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Oslo Style Commandments
=======================

- Step 1: Read the OpenStack Style Commandments
  http://docs.openstack.org/developer/hacking/
- Step 2: Read on

Oslo Specific Commandments
--------------------------
- None So Far



General
-------
- When defining global constants, define them before functions and classes
- Use 'raise' instead of 'raise e' to preserve original traceback or exception being reraised::

    except Exception as e:
        ...
        raise e  # BAD

    except Exception:
        ...
        raise  # OKAY

TODO vs FIXME
-------------
- TODO(name): implies that something should be done (cleanup, refactoring,
  etc), but is expected to be functional.
- FIXME(name): implies that the method/function/etc shouldn't be used until
  that code is resolved and bug fixed.


Text encoding
-------------
- All text within python code should be of type 'unicode'.

    WRONG:

    >>> s = 'foo'
    >>> s
    'foo'
    >>> type(s)
    <type 'str'>

    RIGHT:

    >>> u = u'foo'
    >>> u
    u'foo'
    >>> type(u)
    <type 'unicode'>

- Transitions between internal unicode and external strings should always
  be immediately and explicitly encoded or decoded.

- All external text that is not explicitly encoded (database storage,
  commandline arguments, etc.) should be presumed to be encoded as utf-8.

    WRONG:

    mystring = infile.readline()
    myreturnstring = do_some_magic_with(mystring)
    outfile.write(myreturnstring)

    RIGHT:

    mystring = infile.readline()
    mytext = s.decode('utf-8')
    returntext = do_some_magic_with(mytext)
    returnstring = returntext.encode('utf-8')
    outfile.write(returnstring)