[Zope3-Users] Re: why does HTTPResponse insist on a text mime type for unicode?

[Philipp von Weitershausen]

Stefan Rank wrote:
> I am trying to make my content object IExternallyEditable, and I ran up
> against the following code in
> zope.publisher.http.HTTPResult._implicitResult (line 849ff)::
> 
>     if isinstance(body, unicode):
>         try:
>             if not content_type.startswith('text/'):
>                 raise ValueError(
>                     'Unicode results must have a text content type,'
>                     'got %s.' % content_type)
>         except AttributeError:
>                 raise ValueError(
>                     'Unicode results must have a text content type.')
> 
> (note: the first raise originally did not give the feedback about the
> received content type.)
> 
> And my question is: Why? (do unicode results need to have a text/* type)

Unicode can't be sent over the wire. Hence the publisher will have to
encode it with a proper encoding (e.g. UTF-8) before transmitting the
data. When doing so, it will have to set the charset in the response.
AFAIK only text/* responses are supposed to have a charset parameter,
because everything else is just byte strings.

> The reason AFAICT is that my content object just stores its source as
> unicode object and simply provides that in its IReadFile adapter.

IReadFile should really return byte strings, not unicode.

Philipp