[Zope3-dev] Important IFile bug!

[Jim Fulton]

Roger Ineichen wrote:

...

> Ok, what can I do?
> 
> Should I implement a IData field and enhance this field?

I think you should define an IMime schema that defines methods
to get and set the data. I suggest that this should be a
file-like interface, with, at least, read and write.
It should have a mime-type attribute and an encoding
attribute, for use with text.

Then you should define a mine field (IMImeField/MimeField)
for data with this interface.

Finally, you need a widget.

The widget should support:

- file-upload

- text area if content type is text/* *and* if an encoding
   is specified.

- entry of content type and, for text types, the encoding

> The validate method of this field should allowes to store 
> String and FileChunk? Others?

The validate method should accept strings and objects
with read methods.

> Is there a python lib for reading files and find the 
> content type like stefan was implementing for images?

Of course, in the unlikely event that the client sends the
file type and/or encoding with the file upload, you should
use that information.  Otherwise, use zope.app.content_types,
which seems to use the Python mimetypes module.

If you feel especially inspired, it would be nice to store
file-upload data in a session if someone submits a form
with a file-upload using other than the main submit
button or if there are validation errors on other fields.
IOW, it would be cool if the widget stored the data in a
session so that the data wasn't lost on a redisplay.

Jim

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