From: Jesper Olsen <Jesper@...>
Date: 2003-11-04T00:43:49+09:00
Subject: Re: CGI uses file size to distinguish between regular values and    files

I'm using the CGI module for file upload - I think it works,
it is just poorly documented.

At least it works for me - I use it mainly for uploading binary files (jpg images) - typically in the range 1k-100k bytes in size - but also larger.

Anyway, my code looks like this (upload.rbx)

cgi=CGI.new
if cgi.has_key?('image')
    image=cgi['image'][0].read
end

image is now a string representing the file that has been uploaded.
This only works for multipart forms however - ie. the HTML page
should look something like this:

    <form method="post" action="upload.rbx" ENCTYPE="multipart/form-data">
    <input type=hidden name=page value="upload">
    <input type=file size=20 name=image>
    ...

Or did I miss something?

Cheers
Jesper


Austin Ziegler <austin@halostatue.ca> wrote:
> On Mon, 3 Nov 2003 20:12:06 +0900, Dmitry Borodaenko wrote:
> > On Mon, Nov 03, 2003 at 02:29:08PM +0900, Simon Kitching wrote:
> >> I suspect that the fact that tempfiles are used by this module is a
> >> private implementation detail, ie something that users are not supposed
> >> to be aware of, or depend upon.
> > Why, you can always check if the parameter you've got _is_ a Tempfile,
> > and, if it is not, assume that it is small enough to be handled in core.
> >
> > Adopted from Samizdat source:
> 
> > if Tempfile === file then
> >   File.syscopy(file.path, upload)
> > else   # StringIO
> >   File.open(upload, 'w') {|f| f.write(file.read) }
> > end
> 
> > Did I miss something?
> 
> Why should I have to make that distinction in *my* code? I've got a Perl app
> that I plan to port over to Ruby at some point, and it allows file uploads
> (up to a couple megabytes in size). Indeed, the way that I deal with the
> file uploads never touches the filesystem from the perspective of my
> application (the file "string" goes directly into a MySQL database). If I
> have to step into my own filehandling, then I may not port this app to Ruby
> even though it's a fine candidate for it otherwise.
> 
> The library should provide me the raw data. If I decide something is a file
> and want to take some shortcuts with it, then the library can provide me
> additional information (e.g., CGI.tempfile?(parameter_index)) and
> functionality to access that implementation detail, but I should never
> *have* to make the distinction in my application code. Ever.
> 
> -austin
> --
> austin ziegler    * austin@halostatue.ca * Toronto, ON, Canada
> software designer * pragmatic programmer * 2003.11.03
>                                          * 09.35.55
> 
> 
>