The next version of @nlnetlabs 's scripting language Roto (to be released sometime in December) will include a much-requested feature: lists! Below is a small example of lists in action, showcasing how easy it is to pass them to and from a Roto script. It will print `Result: [0, 1, 2, 3, 4, 5]`.

I'd like to take a moment to explain why lists were so hard to include in Roto in a thread!

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#rust #rustlang #roto

The next version of @nlnetlabs 's scripting language Roto (to be released sometime in December) will include a much-requested feature: lists! Below is a small example of lists in action, showcasing how easy it is to pass them to and from a Roto script. It will print `Result: [0, 1, 2, 3, 4, 5]`.

I'd like to take a moment to explain why lists were so hard to include in Roto in a thread!

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#rust #rustlang #roto

roto - The strongly-typed, compiled #embedded scripting language for #Rust, used by Rotonda

Introducing #Roto: A Compiled Scripting Language for Rust (May 2025):
https://blog.nlnetlabs.nl/introducing-roto-a-compiled-scripting-language-for-rust/

Repo:
https://github.com/NLnetLabs/roto

This looks awesome! I love strongly typed scripting languages!

And the fact that it integrates with Rust so seamlessly... ✨

#RustLang #ProgrammingLanguage #Scripting #ScriptingLanguage

roto - The strongly-typed, compiled #embedded scripting language for #Rust, used by Rotonda

Introducing #Roto: A Compiled Scripting Language for Rust (May 2025):
https://blog.nlnetlabs.nl/introducing-roto-a-compiled-scripting-language-for-rust/

Repo:
https://github.com/NLnetLabs/roto

This looks awesome! I love strongly typed scripting languages!

And the fact that it integrates with Rust so seamlessly... ✨

#RustLang #ProgrammingLanguage #Scripting #ScriptingLanguage

Another reason the previous ASN->string->AhoCorasick thing doesn't quite work is because the pattern matching is a partial match. Thankfully, there's a StringList type I export to #roto, with a .contents() method, so:

let asn = ASN
  .as_asn_matcher()?
  .lookup(request.header("x-forwarded-for"))
  .to_string();
if BANNED_ASNS.contains(asn) {
  return garbage("banned-asn");
}

...this will work correctly, though, it will be slower than an AhoCorasick match if the list is longer than about a dozen ASNs. And the string conversion is comparatively expensive.

#iocaine

From nothing to running iocaine + Caddy with ai.robots.txt's robots.json and a few metrics as a starting point.

Contains #Roto, #Lua, and #Fennel - and a few tests too, for each.

I'm on a bit of a roll lately, and have released #iocaine version 2.4.0 just a few moments ago.

This does not bring that many significant changes as 2.3.0 did, but it does introduce #Lua and #Fennel as languages you can script its decision making with, on top of #Roto, which was introduced in 2.2.0.

While these languages run slower than Roto, they're still very fast, and are not going to be a bottleneck - they do provide a more familiar language to write the decision making in!

Oh, and metrics can now be persisted across restarts.

In other #iocaine news, I'm doing some final polishing on #Lua scripting support, to make it as convenient as #Roto.

Right now, there's a differenc between how Lua and Roto scripts are loaded: with Roto, one needs to give a path to a directory, and pkg.roto will be loaded from there, and any imports will be relative to that directory.

With Lua, one gives iocaine a file path, and - currently - needs to set up the package.path search path manually.

So here's what I'll do: I'll make iocaine require a directory for Lua too, and it will add it to package.path, and will require("main"). The required module will also have to return a table with at least a decide key, and an optional run_tests key. This will simplify finding the functions to run, and will greatly reduce the number of special cases.

Today, I'm writing tests. Originally, I planned to write a bunch of tests in Rust to exercise the request handlers, but that felt like a huge pain in the backside, and would've involved a lot of repetition and boilerplate.

Then, I figured: I'll write the tests in #Roto and #Lua! Test the things from that side. Much less boilerplate, but still a lot of repetition.

Instead, I'll be writing a test suite to verify the decisions of a request handler. I'll run it for both engines, #Roto and #Lua. I will still have to write the scripts twice, but I will only write the verification once.