oslo.serialization/doc
Victor Stinner e49e812900 Add utilities for base64
Writing a code using the base64 module (of the Python standard
library) working on Python 2.7 and 3.4 requires many checks on the
input and/or output type:

* base64.b64encode() only accepts byte string: text must be
  explicitly encoded to ASCII
* base64.b64decode() returns bytes: output must be decoded from UTF-8
  when text is expected

This change adds two pairs of encode/decode functions:

* encode_as_bytes(), decode_as_bytes(): always return the result as
  a byte string
* encode_as_text(), decode_as_text(): always return the result as a
  text string

Encode functions accept text: text is encoded to UTF-8 by default,
but the encoding is configurable.

Decode functions accept text: text is decoded from ASCII.

decode_as_text() decodes the result from UTF-8 by default, but again
the encoding is configurable.


The new submodule is called "base64" to be able to replace:

    import base64

with:

    from oslo_serialization import base64

If the base64 module of the stdlib is needed, it can be imported as a
different name. Example:

    import base64 as std_base64


The encoding example:

    if isinstance(text, six.text_type):
       text = text.encode('utf-8')
    text_b64 = base64.b64encode(text)
    text_b64 = text_b64.decode('ascii')

can be replaced with:

    text_b64 = base64.encode_as_text(text)


The decoding example:

    if isinstance(encoded, six.text_type):
       encoded = encoded.decode('ascii')
    text = base64.b64decode(encoded)
    text = text.decode('utf-8')

can be replaced with:

    text = base64.decode_as_text(text)

Change-Id: Icf8df9c947bc0c5f4838508b756ed8f53efd9fc4
2015-10-01 14:32:29 +00:00
..
source Add utilities for base64 2015-10-01 14:32:29 +00:00