email.mime: 从头创建电子邮件和 MIME 对象

源代码: Lib/email/mime/

此模块是旧版 (Compat32) 电子邮件 API 的组成部分。 它的功能在新版 API 中被 contentmanager 部分替代，但在某些应用中这些类仍可能有用，即使是在非旧版代码中。

通常，你是通过传递一个文件或一些文本到解析器来获得消息对象结构体的，解析器会解析文本并返回根消息对象。 不过你也可以从头开始构建一个完整的消息结构体，甚至是手动构建单独的 Message 对象。 实际上，你也可以接受一个现有的结构体并添加新的 Message 对象并移动它们。 这为切片和分割 MIME 消息提供了非常方便的接口。

你可以通过创建 Message 实例并手动添加附件和所有适当的标头来创建一个新的对象结构体。 不过对于 MIME 消息来说，email 包提供了一些便捷子类来让事情变得更容易。

这些类列示如下:

class email.mime.base.MIMEBase(_maintype, _subtype, *, policy=compat32, **_params)

模块: email.mime.base

This is the base class for all the MIME-specific subclasses of Message. Ordinarily you won't create instances specifically of MIMEBase, although you could. MIMEBase is provided primarily as a convenient base class for more specific MIME-aware subclasses.

_maintype is the Content-Type major type (e.g. text or image), and _subtype is the Content-Type minor type (e.g. plain or gif). _params is a parameter key/value dictionary and is passed directly to Message.add_header.

If policy is specified, (defaults to the compat32 policy) it will be passed to Message.

The MIMEBase class always adds a Content-Type header (based on _maintype, _subtype, and _params), and a MIME-Version header (always set to 1.0).

在 3.6 版更改: Added policy keyword-only parameter.

class email.mime.nonmultipart.MIMENonMultipart

Module: email.mime.nonmultipart

A subclass of MIMEBase, this is an intermediate base class for MIME messages that are not multipart. The primary purpose of this class is to prevent the use of the attach() method, which only makes sense for multipart messages. If attach() is called, a MultipartConversionError exception is raised.

class email.mime.multipart.MIMEMultipart(_subtype='mixed', boundary=None, _subparts=None, *, policy=compat32, **_params)

Module: email.mime.multipart

A subclass of MIMEBase, this is an intermediate base class for MIME messages that are multipart. Optional _subtype defaults to mixed, but can be used to specify the subtype of the message. A Content-Type header of multipart/_subtype will be added to the message object. A MIME-Version header will also be added.

Optional boundary is the multipart boundary string. When None (the default), the boundary is calculated when needed (for example, when the message is serialized).

_subparts is a sequence of initial subparts for the payload. It must be possible to convert this sequence to a list. You can always attach new subparts to the message by using the Message.attach method.

Optional policy argument defaults to compat32.

Additional parameters for the Content-Type header are taken from the keyword arguments, or passed into the _params argument, which is a keyword dictionary.

在 3.6 版更改: Added policy keyword-only parameter.

class email.mime.application.MIMEApplication(_data, _subtype='octet-stream', _encoder=email.encoders.encode_base64, *, policy=compat32, **_params)

Module: email.mime.application

A subclass of MIMENonMultipart, the MIMEApplication class is used to represent MIME message objects of major type application. _data is a string containing the raw byte data. Optional _subtype specifies the MIME subtype and defaults to octet-stream.

Optional _encoder is a callable (i.e. function) which will perform the actual encoding of the data for transport. This callable takes one argument, which is the MIMEApplication instance. It should use get_payload() and set_payload() to change the payload to encoded form. It should also add any Content-Transfer-Encoding or other headers to the message object as necessary. The default encoding is base64. See the email.encoders module for a list of the built-in encoders.

Optional policy argument defaults to compat32.

_params are passed straight through to the base class constructor.

在 3.6 版更改: Added policy keyword-only parameter.

class email.mime.audio.MIMEAudio(_audiodata, _subtype=None, _encoder=email.encoders.encode_base64, *, policy=compat32, **_params)

Module: email.mime.audio

A subclass of MIMENonMultipart, the MIMEAudio class is used to create MIME message objects of major type audio. _audiodata is a string containing the raw audio data. If this data can be decoded by the standard Python module sndhdr, then the subtype will be automatically included in the Content-Type header. Otherwise you can explicitly specify the audio subtype via the _subtype argument. If the minor type could not be guessed and _subtype was not given, then TypeError is raised.

Optional _encoder is a callable (i.e. function) which will perform the actual encoding of the audio data for transport. This callable takes one argument, which is the MIMEAudio instance. It should use get_payload() and set_payload() to change the payload to encoded form. It should also add any Content-Transfer-Encoding or other headers to the message object as necessary. The default encoding is base64. See the email.encoders module for a list of the built-in encoders.

Optional policy argument defaults to compat32.

_params are passed straight through to the base class constructor.

在 3.6 版更改: Added policy keyword-only parameter.

class email.mime.image.MIMEImage(_imagedata, _subtype=None, _encoder=email.encoders.encode_base64, *, policy=compat32, **_params)

Module: email.mime.image

A subclass of MIMENonMultipart, the MIMEImage class is used to create MIME message objects of major type image. _imagedata is a string containing the raw image data. If this data can be decoded by the standard Python module imghdr, then the subtype will be automatically included in the Content-Type header. Otherwise you can explicitly specify the image subtype via the _subtype argument. If the minor type could not be guessed and _subtype was not given, then TypeError is raised.

Optional _encoder is a callable (i.e. function) which will perform the actual encoding of the image data for transport. This callable takes one argument, which is the MIMEImage instance. It should use get_payload() and set_payload() to change the payload to encoded form. It should also add any Content-Transfer-Encoding or other headers to the message object as necessary. The default encoding is base64. See the email.encoders module for a list of the built-in encoders.

Optional policy argument defaults to compat32.

_params are passed straight through to the MIMEBase constructor.

在 3.6 版更改: Added policy keyword-only parameter.

class email.mime.message.MIMEMessage(_msg, _subtype='rfc822', *, policy=compat32)

Module: email.mime.message

A subclass of MIMENonMultipart, the MIMEMessage class is used to create MIME objects of main type message. _msg is used as the payload, and must be an instance of class Message (or a subclass thereof), otherwise a TypeError is raised.

Optional _subtype sets the subtype of the message; it defaults to rfc822.

Optional policy argument defaults to compat32.

在 3.6 版更改: Added policy keyword-only parameter.

class email.mime.text.MIMEText(_text, _subtype='plain', _charset=None, *, policy=compat32)

Module: email.mime.text

A subclass of MIMENonMultipart, the MIMEText class is used to create MIME objects of major type text. _text is the string for the payload. _subtype is the minor type and defaults to plain. _charset is the character set of the text and is passed as an argument to the MIMENonMultipart constructor; it defaults to us-ascii if the string contains only ascii code points, and utf-8 otherwise. The _charset parameter accepts either a string or a Charset instance.

Unless the _charset argument is explicitly set to None, the MIMEText object created will have both a Content-Type header with a charset parameter, and a Content-Transfer-Encoding header. This means that a subsequent set_payload call will not result in an encoded payload, even if a charset is passed in the set_payload command. You can "reset" this behavior by deleting the Content-Transfer-Encoding header, after which a set_payload call will automatically encode the new payload (and add a new Content-Transfer-Encoding header).

Optional policy argument defaults to compat32.

在 3.5 版更改: _charset also accepts Charset instances.

在 3.6 版更改: Added policy keyword-only parameter.