add lets encrypt gem

db/migrate/20220409143030_create_letsencrypt_certificates.rb

@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+# :nodoc:
+class CreateLetsencryptCertificates < ActiveRecord::Migration[7.0]
+  def change
+    create_table :letsencrypt_certificates do |t|
+      t.string   :domain
+      t.text     :certificate, limit: 65535
+      t.text     :intermediaries, limit: 65535
+      t.text     :key, limit: 65535
+      t.datetime :expires_at
+      t.datetime :renew_after
+      t.string   :verification_path
+      t.string   :verification_string
+
+      t.index    :domain
+      t.index    :renew_after
+      t.timestamps
+    end
+  end
+end