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) 
>>> 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.

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