converting to and from octal escaped UTF--8

[MonkeeSage]

On Dec 2, 11:46 pm, Michael Spencer <m... at telcopartners.com> wrote:
> Michael Goerz wrote:
> > Hi,
>
> > I am writing unicode stings into a special text file that requires to
> > have non-ascii characters as as octal-escaped UTF-8 codes.
>
> > For example, the letter "Í" (latin capital I with acute, code point 205)
> > would come out as "\303\215".
>
> > I will also have to read back from the file later on and convert the
> > escaped characters back into a unicode string.
>
> > Does anyone have any suggestions on how to go from "Í" to "\303\215" and
> > vice versa?
>
> Perhaps something along the lines of:
>
>   >>> def encode(source):
>   ...     return "".join("\%o" % ord(c) for c in source.encode('utf8'))
>   ...
>   >>> def decode(encoded):
>   ...     bytes = "".join(chr(int(c, 8)) for c in encoded.split('\\')[1:])
>   ...     return bytes.decode('utf8')
>   ...
>   >>> encode(u"Í")
>   '\\303\\215'
>   >>> print decode(_)
>   Í
>   >>>
>
> HTH
> Michael

Nice one. :) If I might suggest a slight variation to handle cases
where the "encoded" string contains plain text as well as octal
escapes...

def decode(encoded):
  for octc in (c for c in re.findall(r'\\(\d{3})', encoded)):
    encoded = encoded.replace(r'\%s' % octc, chr(int(octc, 8)))
  return encoded.decode('utf8')

This way it can handle both "\\141\\144\\146\\303\\215\\141\\144\\146"
as well as "adf\\303\\215adf".

Regards,
Jordan