[Zope3-dev] Important IFile bug!

[Jim Fulton]

Jim Fulton wrote:
> Roger Ineichen wrote:
> 
>> Ok I see...
>>
>>
>>> -----Original Message-----
>>> From: Jim Fulton [mailto:jim at zope.com] Sent: Monday, January 17, 2005 
>>> 12:58 PM
>>> To: dev at projekt01.ch
>>> Cc: zope3-dev at zope.org
>>> Subject: Re: [Zope3-dev] Important IFile bug!
>>>
>>> Roger Ineichen wrote:
>>>
>>>> Hi jim
>>>>
>>>>
>>>>> -----Original Message-----
>>>>> From: Jim Fulton [mailto:jim at zope.com] Sent: Friday, January 14, 
>>>>> 2005 5:30 PM
>>>>> To: dev at projekt01.ch
>>>>> Cc: zope3-dev at zope.org
>>>>> Subject: Re: [Zope3-dev] Important IFile bug!
>>>>>
>>>>> 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.
>>>>
>>>>
>>>>
>>>> This whould mean we change the IFile implementation?
>>>
>>>
>>> IFile should be changes to use a mime field.
>>>
>>>
>>>> Or can we Implement IMime with the attribute
>>>> contentType?
>>>
>>>
>>> We should define a mime data type and provide a field
>>> and widget to support it.
>>>
>>>
>>>> like:
>>>>
>>>> class IMime(Interface):
>>>>
>>>>  contentType = BytesLine(
>>>>        title = _(u'Content Type'),
>>>>        description=_(u'[...].'),
>>>>        default='',
>>>>        required=False,
>>>>        missing_value=''
>>>>        )
>>>>
>>>> class IFile(IIMime):
>>>>
>>>>  data = FileData(*) (
>>>>        title=_(u'Data'),
>>>>        description=_(u'[...]'),
>>>>        default='',
>>>>        missing_value='',
>>>>        required=False,
>>>>        )
>>>>
>>>> (*)The field FileData will replace the Bytes field and validate 
>>>> Bytes and FileChunk.
>>>
>>>
>>> No
>>>
>>> class IMime(Interface):
>>>
>>>     data = ...
>>>
>>>     contentType = ...
>>>
>>>     encoding = ...
>>>
>>> class IFile(Interface):
>>>
>>>    def open(mode='r'):
>>>        # return a file-like object for reading or updating the
>>>        # file value
>>>
>>>    # For backward compatibility, a deprecated data attr
>>>    data = ... # as is now
> 
> 
> Waaaaaaa, I got that wrong! Waaaaa waaaa waaaaa.
> (I edited the wrong interface.)
> 
> Sorry, This should have been:
> 
> class IMime(Interface):
> 
>      def open(mode='r'):
>         # return a file-like object for reading or updating the
>         # file value
> 
>      contentType = ...
> 
>      encoding = ...
> 
> class IFile(Interface):
> 
>     contents = Mime(...)
> 
>     # For backward compatibility, a deprecated data attr
>     data = ... # as is now
> 
> 
> 
>>
>>
>> And the class File looks like:
>>
>> Class File(Persistent):
>>
>>   implements(IFile, IMime)
>>
>>   def __init__(self, data='', contentType='', encoding=''):
>>       self.data = data
>>       self.contentType = contentType
>>       self.encoding = encoding
> 
> 
> 
> No:
> 
>     implements(IFile)
> 
>     def __init__(self, contents):
>         self.contents = contents
> 
>     def _getData(self):
>         return self.contents.open().read()
> 
>     def _setData(self, v):
>         self.contents.open('w').write(v)

Oops, I left out:

       data = property(_getData, _setData)

Jim


-- 
Jim Fulton           mailto:jim at zope.com       Python Powered!
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