#

# copyright (c) 2004-2007, cherrypy team ([email protected])

# all rights reserved.

#

# redistribution and use in source and binary forms, with or without modification,

# are permitted provided that the following conditions are met:

#

#     * redistributions of source code must retain the above copyright notice,

#       this list of conditions and the following disclaimer.

#     * redistributions in binary form must reproduce the above copyright notice,

#       this list of conditions and the following disclaimer in the documentation

#       and/or other materials provided with the distribution.

#     * neither the name of the cherrypy team nor the names of its contributors

#       may be used to endorse or promote products derived from this software

#       without specific prior written permission.

#

# this software is provided by the copyright holders and contributors "as is" and

# any express or implied warranties, including, but not limited to, the implied

# warranties of merchantability and fitness for a particular purpose are

# disclaimed. in no event shall the copyright owner or contributors be liable

# for any direct, indirect, incidental, special, exemplary, or consequential

# damages (including, but not limited to, procurement of substitute goods or

# services; loss of use, data, or profits; or business interruption) however

# caused and on any theory of liability, whether in contract, strict liability,

# or tort (including negligence or otherwise) arising in any way out of the use

# of this software, even if advised of the possibility of such damage.

#

#

# Copyright 2009 Sun Microsystems, Inc.  All rights reserved.

# Use is subject to license terms.

#

import sys as _sys

import cherrypy as _cherrypy

from cherrypy import _cperror

from cherrypy import _cpwsgi

class DepotResponse(_cpwsgi.AppResponse):

        """ This class is a partial combination of a cherrypy's original

            AppResponse class with a change to "Stage 2" of setapp to provide

            access to the write() callable specified by PEP 333.  Access to this

            callable is necessary to maintain a minimal memory and disk

            footprint for streaming operations performed by the depot server,

            such as filelist. """

        def __add_write_hook(self, s, h, exc):

                # The WSGI specification includes a special write()

                # callable returned by the start_response callable.

                # cherrypy traditionally hides this from applications

                # as new WSGI applications and frameworks are not

                # supposed to use it if at all possible.  The write()

                # callable is considered a hack to support imperative

                # streaming APIs.

                #

                # As a result, we have to provide access to the write()

                # callable ourselves by replacing the default

                # response_class with our own.  This callable is

                # provided so that streaming APIs can be treated as if

                # their output had been yielded by an iterable.

                #

                # The cherrypy singleton below is thread-local, and

                # guaranteed to only be set for a specific request.

                # This means any callables that use the singleton

                # to access this method are guaranteed to write output

                # back to the same request.

                #

                # See: http://www.python.org/dev/peps/pep-0333/

                #

                _cherrypy.response.write = self.start_response(s, h, exc)

        def setapp(self):

                try:

                        self.request = self.get_request()

                        s, h, b = self.get_response()

                        self.iter_response = iter(b)

                        self.__add_write_hook(s, h, None)

                except self.throws:

                        self.close()

                        raise

                except _cherrypy.InternalRedirect, ir:

                        self.environ['cherrypy.previous_request'] = _cherrypy.serving.request

                        self.close()

                        self.iredirect(ir.path, ir.query_string)

                        return

                except:

                        if getattr(self.request, "throw_errors", False):

                                self.close()

                                raise

                        tb = _cperror.format_exc()

                        _cherrypy.log(tb, severity=40)

                        if not getattr(self.request, "show_tracebacks", True):

                                tb = ""

                        s, h, b = _cperror.bare_error(tb)

                        self.iter_response = iter(b)

                        try:

                                self.__add_write_hook(s, h, _sys.exc_info())

                        except:

                                # "The application must not trap any exceptions raised by

                                # start_response, if it called start_response with exc_info.

                                # Instead, it should allow such exceptions to propagate

                                # back to the server or gateway."

                                # But we still log and call close() to clean up ourselves.

                                _cherrypy.log(traceback=True, severity=40)

                                self.close()

                                raise