[Zope] Re: Check uploaded file for valid contents

[Andreas Tille]

On Tue, 29 Oct 2002, Jerome Alet wrote:

> check the content_type of the object if possible.
>
> application/pdf is for ... PDF
Well, this is what I wanted to do but how to specify this.

I have a form

   <form name="Report" action="addReport" method="post" enctype="multipart/form-data">
     <input type="file" name="file" accept="application/pdf"><br />
     <input type="submit" value="New PDF file">
  </form>

and this is evaluated by the following Python Script addReport :

   response = container.REQUEST.RESPONSE
   form = container.REQUEST.form

   print form
   print form['file']
   # print form['file'].content_type

   container.manage_addProduct['ExtFile'].manage_addExtFile('iid', 'titel', 'descr', form['file'])

   return printed


This returns:

   {'file': <ZPublisher.HTTPRequest.FileUpload instance at 0x9e658cc>}
   <ZPublisher.HTTPRequest.FileUpload instance at 0x9e658cc>

If I uncomment the line in the script to get the content_type I get:

    Error Type: AttributeError
    Error Value: FileUpload instance has no attribute 'content_type'

If I search in the Zope source code for the class FileUpload I find the
available methods

              methods= ['close', 'fileno', 'flush', 'isatty',
                        'read', 'readline', 'readlines', 'seek',
                        'tell', 'truncate', 'write', 'writelines']

So I could use 'read' or 'readline' to parse the first bytes whether they
are valid PDF header, but I wonder if there is no more high level method
available.  If you think this information might be stored in the headers
attribute - forget it, it just consists of

    Content-Type: application/octet-stream

which is true for any uploaded file.

Kind regards

        Andreas.