.. index:: single: environment variables single: settings single: reload single: debug_authorization single: reload_assets single: debug_notfound single: debug_all single: reload_all single: debug settings single: reload settings single: default_locale_name single: environment variables single: ini file settings single: PasteDeploy settings .. _environment_chapter: Environment Variables and ``.ini`` File Settings ================================================ :app:`Pyramid` behavior can be configured through a combination of operating system environment variables and ``.ini`` configuration file application section settings. The meaning of the environment variables and the configuration file settings overlap. .. note:: Where a configuration file setting exists with the same meaning as an environment variable, and both are present at application startup time, the environment variable setting takes precedence. The term "configuration file setting name" refers to a key in the ``.ini`` configuration for your application. The configuration file setting names documented in this chapter are reserved for :app:`Pyramid` use. You should not use them to indicate application-specific configuration settings. Reloading Templates ------------------- When this value is true, templates are automatically reloaded whenever they are modified without restarting the application, so you can see changes to templates take effect immediately during development. This flag is meaningful to Chameleon and Mako templates, as well as most third-party template rendering extensions. +---------------------------------+-----------------------------+ | Environment Variable Name | Config File Setting Name | +=================================+=============================+ | ``PYRAMID_RELOAD_TEMPLATES`` | ``reload_templates`` | | | | | | | | | | +---------------------------------+-----------------------------+ Reloading Assets ---------------- Don't cache any asset file data when this value is true. See also :ref:`overriding_assets_section`. +---------------------------------+-----------------------------+ | Environment Variable Name | Config File Setting Name | +=================================+=============================+ | ``PYRAMID_RELOAD_ASSETS`` | ``reload_assets`` | | | | | | | | | | +---------------------------------+-----------------------------+ .. note:: For backwards compatibility purposes, aliases can be used for configurating asset reloading: ``PYRAMID_RELOAD_RESOURCES`` (envvar) and ``reload_resources`` (config file). Debugging Authorization ----------------------- Print view authorization failure and success information to stderr when this value is true. See also :ref:`debug_authorization_section`. +---------------------------------+-----------------------------+ | Environment Variable Name | Config File Setting Name | +=================================+=============================+ | ``PYRAMID_DEBUG_AUTHORIZATION`` | ``debug_authorization`` | | | | | | | | | | +---------------------------------+-----------------------------+ Debugging Not Found Errors -------------------------- Print view-related ``NotFound`` debug messages to stderr when this value is true. See also :ref:`debug_notfound_section`. +---------------------------------+-----------------------------+ | Environment Variable Name | Config File Setting Name | +=================================+=============================+ | ``PYRAMID_DEBUG_NOTFOUND`` | ``debug_notfound`` | | | | | | | | | | +---------------------------------+-----------------------------+ Debugging Route Matching ------------------------ Print debugging messages related to :term:`url dispatch` route matching when this value is true. See also :ref:`debug_routematch_section`. +---------------------------------+-----------------------------+ | Environment Variable Name | Config File Setting Name | +=================================+=============================+ | ``PYRAMID_DEBUG_ROUTEMATCH`` | ``debug_routematch`` | | | | | | | | | | +---------------------------------+-----------------------------+ Debugging All ------------- Turns on all ``debug*`` settings. +---------------------------------+-----------------------------+ | Environment Variable Name | Config File Setting Name | +=================================+=============================+ | ``PYRAMID_DEBUG_ALL`` | ``debug_all`` | | | | | | | | | | +---------------------------------+-----------------------------+ Reloading All ------------- Turns on all ``reload*`` settings. +---------------------------------+-----------------------------+ | Environment Variable Name | Config File Setting Name | +=================================+=============================+ | ``PYRAMID_RELOAD_ALL`` | ``reload_all`` | | | | | | | | | | +---------------------------------+-----------------------------+ .. _default_locale_name_setting: Default Locale Name -------------------- The value supplied here is used as the default locale name when a :term:`locale negotiator` is not registered. See also :ref:`localization_deployment_settings`. +---------------------------------+-----------------------------+ | Environment Variable Name | Config File Setting Name | +=================================+=============================+ | ``PYRAMID_DEFAULT_LOCALE_NAME`` | ``default_locale_name`` | | | | | | | | | | +---------------------------------+-----------------------------+ .. _mako_template_renderer_settings: Mako Template Render Settings ----------------------------- Mako derives additional settings to configure its template renderer that should be set when using it. Many of these settings are optional and only need to be set if they should be different from the default. The Mako Template Renderer uses a subclass of Mako's `template lookup `_ and accepts several arguments to configure it. Mako Directories ++++++++++++++++ The value(s) supplied here are passed in as the template directories. They should be in :term:`asset specification` format, for example: ``my.package:templates``. +-----------------------------+ | Config File Setting Name | +=============================+ | ``mako.directories`` | | | | | | | +-----------------------------+ Mako Module Directory +++++++++++++++++++++ The value supplied here tells Mako where to store compiled Mako templates. If omitted, compiled templates will be stored in memory. This value should be an absolute path, for example: ``%(here)s/data/templates`` would use a directory called ``data/templates`` in the same parent directory as the INI file. +-----------------------------+ | Config File Setting Name | +=============================+ | ``mako.module_directory`` | | | | | | | +-----------------------------+ Mako Input Encoding +++++++++++++++++++ The encoding that Mako templates are assumed to have. By default this is set to ``utf-8``. If you wish to use a different template encoding, this value should be changed accordingly. +-----------------------------+ | Config File Setting Name | +=============================+ | ``mako.input_encoding`` | | | | | | | +-----------------------------+ Mako Error Handler ++++++++++++++++++ Python callable which is called whenever Mako compile or runtime exceptions occur. The callable is passed the current context as well as the exception. If the callable returns True, the exception is considered to be handled, else it is re-raised after the function completes. Is used to provide custom error-rendering functions. +-----------------------------+ | Config File Setting Name | +=============================+ | ``mako.error_handler`` | | | | | | | +-----------------------------+ Mako Default Filters ++++++++++++++++++++ List of string filter names that will be applied to all Mako expressions. +-----------------------------+ | Config File Setting Name | +=============================+ | ``mako.default_filters`` | | | | | | | +-----------------------------+ Mako Import +++++++++++ String list of Python statements, typically individual “import” lines, which will be placed into the module level preamble of all generated Python modules. +-----------------------------+ | Config File Setting Name | +=============================+ | ``mako.imports`` | | | | | | | +-----------------------------+ Mako Strict Undefined +++++++++++++++++++++ ``true`` or ``false``, representing the "strict undefined" behavior of Mako (see `Mako Context Variables `_). By default, this is ``false``. +-----------------------------+ | Config File Setting Name | +=============================+ | ``mako.strict_undefined`` | | | | | | | +-----------------------------+ Examples -------- Let's presume your configuration file is named ``MyProject.ini``, and there is a section representing your application named ``[app:main]`` within the file that represents your :app:`Pyramid` application. The configuration file settings documented in the above "Config File Setting Name" column would go in the ``[app:main]`` section. Here's an example of such a section: .. code-block:: ini :linenos: [app:main] use = egg:MyProject#app reload_templates = true debug_authorization = true You can also use environment variables to accomplish the same purpose for settings documented as such. For example, you might start your :app:`Pyramid` application using the following command line: .. code-block:: text $ PYRAMID_DEBUG_AUTHORIZATION=1 PYRAMID_RELOAD_TEMPLATES=1 \ bin/paster serve MyProject.ini If you started your application this way, your :app:`Pyramid` application would behave in the same manner as if you had placed the respective settings in the ``[app:main]`` section of your application's ``.ini`` file. If you want to turn all ``debug`` settings (every setting that starts with ``debug_``). on in one fell swoop, you can use ``PYRAMID_DEBUG_ALL=1`` as an environment variable setting or you may use ``debug_all=true`` in the config file. Note that this does not affect settings that do not start with ``debug_*`` such as ``reload_templates``. If you want to turn all ``reload`` settings (every setting that starts with ``reload_``). on in one fell swoop, you can use ``PYRAMID_RELOAD_ALL=1`` as an environment variable setting or you may use ``reload_all=true`` in the config file. Note that this does not affect settings that do not start with ``reload_*`` such as ``debug_notfound``. .. note:: Specifying configuration settings via environment variables is generally most useful during development, where you may wish to augment or override the more permanent settings in the configuration file. This is useful because many of the reload and debug settings may have performance or security (i.e., disclosure) implications that make them undesirable in a production environment. .. index:: single: reload_templates single: reload_assets Understanding the Distinction Between ``reload_templates`` and ``reload_assets`` -------------------------------------------------------------------------------- The difference between ``reload_assets`` and ``reload_templates`` is a bit subtle. Templates are themselves also treated by :app:`Pyramid` as asset files (along with other static files), so the distinction can be confusing. It's helpful to read :ref:`overriding_assets_section` for some context about assets in general. When ``reload_templates`` is true, :app:`Pyramid` takes advantage of the underlying templating systems' ability to check for file modifications to an individual template file. When ``reload_templates`` is true but ``reload_assets`` is *not* true, the template filename returned by the ``pkg_resources`` package (used under the hood by asset resolution) is cached by :app:`Pyramid` on the first request. Subsequent requests for the same template file will return a cached template filename. The underlying templating system checks for modifications to this particular file for every request. Setting ``reload_templates`` to ``True`` doesn't affect performance dramatically (although it should still not be used in production because it has some effect). However, when ``reload_assets`` is true, :app:`Pyramid` will not cache the template filename, meaning you can see the effect of changing the content of an overridden asset directory for templates without restarting the server after every change. Subsequent requests for the same template file may return different filenames based on the current state of overridden asset directories. Setting ``reload_assets`` to ``True`` affects performance *dramatically*, slowing things down by an order of magnitude for each template rendering. However, it's convenient to enable when moving files around in overridden asset directories. ``reload_assets`` makes the system *very slow* when templates are in use. Never set ``reload_assets`` to ``True`` on a production system.