Ruby bindings for existing FFI methods, plus eval_rule() (#188)

* Ruby binding

* use relative regorus crate in ruby instead of a published version, also cargo fmt

* remove unnecessary Cargo.toml, include the top level Cargo.lock in ruby gem

* ruby bindings continued- add eval_rule, fix _json methods, update README.md

also added rubocop-minitest and rubocop-rake, and added more test coverage

* update README.md to include Ruby bindings

Closes #191

Cargo.toml

@@ -5,6 +5,7 @@ members = [
     "bindings/python",
     "bindings/wasm",
     "bindings/java",
+    "bindings/ruby/ext/regorusrb",
 ]
 
 [package]

README.md

@@ -13,7 +13,7 @@ Regorus is also
   - *extensible* - Extend the Rego language by implementing custom stateful builtins in Rust.
     See [add_extension](https://github.com/microsoft/regorus/blob/fc68bf9c8bea36427dae9401a7d1f6ada771f7ab/src/engine.rs#L352).
     Support for extensibility using other languages coming soon.
-  - *polyglot* - In addition to Rust, Regorus can be used from *C*, *C++*, *C#*, *Golang*, *Java*, *Javascript* and *Python*.
+  - *polyglot* - In addition to Rust, Regorus can be used from *C*, *C++*, *C#*, *Golang*, *Java*, *Javascript*, *Python*, and *Ruby*.
     This is made possible by the excellent FFI tools available in the Rust ecosystem. See [bindings](#bindings) for information on how to use Regorus from different languages.
 
     To try out a *Javascript(WASM)* compiled version of Regorus from your browser, visit [Regorus Playground](https://anakrish.github.io/regorus-playground/).
@@ -90,6 +90,8 @@ Regorus can be used from a variety of languages:
 - *Javascript*: Regorus is compiled to WASM using [wasmpack](https://github.com/rustwasm/wasm-pack).
   See [bindings/wasm](https://github.com/microsoft/regorus/tree/main/bindings/wasm) for an example of using Regorus from nodejs.
   To try out a *Javascript(WASM)* compiled version of Regorus from your browser, visit [Regorus Playground](https://anakrish.github.io/regorus-playground/).
+- *Ruby*: Ruby bindings are developed using [magnus](https://github.com/matsadler/magnus).
+  See [bindings/ruby](https://github.com/microsoft/regorus/tree/main/bindings/ruby).
 
 To avoid operational overhead, we currently don't publish these bindings to various repositories.
 It is straight-forward to build these bindings yourself.

bindings/ruby/.gitignore

@@ -0,0 +1,14 @@
+/.bundle/
+/.yardoc
+/_yardoc/
+/coverage/
+/doc/
+/pkg/
+/spec/reports/
+/tmp/
+*.bundle
+*.so
+*.o
+*.a
+mkmf.log
+target/

bindings/ruby/.rubocop.yml

@@ -0,0 +1,29 @@
+require:
+  - rubocop-minitest
+  - rubocop-rake
+
+AllCops:
+  TargetRubyVersion: 3.0
+  NewCops: enable
+
+Layout/LineLength:
+  Max: 180
+
+Lint/EmptyClass:
+  Enabled: false
+
+Metrics/ClassLength:
+  Exclude:
+    - 'test/**/*.rb'
+
+Metrics/MethodLength:
+  Enabled: false
+
+Style/StringLiterals:
+  EnforcedStyle: double_quotes
+
+Style/StringLiteralsInInterpolation:
+  EnforcedStyle: double_quotes
+
+Style/WordArray:
+  Enabled: false

bindings/ruby/.tool-versions

@@ -0,0 +1 @@
+ruby 3.3.0

bindings/ruby/CHANGELOG.md

@@ -0,0 +1,5 @@
+## [Unreleased]
+
+## [0.1.0] - 2024-03-29
+
+- Initial release

bindings/ruby/Gemfile

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+source "https://rubygems.org"
+
+# Specify your gem's dependencies in regorusrb.gemspec
+gemspec
+
+# These gems are required for local development and testing,
+# but won't be included in the published gem
+gem "minitest", "~> 5.16"
+gem "rake", "~> 13.0"
+gem "rake-compiler"
+gem "rb_sys", "~> 0.9.63"
+gem "rubocop", "~> 1.62", require: false
+gem "rubocop-minitest", require: false
+gem "rubocop-rake", require: false

bindings/ruby/Gemfile.lock

@@ -0,0 +1,61 @@
+PATH
+  remote: .
+  specs:
+    regorusrb (0.1.0)
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    ast (2.4.2)
+    json (2.7.1)
+    language_server-protocol (3.17.0.3)
+    minitest (5.22.3)
+    parallel (1.24.0)
+    parser (3.3.0.5)
+      ast (~> 2.4.1)
+      racc
+    racc (1.7.3)
+    rainbow (3.1.1)
+    rake (13.1.0)
+    rake-compiler (1.2.7)
+      rake
+    rb_sys (0.9.90)
+    regexp_parser (2.9.0)
+    rexml (3.2.6)
+    rubocop (1.62.1)
+      json (~> 2.3)
+      language_server-protocol (>= 3.17.0)
+      parallel (~> 1.10)
+      parser (>= 3.3.0.2)
+      rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 1.8, < 3.0)
+      rexml (>= 3.2.5, < 4.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (>= 2.4.0, < 3.0)
+    rubocop-ast (1.31.2)
+      parser (>= 3.3.0.4)
+    rubocop-minitest (0.35.0)
+      rubocop (>= 1.61, < 2.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+    rubocop-rake (0.6.0)
+      rubocop (~> 1.0)
+    ruby-progressbar (1.13.0)
+    unicode-display_width (2.5.0)
+
+PLATFORMS
+  ruby
+  x86_64-linux
+
+DEPENDENCIES
+  minitest (~> 5.16)
+  rake (~> 13.0)
+  rake-compiler
+  rb_sys (~> 0.9.63)
+  regorusrb!
+  rubocop (~> 1.62)
+  rubocop-minitest
+  rubocop-rake
+
+BUNDLED WITH
+   2.5.7

bindings/ruby/LICENSE.txt

@@ -0,0 +1 @@
+../../LICENSE

bindings/ruby/README.md

@@ -0,0 +1,95 @@
+# Regorusrb
+
+**Regorus** is
+
+  - *Rego*-*Rus(t)*  - A fast, light-weight [Rego](https://www.openpolicyagent.org/docs/latest/policy-language/)
+   interpreter written in Rust.
+  - *Rigorous* - A rigorous enforcer of well-defined Rego semantics.
+
+## Installation
+
+Regorus can be used in Ruby by configuring bundler to build from the remote git source.
+
+Use the bundler CLI to add the gem from remote git source:
+`
+bundle add regorus --git 'https://github.com/microsoft/regorus/tree/main/bindings/ruby'
+`
+
+or manually edit your gemfile to include the following
+`
+gem "regorus", git: "https://github.com/microsoft/regorus/tree/main/bindings/ruby"
+`
+
+It is not yet available in rubygems.
+
+See [Repository](https://github.com/microsoft/regorus).
+
+To build this gem locally without bundler,
+
+`rake build`
+
+then to install the gem and build the native extensions
+
+`gem install --local ./pkg/regorusrb-0.1.0.gem`
+
+## Usage
+
+```ruby
+require "regorus"
+
+engine = Regorus::Engine.new
+
+engine.add_policy_from_file('../../tests/aci/framework.rego')
+engine.add_policy_from_file('../../tests/aci/api.rego')
+engine.add_policy_from_file('../../tests/aci/policy.rego')
+
+
+# can be strings or symbols
+data = {
+  metadata: {
+    devices: {
+      "/run/layers/p0-layer0": "1b80f120dbd88e4355d6241b519c3e25290215c469516b49dece9cf07175a766",
+      "/run/layers/p0-layer1": "e769d7487cc314d3ee748a4440805317c19262c7acd2fdbdb0d47d2e4613a15c",
+      "/run/layers/p0-layer2": "eb36921e1f82af46dfe248ef8f1b3afb6a5230a64181d960d10237a08cd73c79",
+      "/run/layers/p0-layer3": "41d64cdeb347bf236b4c13b7403b633ff11f1cf94dbc7cf881a44d6da88c5156",
+      "/run/layers/p0-layer4": "4dedae42847c704da891a28c25d32201a1ae440bce2aecccfa8e6f03b97a6a6c",
+      "/run/layers/p0-layer5": "fe84c9d5bfddd07a2624d00333cf13c1a9c941f3a261f13ead44fc6a93bc0e7a"
+    }
+  }
+}
+
+engine.add_data(data)
+input = {
+  "containerID": "container0",
+  "layerPaths": [
+    "/run/layers/p0-layer0",
+    "/run/layers/p0-layer1",
+    "/run/layers/p0-layer2",
+    "/run/layers/p0-layer3",
+    "/run/layers/p0-layer4",
+    "/run/layers/p0-layer5"
+  ],
+  "target": "/run/gcs/c/container0/rootfs"
+}
+
+engine.set_input(input)
+
+# Evaluate a specife rule
+rule_results = engine.eval_rule('data.framework.mount_overlay')
+puts rule_results # { "allowed" => true, "metadata" => [...]}
+
+# Or evalute a full policy document
+query_results = engine.eval_query('data.framework')
+puts query_results[:result][0]
+
+# Query results can can also be returned as JSON strings instead of Ruby Hash structure
+results_json = engine.eval_query_as_json('data.framework.mount_overlay=x')
+puts results_json
+```
+
+## Development
+
+After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake test` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.
+
+To install this gem onto your local machine, run `bundle exec rake install`. To release a new version, update the version number in `version.rb`, and then run `bundle exec rake release`, which will create a git tag for the version, push git commits and the created tag, and push the `.gem` file to [rubygems.org](https://rubygems.org).
+

bindings/ruby/Rakefile

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+require "bundler/gem_tasks"
+require "minitest/test_task"
+
+Minitest::TestTask.create
+
+require "rubocop/rake_task"
+
+RuboCop::RakeTask.new
+
+require "rb_sys/extensiontask"
+
+desc "build the .gem file, including native extensions, according to the .gemspec"
+task build: :compile
+
+GEMSPEC = Gem::Specification.load("regorusrb.gemspec")
+
+RbSys::ExtensionTask.new("regorusrb", GEMSPEC) do |ext|
+  ext.lib_dir = "lib/regorusrb"
+end
+
+task default: %i[compile test rubocop]

bindings/ruby/bin/console

@@ -0,0 +1,11 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require "bundler/setup"
+require "regorus"
+
+# You can add fixtures and/or initialization code here to make experimenting
+# with your gem easier. You can also use a different console, if you like.
+
+require "irb"
+IRB.start(__FILE__)

bindings/ruby/bin/setup

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+set -euo pipefail
+IFS=$'\n\t'
+set -vx
+
+bundle install
+
+# Do any other automated setup that you need to do here

bindings/ruby/ext/regorusrb/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "regorusrb"
+version = "0.1.0"
+edition = "2021"
+description = "Ruby bindings for Regorus - a fast, lightweight Rego interpreter written in Rust"
+publish = false
+
+[lib]
+crate-type = ["cdylib"]
+path = "src/lib.rs"
+
+[dependencies]
+magnus = { version = "0.6.2" }
+regorus = { path = "../../../.." }
+serde_json = "1.0.115"
+serde_magnus = "0.8.1"

bindings/ruby/ext/regorusrb/extconf.rb

@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+require "mkmf"
+require "rb_sys/mkmf"
+
+create_rust_makefile("regorusrb/regorusrb")