not sure if LWP::Useragent will fetch the file contain itself

Yes, it will. Try

#!/usr/bin/perl
use strict;
use warnings;
use LWP::UserAgent;
use JSON;
use FindBin qw($Bin);;

my $token = '';
my $url   = 'http://';
my $attributes = encode_json ({ 
   name => "test.txt", 
   parent => { id => 0 }
});

my $ua  = LWP::UserAgent->new;
my $response = $ua->post($url,
   Content_Type => 'form-data',
   Authorization => "Bearer $token",
   Content => [
      attributes => $attributes,
      file       => [ "$Bin/test.txt" ],
   ],
);

if ($response->is_success) {
  print $response->decoded_content; 
} else {
  die $response->status_line;
}

[download]
poj

In reply to Re^5: Post using LWP useragent curl post request to useragent request by poj
in thread Post using LWP useragent curl post request to useragent request by smarthacker67

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