raising RateLimitError then 429 status code appears.

lib/ipinfo_io.rb

@@ -1,25 +1,30 @@
 # frozen_string_literal: true
 
 require "ipinfo_io/version"
+require 'ipinfo_io/errors'
 require 'faraday'
 require 'json'
 
 module IpinfoIo
+  RATE_LIMIT_MESSAGE = "To increase your limits, please review our paid plans at https://ipinfo.io/pricing"
+  HOST = 'ipinfo.io'
+
   class << self
     def lookup(ip=nil)
-      response = Faraday.get("https://ipinfo.io/#{ip}") do |req|
-        default_header.each_pair do |key, value|
+      response = Faraday.get("https://#{HOST}/#{ip}") do |req|
+        default_headers.each_pair do |key, value|
           req.headers[key] = value
         end
       end
 
+      raise RateLimitError.new(RATE_LIMIT_MESSAGE) if response.status.eql?(429)
+
       JSON.parse(response.body)
     end
 
-
     private
 
-    def default_header
+    def default_headers
         {
           'User-Agent' => "ruby/#{::IpinfoIo::VERSION}",
           'Accept' => 'application/json'

lib/ipinfo_io/errors.rb

@@ -0,0 +1,3 @@
+module IpinfoIo
+  class RateLimitError < StandardError; end
+end

test/ipinfo_io_test.rb

@@ -9,6 +9,12 @@ def test_that_it_has_a_version_number
     refute_nil ::IpinfoIo::VERSION
   end
 
+  def test_rate_limit_error
+    stub_request(:get, 'https://ipinfo.io').to_return(body:'', status: 429)
+    error = assert_raises(IpinfoIo::RateLimitError) { IpinfoIo.lookup }
+    assert_equal "To increase your limits, please review our paid plans at https://ipinfo.io/pricing", error.message
+  end
+
   def test_lookup_without_arg
     expected = {
       "ip" => "110.171.151.183",

test/test_helper.rb

@@ -4,7 +4,7 @@
 require 'minitest/autorun'
 require 'minitest/reporters'
 require 'minitest-vcr'
-require 'webmock'
+require 'webmock/minitest'
 
 Minitest::Reporters.use!(
   Minitest::Reporters::SpecReporter.new