Hi!
I need a little help for my Maplat webserver project: To automate some processes i like to give the user the opportunity to write simple embedded script code. This scripts should be able to do math, string matching and change some given data structures - but nothing more. No file access, no access to the host script (written in perl).
This interpreter would be run within a perl script, get the data structures defined by that script and after the interpreter finished (or timed out) the results would be used in the perl script.
Here's a (rather stupid, i admit) example pseudo code how it could be used in a webmail system:
// Forward mail to private account on weekend
if weekday > 5 then
email.reciever = "private@example.com"
exit;
end
if email.subject has "TEST" then
email.mailbox = "testmails"
else if email.sender == "boss@example.com"
email.mailbox = "bigboss"
else
email.mailbox = "trash"
end
I looked into Lua::API, but i'm not sure how to safely sandbox that. I read some Lua documentation, but i'm none the wiser...
Any ideas how to do that?
Rene
UPDATE
Managed to translate http://lua-users.org/wiki/SimpleLuaApiExample into a simple Lua::API script.
test.lua:
x = 0
for i = 1, #foo do
x = x + foo[i]
end
return x
test.pl:
use strict;
use warnings;
use Lua::API;
my $L = Lua::API::State->new;
my $status = $L->loadfile("test.lua");
if($status) {
die "Failed to load file: " . $L->tostring(-1);
}
$L->newtable;
for(my $i = 1; $i <= 5; $i++) {
$L->pushnumber($i);
$L->pushnumber($i*2);
$L->rawset(-3);
}
$L->setglobal("foo");
my $result = $L->pcall(0, Lua::API::MULTRET, 0);
if($result) {
die "Failed to execute file: " . $L->tostring(-1);
}
my $sum = $L->tonumber(-1);
print "Script returned $sum\n";
$L->pop(1);
$L->close;
This still needs a lot of work though, but i see a (very dim) light at the end of the (very long) tunnel.
Don't use '#ff0000':
use Acme::AutoColor; my $redcolor = RED();
All colors subject to change without notice.
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