1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
:mod:`!email.contentmanager`: Managing MIME Content
---------------------------------------------------
.. module:: email.contentmanager
:synopsis: Storing and Retrieving Content from MIME Parts
.. moduleauthor:: R. David Murray <rdmurray@bitdance.com>
.. sectionauthor:: R. David Murray <rdmurray@bitdance.com>
**Source code:** :source:`Lib/email/contentmanager.py`
------------
.. versionadded:: 3.6 [1]_
.. class:: ContentManager()
Base class for content managers. Provides the standard registry mechanisms
to register converters between MIME content and other representations, as
well as the ``get_content`` and ``set_content`` dispatch methods.
.. method:: get_content(msg, *args, **kw)
Look up a handler function based on the ``mimetype`` of *msg* (see next
paragraph), call it, passing through all arguments, and return the result
of the call. The expectation is that the handler will extract the
payload from *msg* and return an object that encodes information about
the extracted data.
To find the handler, look for the following keys in the registry,
stopping with the first one found:
* the string representing the full MIME type (``maintype/subtype``)
* the string representing the ``maintype``
* the empty string
If none of these keys produce a handler, raise a :exc:`KeyError` for the
full MIME type.
.. method:: set_content(msg, obj, *args, **kw)
If the ``maintype`` is ``multipart``, raise a :exc:`TypeError`; otherwise
look up a handler function based on the type of *obj* (see next
paragraph), call :meth:`~email.message.EmailMessage.clear_content` on the
*msg*, and call the handler function, passing through all arguments. The
expectation is that the handler will transform and store *obj* into
*msg*, possibly making other changes to *msg* as well, such as adding
various MIME headers to encode information needed to interpret the stored
data.
To find the handler, obtain the type of *obj* (``typ = type(obj)``), and
look for the following keys in the registry, stopping with the first one
found:
* the type itself (``typ``)
* the type's fully qualified name (``typ.__module__ + '.' +
typ.__qualname__``).
* the type's qualname (``typ.__qualname__``)
* the type's name (``typ.__name__``).
If none of the above match, repeat all of the checks above for each of
the types in the :term:`MRO` (``typ.__mro__``). Finally, if no other key
yields a handler, check for a handler for the key ``None``. If there is
no handler for ``None``, raise a :exc:`KeyError` for the fully
qualified name of the type.
Also add a :mailheader:`MIME-Version` header if one is not present (see
also :class:`.MIMEPart`).
.. method:: add_get_handler(key, handler)
Record the function *handler* as the handler for *key*. For the possible
values of *key*, see :meth:`get_content`.
.. method:: add_set_handler(typekey, handler)
Record *handler* as the function to call when an object of a type
matching *typekey* is passed to :meth:`set_content`. For the possible
values of *typekey*, see :meth:`set_content`.
Content Manager Instances
~~~~~~~~~~~~~~~~~~~~~~~~~
Currently the email package provides only one concrete content manager,
:data:`raw_data_manager`, although more may be added in the future.
:data:`raw_data_manager` is the
:attr:`~email.policy.EmailPolicy.content_manager` provided by
:attr:`~email.policy.EmailPolicy` and its derivatives.
.. data:: raw_data_manager
This content manager provides only a minimum interface beyond that provided
by :class:`~email.message.Message` itself: it deals only with text, raw
byte strings, and :class:`~email.message.Message` objects. Nevertheless, it
provides significant advantages compared to the base API: ``get_content`` on
a text part will return a unicode string without the application needing to
manually decode it, ``set_content`` provides a rich set of options for
controlling the headers added to a part and controlling the content transfer
encoding, and it enables the use of the various ``add_`` methods, thereby
simplifying the creation of multipart messages.
.. method:: get_content(msg, errors='replace')
Return the payload of the part as either a string (for ``text`` parts), an
:class:`~email.message.EmailMessage` object (for ``message/rfc822``
parts), or a ``bytes`` object (for all other non-multipart types). Raise
a :exc:`KeyError` if called on a ``multipart``. If the part is a
``text`` part and *errors* is specified, use it as the error handler when
decoding the payload to unicode. The default error handler is
``replace``.
.. method:: set_content(msg, <'str'>, subtype="plain", charset='utf-8', \
cte=None, \
disposition=None, filename=None, cid=None, \
params=None, headers=None)
set_content(msg, <'bytes'>, maintype, subtype, cte="base64", \
disposition=None, filename=None, cid=None, \
params=None, headers=None)
set_content(msg, <'EmailMessage'>, cte=None, \
disposition=None, filename=None, cid=None, \
params=None, headers=None)
Add headers and payload to *msg*:
Add a :mailheader:`Content-Type` header with a ``maintype/subtype``
value.
* For ``str``, set the MIME ``maintype`` to ``text``, and set the
subtype to *subtype* if it is specified, or ``plain`` if it is not.
* For ``bytes``, use the specified *maintype* and *subtype*, or
raise a :exc:`TypeError` if they are not specified.
* For :class:`~email.message.EmailMessage` objects, set the maintype
to ``message``, and set the subtype to *subtype* if it is
specified or ``rfc822`` if it is not. If *subtype* is
``partial``, raise an error (``bytes`` objects must be used to
construct ``message/partial`` parts).
If *charset* is provided (which is valid only for ``str``), encode the
string to bytes using the specified character set. The default is
``utf-8``. If the specified *charset* is a known alias for a standard
MIME charset name, use the standard charset instead.
If *cte* is set, encode the payload using the specified content transfer
encoding, and set the :mailheader:`Content-Transfer-Encoding` header to
that value. Possible values for *cte* are ``quoted-printable``,
``base64``, ``7bit``, ``8bit``, and ``binary``. If the input cannot be
encoded in the specified encoding (for example, specifying a *cte* of
``7bit`` for an input that contains non-ASCII values), raise a
:exc:`ValueError`.
* For ``str`` objects, if *cte* is not set use heuristics to
determine the most compact encoding.
* For :class:`~email.message.EmailMessage`, per :rfc:`2046`, raise
an error if a *cte* of ``quoted-printable`` or ``base64`` is
requested for *subtype* ``rfc822``, and for any *cte* other than
``7bit`` for *subtype* ``external-body``. For
``message/rfc822``, use ``8bit`` if *cte* is not specified. For
all other values of *subtype*, use ``7bit``.
.. note:: A *cte* of ``binary`` does not actually work correctly yet.
The ``EmailMessage`` object as modified by ``set_content`` is
correct, but :class:`~email.generator.BytesGenerator` does not
serialize it correctly.
If *disposition* is set, use it as the value of the
:mailheader:`Content-Disposition` header. If not specified, and
*filename* is specified, add the header with the value ``attachment``.
If *disposition* is not specified and *filename* is also not specified,
do not add the header. The only valid values for *disposition* are
``attachment`` and ``inline``.
If *filename* is specified, use it as the value of the ``filename``
parameter of the :mailheader:`Content-Disposition` header.
If *cid* is specified, add a :mailheader:`Content-ID` header with
*cid* as its value.
If *params* is specified, iterate its ``items`` method and use the
resulting ``(key, value)`` pairs to set additional parameters on the
:mailheader:`Content-Type` header.
If *headers* is specified and is a list of strings of the form
``headername: headervalue`` or a list of ``header`` objects
(distinguished from strings by having a ``name`` attribute), add the
headers to *msg*.
.. rubric:: Footnotes
.. [1] Originally added in 3.4 as a :term:`provisional module <provisional
package>`
|
