etwist/http.py
author Sylvain Thénault <sylvain.thenault@logilab.fr>
Thu, 20 May 2010 20:47:55 +0200
changeset 5556 9ab2b4c74baf
parent 5513 07b32d9d8804
child 7855 54283a5b7afc
permissions -rw-r--r--
[entity] introduce a new 'adapters' registry This changeset introduces the notion in adapters (as in Zope Component Architecture) in a cubicweb way, eg using a specific registry of appobjects. This allows nicer code structure, by avoid clutering entity classes and moving code usually specific to a place of the ui (or something else) together with the code that use the interface. We don't use actual interface anymore, they are implied by adapters (which may be abstract), whose reg id is an interface name. Appobjects that used to 'implements(IFace)' should now be rewritten by: * coding an IFaceAdapter(EntityAdapter) defining (implementing if desired) the interface, usually with __regid__ = 'IFace' * use "adaptable('IFace')" as selector instead Also, the implements_adapter_compat decorator eases backward compatibility with adapter's methods that may still be found on entities implementing the interface. Notice that unlike ZCA, we don't support automatic adapters chain (yagni?). All interfaces defined in cubicweb have been turned into adapters, also some new ones have been introduced to cleanup Entity / AnyEntity classes namespace. At the end, the pluggable mixins mecanism should disappear in favor of adapters as well.

"""twisted server for CubicWeb web instances

:organization: Logilab
:copyright: 2001-2010 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses
"""

__docformat__ = "restructuredtext en"

from cubicweb.web.http_headers import Headers

class HTTPResponse(object):
    """An object representing an HTTP Response to be sent to the client.
    """
    def __init__(self, twisted_request, code=None, headers=None, stream=None):
        self._headers_out = headers
        self._twreq = twisted_request
        self._stream = stream
        self._code = code

        self._init_headers()
        self._finalize()

    def _init_headers(self):
        if self._headers_out is None:
            return

        # initialize cookies
        cookies = self._headers_out.getHeader('set-cookie') or []
        for cookie in cookies:
            self._twreq.addCookie(cookie.name, cookie.value, cookie.expires,
                                  cookie.domain, cookie.path, #TODO max-age
                                  comment = cookie.comment, secure=cookie.secure)
        self._headers_out.removeHeader('set-cookie')

        # initialize other headers
        for k, v in self._headers_out.getAllRawHeaders():
            self._twreq.setHeader(k, v[0])

        # add content-length if not present
        if (self._headers_out.getHeader('content-length') is None
            and self._stream is not None):
           self._twreq.setHeader('content-length', len(self._stream))


    def _finalize(self):
        # we must set code before writing anything, else it's too late
        if self._code is not None:
            self._twreq.setResponseCode(self._code)
        if self._stream is not None:
            self._twreq.write(str(self._stream))
        self._twreq.finish()

    def __repr__(self):
        return "<%s.%s code=%d>" % (self.__module__, self.__class__.__name__, self._code)


def not_modified_response(twisted_request, headers_in):
    headers_out = Headers()

    for header in (
        # Required from sec 10.3.5:
        'date', 'etag', 'content-location', 'expires',
        'cache-control', 'vary',
        # Others:
        'server', 'proxy-authenticate', 'www-authenticate', 'warning'):
        value = headers_in.getRawHeaders(header)
        if value is not None:
            headers_out.setRawHeaders(header, value)
    return HTTPResponse(twisted_request=twisted_request,
                        headers=headers_out)