Undefined method in my app. What's wrong?

Question

Hi there! I try blocking Ip addresses in my app like this - lifeonrails.org. I already have a module in /lib and model banned_ip.

Why I have this error below from views/banned_ips/index.html?

===My error:===

NoMethodError in Admin/banned_ips#index

*Showing app/views/admin/banned_ips/index.html.erb where line #9 raised:*

undefined method `banned?' for "127.0.0.1":String

Extracted source (around line #9):

6:     <th>Last_ip</th>
7:     <th>Date</th>
8:   </tr>
9: <% if request.remote_ip.banned? == true %>banned<% else %>ok<% end %>
10: <% for banned_ip in @banned_ips %>
11:   <tr>
12:     <td><%=h banned_ip.first_ip %></td>

---

===Module infrid.rb in /lib===

module Infrid
  class IPAddress
    include Comparable
    def initialize(address)
      @address = address
    end
    def split
      @address.split(‘.‘).map {|s| s.to_i }
    end
    def <=>(other)
      split <=> other.split
    end
    def to_s
      @address
    end
  end
end

---

===Model banned_ip:===

class BannedIp < ActiveRecord::Base
    @banned_ips # hash of ips and masks
    validates_presence_of :first_ip, :message =>"first address is needed"
    validates_presence_of :last_ip, :message =>"last address is needed"
    validates_format_of :first_ip, :with => REG_IP, :message => "is invalid (must be x.x.x.x where x is 0-255)", :if => Proc.new {|ar| !ar.first_ip.blank? }
    validates_format_of :last_ip, :with => REG_IP, :message => "is invalid (must be x.x.x.x where x is 0-255)", :if => Proc.new {|ar| !ar.last_ip.blank? }

    def self.banned?(ip)
      reload_banned_ips if @banned_ips.nil?
      begin
          ip = Infrid::IPAddress.new(ip)
          @banned_ips.each { |b|
            return true if ip.between?(b[0], b[1])
          }
      rescue
          logger.info "IP FORMAT ERROR"
          return true
      end
      false
    end
    def self.banned_ips
        reload_banned_ips if @banned_ips.nil?
        @banned_ips.collect {|b| b[0].to_s + ".." + b[1].to_s }.join"\n"
    end
    #keeps a cache of all banned ip ranges
    def self.reload_banned_ips
      r = connection.select_all("select first_ip, last_ip from banned_ips")
      if !r
        @banned_ips=[] 
      end
      @banned_ips = r.map {|item| [Infrid::IPAddress.new(item["first_ip"]),Infrid::IPAddress.new(item["last_ip"])] }
    end
end

Answer 1

That request.remote_ip returns the IP address as a String, and Strings do not have a banned? method. It looks like you want BannedIP.banned?(request.remote_ip).

Answer 2

Your problem is that you are trying to call banned? on a String, not on your BannedIp class. You have two solutions.

1. Replace the code to check for banned ip with BannedIp.banned?(request.remote_ip)
2. Patch in a method to the string class which calls the class method for you, which is in rails stype but less readable.

Need this here. (bug prevents code block from working)

class String
  def banned?
    BannedIp.banned?(self)
  end
end