This demonstrates how the Response object works, and tests it at the
same time.

    >>> from doctest import ELLIPSIS
    >>> from webob import Response, UTC
    >>> from datetime import datetime
    >>> res = Response('Test', status='200 OK')

This is a minimal response object.  We can do things like get and set
the body:

    >>> res.body
    'Test'
    >>> res.body = 'Another test'
    >>> res.body
    'Another test'
    >>> res.body = 'Another'
    >>> res.write(' test')
    >>> res.app_iter
    ['Another', ' test']
    >>> res.content_length
    12
    >>> res.headers['content-length']
    '12'

Content-Length is only applied when setting the body to a string; you
have to set it manually otherwise.  There are also getters and setters
for the various pieces:

    >>> res.app_iter = ['test']
    >>> print res.content_length
    None
    >>> res.content_length = 4
    >>> res.status
    '200 OK'
    >>> res.status_int
    200
    >>> res.headers
    ResponseHeaders([('Content-Type', 'text/html; charset=UTF-8'), ('Content-Length', '4')])
    >>> res.headerlist
    [('Content-Type', 'text/html; charset=UTF-8'), ('Content-Length', '4')]

Content-type and charset are handled separately as properties, though
they are both in the ``res.headers['content-type']`` header:

    >>> res.content_type
    'text/html'
    >>> res.content_type = 'text/html'
    >>> res.content_type
    'text/html'
    >>> res.charset
    'UTF-8'
    >>> res.charset = 'iso-8859-1'
    >>> res.charset
    'iso-8859-1'
    >>> res.content_type
    'text/html'
    >>> res.headers['content-type']
    'text/html; charset=iso-8859-1'

Cookie handling is done through methods:

    >>> res.set_cookie('test', 'value')
    >>> res.headers['set-cookie']
    'test=value; Path=/'
    >>> res.set_cookie('test2', 'value2', max_age=10000)
    >>> res.headers['set-cookie'] # We only see the last header
    'test2=value2; Max-Age=10000; Path=/; expires=... GMT'
    >>> res.headers.getall('set-cookie')
    ['test=value; Path=/', 'test2=value2; Max-Age=10000; Path=/; expires=... GMT']
    >>> res.unset_cookie('test')
    >>> res.headers.getall('set-cookie')
    ['test2=value2; Max-Age=10000; Path=/; expires=... GMT']
    >>> res.set_cookie('test2', 'value2-add')
    >>> res.headers.getall('set-cookie')
    ['test2=value2; Max-Age=10000; Path=/; expires=... GMT', 'test2=value2-add; Path=/']
    >>> res.set_cookie('test2', 'value2-replace', overwrite=True)
    >>> res.headers.getall('set-cookie')
    ['test2=value2-replace; Path=/']


    >>> r = Response()
    >>> r.set_cookie('x', 'x')
    >>> r.set_cookie('y', 'y')
    >>> r.set_cookie('z', 'z')
    >>> r.headers.getall('set-cookie')
    ['x=x; Path=/', 'y=y; Path=/', 'z=z; Path=/']
    >>> r.unset_cookie('y')
    >>> r.headers.getall('set-cookie')
    ['x=x; Path=/', 'z=z; Path=/']


Most headers are available in a parsed getter/setter form through
properties:

    >>> res.age = 10
    >>> res.age, res.headers['age']
    (10, '10')
    >>> res.allow = ['GET', 'PUT']
    >>> res.allow, res.headers['allow']
    (('GET', 'PUT'), 'GET, PUT')
    >>> res.cache_control
    <CacheControl ''>
    >>> print res.cache_control.max_age
    None
    >>> res.cache_control.properties['max-age'] = None
    >>> print res.cache_control.max_age
    -1
    >>> res.cache_control.max_age = 10
    >>> res.cache_control
    <CacheControl 'max-age=10'>
    >>> res.headers['cache-control']
    'max-age=10'
    >>> res.cache_control.max_stale = 10
    Traceback (most recent call last):
        ...
    AttributeError: The property max-stale only applies to request Cache-Control
    >>> res.cache_control = {}
    >>> res.cache_control
    <CacheControl ''>
    >>> res.content_disposition = 'attachment; filename=foo.xml'
    >>> (res.content_disposition, res.headers['content-disposition'])
    ('attachment; filename=foo.xml', 'attachment; filename=foo.xml')
    >>> res.content_encoding = 'gzip'
    >>> (res.content_encoding, res.headers['content-encoding'])
    ('gzip', 'gzip')
    >>> res.content_language = 'en'
    >>> (res.content_language, res.headers['content-language'])
    (('en',), 'en')
    >>> res.content_location = 'http://localhost:8080'
    >>> res.headers['content-location']
    'http://localhost:8080'
    >>> res.content_range = (0, 100, 1000)
    >>> (res.content_range, res.headers['content-range'])
    (<ContentRange bytes 0-99/1000>, 'bytes 0-99/1000')
    >>> res.date = datetime(2005, 1, 1, 12, 0, tzinfo=UTC)
    >>> (res.date, res.headers['date'])
    (datetime.datetime(2005, 1, 1, 12, 0, tzinfo=UTC), 'Sat, 01 Jan 2005 12:00:00 GMT')
    >>> print res.etag
    None
    >>> res.etag = 'foo'
    >>> (res.etag, res.headers['etag'])
    ('foo', '"foo"')
    >>> res.etag = 'something-with-"quotes"'
    >>> (res.etag, res.headers['etag'])
    ('something-with-"quotes"', '"something-with-\\"quotes\\""')
    >>> res.expires = res.date
    >>> res.retry_after = 120 # two minutes
    >>> res.retry_after
    datetime.datetime(...)
    >>> res.server = 'Python/foo'
    >>> res.headers['server']
    'Python/foo'
    >>> res.vary = ['Cookie']
    >>> (res.vary, res.headers['vary'])
    (('Cookie',), 'Cookie')

The location header will absolutify itself when the response
application is actually served.  We can force this with
``req.get_response``::

    >>> res.location = '/test.html'
    >>> from webob import Request
    >>> req = Request.blank('/')
    >>> res.location
    '/test.html'
    >>> req.get_response(res).location
    'http://localhost/test.html'
    >>> res.location = '/test2.html'
    >>> req.get_response(res).location
    'http://localhost/test2.html'

There's some conditional response handling too (you have to turn on
conditional_response)::

    >>> res = Response('abc', conditional_response=True) # doctest: +ELLIPSIS
    >>> req = Request.blank('/')
    >>> res.etag = 'tag'
    >>> req.if_none_match = 'tag'
    >>> req.get_response(res)
    <Response ... 304 Not Modified>
    >>> res.etag = 'other-tag'
    >>> req.get_response(res)
    <Response ... 200 OK>
    >>> del req.if_none_match
    >>> req.if_modified_since = datetime(2005, 1, 1, 12, 1, tzinfo=UTC)
    >>> res.last_modified = datetime(2005, 1, 1, 12, 1, tzinfo=UTC)
    >>> print req.get_response(res)
    304 Not Modified
    ETag: "other-tag"
    Last-Modified: Sat, 01 Jan 2005 12:01:00 GMT
    >>> res.last_modified = datetime(2006, 1, 1, 12, 1, tzinfo=UTC)
    >>> req.get_response(res)
    <Response ... 200 OK>
    >>> res.last_modified = None
    >>> req.get_response(res)
    <Response ... 200 OK>

Weak etags::

    >>> req = Request.blank('/', if_none_match='W/"test"')
    >>> res = Response(conditional_response=True, etag='test')
    >>> req.get_response(res).status
    '304 Not Modified'

Also range response::

    >>> res = Response('0123456789', conditional_response=True)
    >>> req = Request.blank('/', range=(1, 5))
    >>> req.range
    <Range ranges=(1, 5)>
    >>> str(req.range)
    'bytes=1-4'
    >>> result = req.get_response(res)
    >>> result.body
    '1234'
    >>> result.content_range.stop
    5
    >>> result.content_range
    <ContentRange bytes 1-4/10>
    >>> tuple(result.content_range)
    (1, 5, 10)
    >>> result.content_length
    4


    >>> req.range = (5, 20)
    >>> str(req.range)
    'bytes=5-19'
    >>> result = req.get_response(res)
    >>> print result
    206 Partial Content
    Content-Length: 5
    Content-Range: bytes 5-9/10
    Content-Type: text/html; charset=UTF-8
    <BLANKLINE>
    56789
    >>> tuple(result.content_range)
    (5, 10, 10)

    >>> req_head = req.copy()
    >>> req_head.method = 'HEAD'
    >>> print req_head.get_response(res)
    206 Partial Content
    Content-Length: 5
    Content-Range: bytes 5-9/10
    Content-Type: text/html; charset=UTF-8

And an invalid requested range:

    >>> req.range = (10, 20)
    >>> result = req.get_response(res)
    >>> print result
    416 Requested Range Not Satisfiable
    Content-Length: 44
    Content-Range: bytes */10
    Content-Type: text/plain
    <BLANKLINE>
    Requested range not satisfiable: bytes=10-19
    >>> str(result.content_range)
    'bytes */10'

    >>> req_head = req.copy()
    >>> req_head.method = 'HEAD'
    >>> print req_head.get_response(res)
    416 Requested Range Not Satisfiable
    Content-Length: 44
    Content-Range: bytes */10
    Content-Type: text/plain

    >>> Request.blank('/', range=(1,2)).get_response(
    ...     Response('0123456789', conditional_response=True)).content_length
    1


That was easier; we'll try it with a iterator for the body::

    >>> res = Response(conditional_response=True)
    >>> res.app_iter = ['01234', '567', '89']
    >>> req = Request.blank('/')
    >>> req.range = (1, 5)
    >>> result = req.get_response(res)

Because we don't know the length of the app_iter, this doesn't work::

    >>> result.body
    '0123456789'
    >>> print result.content_range
    None

But it will, if we set content_length::
    >>> res.content_length = 10
    >>> req.range = (5, None)
    >>> result = req.get_response(res)
    >>> result.body
    '56789'
    >>> result.content_range
    <ContentRange bytes 5-9/10>


Ranges requesting x last bytes are supported too:

    >>> req.range = 'bytes=-1'
    >>> req.range
    <Range ranges=(-1, None)>
    >>> result = req.get_response(res)
    >>> result.body
    '9'
    >>> result.content_range
    <ContentRange bytes 9-9/10>
    >>> result.content_length
    1


If those ranges are not satisfiable, a 416 error is returned:

    >>> req.range = 'bytes=-100'
    >>> result = req.get_response(res)
    >>> result.status
    '416 Requested Range Not Satisfiable'
    >>> result.content_range
    <ContentRange bytes */10>
    >>> result.body
    'Requested range not satisfiable: bytes=-100'


If we set Content-Length then we can use it with an app_iter

    >>> res.content_length = 10
    >>> req.range = (1, 5) # python-style range
    >>> req.range
    <Range ranges=(1, 5)>
    >>> result = req.get_response(res)
    >>> result.body
    '1234'
    >>> result.content_range
    <ContentRange bytes 1-4/10>
    >>> # And trying If-modified-since
    >>> res.etag = 'foobar'
    >>> req.if_range = 'foobar'
    >>> req.if_range
    <IfRange etag="foobar", date=*>
    >>> result = req.get_response(res)
    >>> result.content_range
    <ContentRange bytes 1-4/10>
    >>> req.if_range = 'blah'
    >>> result = req.get_response(res)
    >>> result.content_range
    >>> req.if_range = datetime(2005, 1, 1, 12, 0, tzinfo=UTC)
    >>> res.last_modified = datetime(2005, 1, 1, 12, 0, tzinfo=UTC)
    >>> result = req.get_response(res)
    >>> result.content_range
    <ContentRange bytes 1-4/10>
    >>> res.last_modified = datetime(2006, 1, 1, 12, 0, tzinfo=UTC)
    >>> result = req.get_response(res)
    >>> result.content_range

Some tests of Content-Range parsing::

    >>> from webob.byterange import ContentRange
    >>> ContentRange.parse('bytes */*')
    <ContentRange bytes */*>
    >>> ContentRange.parse('bytes */10')
    <ContentRange bytes */10>
    >>> ContentRange.parse('bytes 5-9/10')
    <ContentRange bytes 5-9/10>
    >>> ContentRange.parse('bytes 5-10/*')
    <ContentRange bytes 5-10/*>
    >>> print ContentRange.parse('bytes 5-10/10')
    None
    >>> print ContentRange.parse('bytes 5-4/10')
    None
    >>> print ContentRange.parse('bytes 5-*/10')
    None

Some tests of exceptions::

    >>> from webob import exc
    >>> res = exc.HTTPNotFound('Not found!')
    >>> res.content_type = 'text/plain'
    >>> res.content_type
    'text/plain'
    >>> res = exc.HTTPNotModified()
    >>> res.headers
    ResponseHeaders([])

Headers can be set to unicode values::

    >>> res = Response('test')
    >>> res.etag = u'fran\xe7ais'

But they come out as str::

    >>> res.etag
    'fran\xe7ais'


Unicode can come up in unexpected places, make sure it doesn't break things
(this particular case could be caused by a `from __future__ import unicode_literals`)::

    >>> Request.blank('/', method=u'POST').get_response(exc.HTTPMethodNotAllowed())
    <Response at ... 405 Method Not Allowed>

Copying Responses should copy their internal structures

    >>> r = Response(app_iter=[])
    >>> r2 = r.copy()
    >>> r.headerlist is r2.headerlist
    False
    >>> r.app_iter is r2.app_iter
    False

    >>> r = Response(app_iter=iter(['foo']))
    >>> r2 = r.copy()
    >>> del r2.content_type
    >>> r2.body_file.write(' bar')
    >>> print r
    200 OK
    Content-Type: text/html; charset=UTF-8
    <BLANKLINE>
    foo
    >>> print r2
    200 OK
    Content-Length: 7
    <BLANKLINE>
    foo bar


Additional Response constructor keywords are used to set attributes

    >>> r = Response(cache_expires=True)
    >>> r.headers['Cache-Control']
    'max-age=0, must-revalidate, no-cache, no-store'



    >>> from webob.exc import HTTPBadRequest
    >>> raise HTTPBadRequest('bad data')
    Traceback (most recent call last):
    ...
    HTTPBadRequest: bad data
    >>> raise HTTPBadRequest()
    Traceback (most recent call last):
    ...
    HTTPBadRequest: The server could not comply with the request since it is either malformed or otherwise incorrect.