://github.com/Pylons/pyramid/pull/3587

Documentation Changes

• Restore build of PDF on Read The Docs. See https://github.com/Pylons/pyramid/issues/3290

• Fix docs build for Sphinx 2.0. See https://github.com/Pylons/pyramid/pull/3480

• Significant updates to the wiki, wiki2 tutorials to demonstrate the new security policy usage as well as a much more production-ready test harness. See https://github.com/Pylons/pyramid/pull/3557