1 files changed, 33 insertions, 0 deletions
diff --git a/app/validators/email_validator.rb b/app/validators/email_validator.rb
new file mode 100644
index 0000000..4191907
--- /dev/null
+++ b/app/validators/email_validator.rb
@@ -0,0 +1,33 @@
+# SPDX-FileCopyrightText: 2020 IN COMMON Collective <collective@incommon.cc>
+#
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+# frozen_string_literal: true
+
+# = Email Validator =
+#
+# In order to be considered valid, value must be:
+#
+# - a valid Email URI
+# - parsable as an URI
+# - have a hostname
+# - have a valid public TLD
+#
+class EmailValidator < ActiveModel::EachValidator
+  def validate_each(record, attribute, value)
+    unless valid_email_address?(value)
+      record.errors[attribute] << (options[:message] || 'is an invalid email address')
+    end
+  end
+
+  private
+
+  def valid_email_address?(value)
+    uri = URI.parse("mailto:#{value}")
+    uri.is_a?(URI::MailTo) &&
+      uri.to == value &&
+      IANA::TLD.valid?(value.split('@', 2).last.split('.').compact.last)
+  rescue URI::InvalidURIError, URI::InvalidComponentError
+    false
+  end
+end