Re^2: Problem uploading file data using CGI

Thanks for the quick reply.

1. The data as it comes into the web server is

Content-Type: application/octet-stream

and that is what is causing the problem because it really needs to be multipart/form-data. CGI.pm is supposed to be able to read application/octet-stream (and, I'm sure, does) but I'm obviously doing something wrong.

2. I think that I've mislead you with regard to the code I'm using to try and extract the data. In both cases it was cut and pasted from the man pages because I'd changed the code in the program to many different things. Here is what I've actually used:-


############  First Attempt

$data = $Data->param('POSTDATA');

open(FILE,">/tmp/$Filename");
print FILE $data;
close(FILE);

##########  Alternative attempt

$handle = $Data->upload($Mtfilename);
if (defined $handle) {
        $io_handle = $handle->handle;
        open(FILE,">/tmp/$Filename");
        while ($bytesread = $io_handle->read($buffer,1024)) {
                print FILE $buffer;
        }
        close(FILE);
}
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Re^3: Problem uploading file data using CGI by tobyink (Canon) on Mar 17, 2013 at 23:36 UTC
"1. The data as it comes into the web server is `Content-Type: application/octet-stream`" No, it doesn't. You're not looking at the real HTTP headers. A multipart/form-data HTTP message has an uber-header at the top, and then each form field has its own set of mini-headers. The `Content-Type: application/octet-stream` header you posted is from the file field's mini-headers. The uber-headers will say `Content-Type: multipart/form-data`. A full multipart/form-data HTTP request might look something like this: `POST /handler.cgi HTTP/1.1 Host: http://www.example.com/ Content-Type: multipart/form-data; boundary=XYZ --XYZ Content-Disposition: form-data; name="title" Picture of Camel --XYZ Content-Disposition: form-data; name="upload" Content-Type: image/jpeg ... some binary data ... --XYZ--` [download] The kind of form that might result in that request is: `<form action="http://www.example.com/handler.cgi" method="post" enctype="multipart/form-data"> <fieldset> <legend>Image upload</legend> <label>Image <input name="title"></label><br> <label>File <input name="upload" type="file"></label> <input type="submit"> </fieldset> </form>` [download] And my advice to check the return value of `open()` still stands. `package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name`	[reply] [d/l] [select]

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Re^3: Problem uploading file data using CGI
by tobyink (Canon) on Mar 17, 2013 at 23:36 UTC

"1. The data as it comes into the web server is Content-Type: application/octet-stream"

No, it doesn't. You're not looking at the real HTTP headers. A multipart/form-data HTTP message has an uber-header at the top, and then each form field has its own set of mini-headers.

The Content-Type: application/octet-stream header you posted is from the file field's mini-headers. The uber-headers will say Content-Type: multipart/form-data.

A full multipart/form-data HTTP request might look something like this:

POST /handler.cgi HTTP/1.1
Host: http://www.example.com/
Content-Type: multipart/form-data; boundary=XYZ

--XYZ
Content-Disposition: form-data; name="title"

Picture of Camel
--XYZ
Content-Disposition: form-data; name="upload"
Content-Type: image/jpeg

... some binary data ...
--XYZ--
[download]

The kind of form that might result in that request is:

<form action="http://www.example.com/handler.cgi"
      method="post"
      enctype="multipart/form-data">
  <fieldset>
    <legend>Image upload</legend>
    <label>Image <input name="title"></label><br>
    <label>File <input name="upload" type="file"></label>
    <input type="submit">
  </fieldset>
</form>
[download]

And my advice to check the return value of open() still stands.

package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name

[reply]
[d/l]
[select]