Streaming

Since b0a1571ff61a , Piston supports streaming its output to the client. This is disabled per default, for one reason:

• Django’s support for streaming breaks with ConditionalGetMiddleware and CommonMiddleware.

To get around this, Piston ships with two “proxy middleware classes” that won’t execute during a streaming scenario, and hence won’t look at (and exhaust) the data before sending it to the client. Without these, Django will look at the contents (to figure out E-Tags and Content-Length), and by doing so, the next peek it takes, will result in nothing.

In piston.middleware there are two classes you can effectively replace these with.

In settings.py:

MIDDLEWARE_CLASSES = (
   # ...
    'piston.middleware.ConditionalMiddlewareCompatProxy',
    'piston.middleware.CommonMiddlewareCompatProxy',
   # ...
)

Remove any mentions of ConditionalGetMiddleware and CommonMiddleware, or it won’t work. If you have any other middleware that looks at the content prior to streaming, you can wrap those in the conditional middleware proxy too:

from piston.middleware import compat_middleware_factory

class MyMiddleware(...):
   ...

MyMiddlewareCompatProxy = compat_middleware_factory(MyMiddleware)

And then install MyMiddlewareCompatProxy instead.