wip: extract tarball downloading into separate command

lib/commit.rb

@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require 'yaml'
+
+class Commit
+  attr_reader :sha
+  attr_reader :time
+
+  def initialize(sha:, time:)
+    @sha = sha
+    @time = time
+  end
+
+  def sha_short
+    sha[0..6]
+  end
+
+  def to_hash
+    {
+      'sha' => sha,
+      'sha_short' => sha_short,
+      'time' => time
+    }
+  end
+
+  def to_yaml
+    to_hash.to_yaml
+  end
+end