This seems to be required only when calling render :partial with an
empty collection from a controller. This call happens to return no
content, letting the response body empty, which means to Rails that it
should go on and try to find a template to render based on the current
action name, thus failing hard.
Although tests keep all green, we need to check a better way to fix
this.
This is because only template rendering works with streaming.
Setting it at the class level was also changing the behavior
of JSON and XML responses, closes#1337.
* Add the Rack::Sendfile middleware
* Make the header to use configurable via config.action_dispatch.x_sendfile_header (default to "X-Sendfile").
* Add Railties tests to confirm that these work
* Remove the :stream, :buffer_size, and :x_senfile default options to send_file
* Change the log subscriber to always say "Sent file"
* Add deprecation warnings for options that are now no-ops
Note that servers can configure this by setting X-Sendfile-Type. Hosting companies and those creating packages of servers specially designed for Rails applications are encouraged to specify this header so that this can work transparently.
* Tentatively replaced HeaderHash with SimpleHeaderHash, which does not preserve
case but does handle converting Arrays to Strings in to_hash. This requires
further discussion.
* Moved default_charset to ActionDispatch::Response to avoid having to hop over
to ActionController. Ideally, this would be a constant on AD::Response, but
some tests expect to be able to change it dynamically and I didn't want to change
them yet.
* Completely override #initialize from Rack::Response. Previously, it was creating
a HeaderHash, and then we were creating an entirely new one. There is no way to
call super without incurring the overhead of creating a HeaderHash.
* Override #write from Rack::Response. Its implementation tracks Content-Length,
and doing so adds additional overhead that could be mooted if other middleware
changes the body. It is more efficiently done at the top-level server.
* Change sending_file to an instance_variable instead of header inspection. In
general, if a state is important, it should be set as a property of the response
not reconstructed later.
* Set the Etag to @body instead of .body. AS::Cache.expand_cache_key handles
Arrays fine, and it's more efficient to let it handle the body parts, since
it is not forced to create a joined String.
* If we detect the default cache control case, just set it, rather than setting
the constituent parts and then running the normal (expensive) code to generate
the string.
