Parse dhall, convert to json, flatten to plain object

zhulik · Jan 1, 2023 · 05e2793 · 05e2793
1 parent 7871d24
commit 05e2793
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Showing 7 changed files with 127 additions and 7 deletions.
diff --git a/bin/console b/bin/console
@@ -4,12 +4,5 @@
 require "bundler/setup"
 require "dotcrypt"
 
-# 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.
-
-# (If you use this, don't forget to add pry to your Gemfile!)
-# require "pry"
-# Pry.start
-
 require "irb"
 IRB.start(__FILE__)
diff --git a/bin/dhall b/bin/dhall
@@ -0,0 +1,13 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require "bundler/setup"
+require "dotcrypt"
+
+config = Dotcrypt::Dhall.load(File.read(ARGV.first))
+
+# puts(JSON.pretty_generate(config))
+
+puts(JSON.pretty_generate(Dotcrypt::Flattener.call(config)))
+
+# puts(Dotcrypt::Compiler.(config))
diff --git a/example.dhall b/example.dhall
@@ -0,0 +1,19 @@
+let some_variable = "some value"
+in  {
+      some_string = some_variable,
+      some_record = {
+        some_string = some_variable,
+        some_naturals = [1,2,3],
+        some_doubles = [1.2, 2.3],
+        some_strings = ["value1", "value2"],
+        -- some_records = [
+        --   {
+        --     key = "value"
+        --   },
+        --   {
+        --     key = "value"
+        --   }
+        -- ],
+        some_nil = None
+      }
+    }
diff --git a/lib/dotcrypt.rb b/lib/dotcrypt.rb
@@ -1,7 +1,11 @@
 # frozen_string_literal: true
 
+require "json"
+
 require "zeitwerk"
 
+require "dhall"
+
 loader = Zeitwerk::Loader.for_gem
 
 loader.setup

diff --git a/lib/dotcrypt/dhall.rb b/lib/dotcrypt/dhall.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module Dotcrypt::Dhall
+  using Dotcrypt::Dhall::AsHash
+
+  class << self
+    def load(dhall)
+      Dhall.load(dhall).sync.as_hash
+    end
+  end
+end
diff --git a/lib/dotcrypt/dhall/as_hash.rb b/lib/dotcrypt/dhall/as_hash.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+module Dotcrypt::Dhall::AsHash
+  refine Dhall::Record do
+    def as_hash(*)
+      to_h.transform_values(&:as_hash)
+    end
+  end
+
+  refine Dhall::List do
+    def as_hash(*)
+      to_a.map(&:as_hash)
+    end
+  end
+
+  refine Dhall::Text do
+    def as_hash(*)
+      to_s
+    end
+  end
+
+  refine Dhall::Natural do
+    def as_hash(*)
+      to_i
+    end
+  end
+
+  refine Dhall::Double do
+    def as_hash(*)
+      to_f
+    end
+  end
+
+  refine Dhall::Builtins::None do
+    def as_hash(*)
+      nil
+    end
+  end
+end
diff --git a/lib/dotcrypt/flattener.rb b/lib/dotcrypt/flattener.rb
@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+class Dotcrypt::Flattener
+  SCALARS = [String, Numeric, NilClass].freeze
+
+  def self.call(...) = new(...).call
+
+  def initialize(config, prefixes: [], accumulator: {}, separator: "_")
+    @config = config
+    @prefixes = prefixes
+    @accumulator = accumulator
+    @separator = separator
+  end
+
+  def call
+    case config
+    when *SCALARS then save(@config)
+    when Hash then config.each { |k, v| self.class.call(v, prefixes: prefixes + [k], accumulator:, separator:) }
+    when Array then flatten_array
+    else raise TypeError, "unknown type: #{config.class}"
+    end
+
+    accumulator
+  end
+
+  private
+
+  attr_reader :config, :prefixes, :accumulator, :separator
+
+  def flatten_array
+    raise TypeError, "only arrays of scalars are allowed, given: #{config}" unless config.all? { scalar?(_1) }
+
+    save(config.to_json)
+  end
+
+  def scalar?(value) = SCALARS.any? { value.is_a?(_1) }
+
+  def path = @prefixes.join(@separator)
+
+  def save(value) = @accumulator[path] = value
+end