fix dependency

app/models/link.rb

@@ -1,3 +1,5 @@
+require 'net/http'
+
 class Link < ApplicationRecord
   belongs_to :link_category
   has_rich_text :description_html
@@ -5,7 +7,7 @@ class Link < ApplicationRecord
   validates :url, :text, presence: true
   validate :check_url
   validate :valid_url
-  
+
   before_validation :ensure_absolute_url
 
   def ok?
@@ -14,21 +16,21 @@ class Link < ApplicationRecord
 
   private
 
-  USER_AGENT = "Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0"
+  USER_AGENT = 'Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0'
 
   def check_url(input = url, add_error = true)
     response = begin
-      Net::HTTP.get_response(URI.parse(input), "User-Agent": USER_AGENT) 
+      Net::HTTP.get_response(URI.parse(input), 'User-Agent': USER_AGENT)
     rescue Socket::ResolutionError
       errors.add(:url, :invalid) if add_error
       return false
     end
-      
+
     case response
     when Net::HTTPSuccess
       self.last_check_at = Time.zone.now
       self.fail_count = 0
-      
+
       true
     when Net::HTTPRedirection
       check_url(response[:location])
@@ -42,10 +44,10 @@ class Link < ApplicationRecord
   end
 
   def ensure_absolute_url
-    self.url = "https://#{self.url}" unless self.url.match?(%r{https{0,1}://.*})
+    self.url = "https://#{url}" unless url.match?(%r{https{0,1}://.*})
   end
 
   def valid_url
-    errors.add(:url, :invalid) unless url.match /\A#{URI::regexp(['http', 'https'])}\z/
+    errors.add(:url, :invalid) unless url.match(/\A#{URI::DEFAULT_PARSER.make_regexp(%w[http https])}\z/)
   end
 end