def body
str = ''
each { |part| str << part.to_s }
str
end
This is problematic in instances where a streaming body is used, due
to the definition of Rack::Response#close:
def close
body.close if body.respond_to?(:close)
end
Given these definitions, executing the Rack protocol on an
ActionDispatch::Response instance (calling '#each', then '#close')
causes the body to be enumerated twice -- once via the expected call
to #each, and a second time via the call chain #close -> #body ->
#each. See https://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/4554
for a user report of this problem.
This could be fixed by using the instance variable directly:
def close
@body.close if @body.respond_to?(:close)
end
However, I think ActionDispatch::Response's #body override is
dangerous and violates the principle of least surprise by removing the
symmetry between #body and #body=. IMHO, it would be better to remove
the override. If the concatenating behavior is necessary, supply a
method named #body_text or a similar name that makes it clear that it
disables streaming. This option causes numerous Rails test failures,
however, as many tests are written to expect #body to return a string.
Thoughts?
Konstantin
I agree that would fix this particular issue. My reluctance with that
is that AD::Response#body would remain a dangerous method on its own,
because it does not obey the semantics established by the base class.
It's a Liskov Substitution Principle violation -- AD::Response cannot
be safely substituted where Rack::Response is expected.