A.2.1.7 Session Changes
Keywords: albatross

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A.2.1.7 Session Changes

The `Application.run()` method now saves the session before flushing the response to the browser. This allows applications to support dynamically generated images.

The `SessionBase.add_session_vars()` method now raises an `ApplicationError` exception if you attempt to add variables to the session which do not exist in the local namespace.

The `SessionBase.default_session_var()` method allows you to add a variable to the session and place it in the local namespace at the same time.

Session saving previously silently removed session values which could not be pickled. Now unpickleable values are reported via an `ApplicationError` exception.

Errors handling and reporting during session loading has been improved.