http.cookies — HTTP 状态管理

源代码: Lib/http/cookies.py


http.cookies module defines classes for abstracting the concept of cookies, an HTTP state management mechanism. It supports both simple string-only cookies, and provides an abstraction for having any serializable data-type as cookie value.

The module formerly strictly applied the parsing rules described in the RFC 2109 and RFC 2068 specifications. It has since been discovered that MSIE 3.0x doesn’t follow the character rules outlined in those specs and also many current day browsers and servers have relaxed parsing rules when comes to Cookie handling. As a result, the parsing rules used are a bit less strict.

字符集, string.ascii_letters , string.digits and !#$%&'*+-.^_`|~: denote the set of valid characters allowed by this module in Cookie name (as key ).

3.3 版改变: 允许 : 作为有效 Cookie 名称字符。

注意

On encountering an invalid cookie, CookieError is raised, so if your cookie data comes from a browser you should always prepare for invalid data and catch CookieError on parsing.

exception http.cookies. CookieError

Exception failing because of RFC 2109 invalidity: incorrect attributes, incorrect Set-Cookie header, etc.

class http.cookies. BaseCookie ( [ input ] )

This class is a dictionary-like object whose keys are strings and whose values are Morsel instances. Note that upon setting a key to a value, the value is first converted to a Morsel containing the key and the value.

input 有给定,会被传递给 load() 方法。

class http.cookies. SimpleCookie ( [ input ] )

此类派生自 BaseCookie 和覆盖 value_decode() and value_encode() . SimpleCookie supports strings as cookie values. When setting the value, SimpleCookie calls the builtin str() to convert the value to a string. Values received from HTTP are kept as strings.

另请参阅

模块 http.cookiejar

HTTP cookie handling for web clients http.cookiejar and http.cookies 模块不相互依赖。

RFC 2109 - HTTP 状态管理机制

这是由此模块实现的状态管理规范。

Morsel Objects

class http.cookies. Morsel

抽象键/值对,有一些 RFC 2109 属性。

Morsels are dictionary-like objects, whose set of keys is constant — the valid RFC 2109 attributes, which are

  • expires

  • path

  • comment

  • domain

  • max-age

  • secure

  • version

  • httponly

  • samesite

属性 httponly specifies that the cookie is only transferred in HTTP requests, and is not accessible through JavaScript. This is intended to mitigate some forms of cross-site scripting.

属性 samesite specifies that the browser is not allowed to send the cookie along with cross-site requests. This helps to mitigate CSRF attacks. Valid values for this attribute are “Strict” and “Lax”.

The keys are case-insensitive and their default value is '' .

3.5 版改变: __eq__() now takes key and value into account.

3.7 版改变: 属性 key , value and coded_value are read-only. Use set() for setting them.

3.8 版改变: 添加支持 samesite 属性。

Morsel. value

Cookie 的值。

Morsel. coded_value

The encoded value of the cookie — this is what should be sent.

Morsel. key

Cookie 的名称。

Morsel. set ( key , value , coded_value )

设置 key , value and coded_value 属性。

Morsel. isReservedKey ( K )

Whether K is a member of the set of keys of a Morsel .

Morsel. output ( attrs=None , header='Set-Cookie:' )

Return a string representation of the Morsel, suitable to be sent as an HTTP header. By default, all the attributes are included, unless attrs is given, in which case it should be a list of attributes to use. header is by default "Set-Cookie:" .

Morsel. js_output ( attrs=None )

Return an embeddable JavaScript snippet, which, if run on a browser which supports JavaScript, will act the same as if the HTTP header was sent.

The meaning for attrs is the same as in output() .

Morsel. OutputString ( attrs=None )

Return a string representing the Morsel, without any surrounding HTTP or JavaScript.

The meaning for attrs is the same as in output() .

Morsel. update ( values )

Update the values in the Morsel dictionary with the values in the dictionary values . Raise an error if any of the keys in the values dict is not a valid RFC 2109 属性。

3.5 版改变: an error is raised for invalid keys.

Morsel. copy ( value )

Return a shallow copy of the Morsel object.

3.5 版改变: return a Morsel object instead of a dict.

Morsel. setdefault ( key , value=None )

引发错误若键不是有效 RFC 2109 属性,否则行为如同 dict.setdefault() .

范例

以下范例演示如何使用 http.cookies 模块。

>>> from http import cookies
>>> C = cookies.SimpleCookie()
>>> C["fig"] = "newton"
>>> C["sugar"] = "wafer"
>>> print(C) # generate HTTP headers
Set-Cookie: fig=newton
Set-Cookie: sugar=wafer
>>> print(C.output()) # same thing
Set-Cookie: fig=newton
Set-Cookie: sugar=wafer
>>> C = cookies.SimpleCookie()
>>> C["rocky"] = "road"
>>> C["rocky"]["path"] = "/cookie"
>>> print(C.output(header="Cookie:"))
Cookie: rocky=road; Path=/cookie
>>> print(C.output(attrs=[], header="Cookie:"))
Cookie: rocky=road
>>> C = cookies.SimpleCookie()
>>> C.load("chips=ahoy; vienna=finger") # load from a string (HTTP header)
>>> print(C)
Set-Cookie: chips=ahoy
Set-Cookie: vienna=finger
>>> C = cookies.SimpleCookie()
>>> C.load('keebler="E=everybody; L=\\"Loves\\"; fudge=\\012;";')
>>> print(C)
Set-Cookie: keebler="E=everybody; L=\"Loves\"; fudge=\012;"
>>> C = cookies.SimpleCookie()
>>> C["oreo"] = "doublestuff"
>>> C["oreo"]["path"] = "/"
>>> print(C)
Set-Cookie: oreo=doublestuff; Path=/
>>> C = cookies.SimpleCookie()
>>> C["twix"] = "none for you"
>>> C["twix"].value
'none for you'
>>> C = cookies.SimpleCookie()
>>> C["number"] = 7 # equivalent to C["number"] = str(7)
>>> C["string"] = "seven"
>>> C["number"].value
'7'
>>> C["string"].value
'seven'
>>> print(C)
Set-Cookie: number=7
Set-Cookie: string=seven