Fail if it’s an invalid IP address (fixes #2)

lib/public_ip.rb

@@ -23,7 +23,7 @@ def get_ip(service: :random)
     else
       PublicIp::Service::Registry[service].ip
     end
-  rescue PublicIp::Service::TimedOut
+  rescue PublicIp::Service::TimedOut, PublicIp::Service::InvalidIpAddress
     tries -= 1
     if tries > 0 && service == :random
       retry

lib/public_ip/service/json_type.rb

@@ -9,9 +9,7 @@ def self.parse_json(_json_data)
         fail 'Not implemented'
       end
 
-      def self.ip
-        response = perform_request
-
+      def self.extract_ip(response)
         parse_json(JSON.parse(response.body.strip))
       end
     end

lib/public_ip/service/matched_expression.rb

@@ -5,9 +5,7 @@ class MatchedExpression < Simple
 
       attr_reader :match_regex
 
-      def self.ip
-        response = perform_request
-
+      def self.extract_ip(response)
         response.body.match(match_regex)[1].strip
       end
     end

lib/public_ip/service/parsed_html.rb

@@ -3,9 +3,11 @@ module Service
     class ParsedHTML < Simple
       extend PublicIp::Service::Registrable
 
-      def self.ip
-        response = perform_request
+      def self.parse_ip_address(_html)
+        fail 'Not implemented'
+      end
 
+      def self.extract_ip(response)
         parse_ip_address(response.body)
       end
     end

lib/public_ip/service/plain.rb

@@ -3,10 +3,8 @@ module Service
     class Plain < Simple
       extend PublicIp::Service::Registrable
 
-      def self.ip
-        response = perform_request
-
-        response.body.strip
+      def self.extract_ip(response)
+        response.body.strip.delete('"')
       end
     end
   end

lib/public_ip/service/simple.rb

@@ -1,13 +1,29 @@
 require 'net/http'
 require 'timeout'
 
+IPV4_REGEX = /(?:(?:25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])\.){3}(?:25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])/
+
 module PublicIp
   module Service
+    class InvalidIpAddress < StandardError; end
     class TimedOut < StandardError; end
+
     class Simple
       attr_reader :uri
       attr_reader :headers
 
+      def self.ip
+        response = perform_request
+
+        ip_address = extract_ip(response)
+
+        unless IPV4_REGEX.match(ip_address)
+          fail PublicIp::Service::InvalidIpAddress, "#{ip_address} is not a valid ip address"
+        end
+
+        ip_address
+      end
+
       def self.uri
         fail 'Not implemented'
       end