Apply rate limiting PR from avidw (samsymons#24)

README.md

@@ -46,8 +46,6 @@ subreddits = client.subscribed_subreddits
 
 Using RedditKit.rb at the module level allows you to use a single account without having to keep track of RedditKit::Client instances. Working at the instance method level makes it possible to use multiple accounts at once, with one client object per account.
 
-> RedditKit.rb doesn't have any built-in rate limiting. reddit's API rules require that you make no more than 30 requests per minute and try to avoid requesting the same page more than once every 30 seconds. You can read up on the API rules [on their wiki page](https://github.com/reddit/reddit/wiki/API).
-
 ### Authentication
 
 ```ruby

lib/redditkit/client.rb

@@ -1,6 +1,7 @@
 require 'faraday'
 require 'redditkit/error'
 require 'redditkit/version'
+require 'redditkit/rate_limit'
 require 'redditkit/client/account'
 require 'redditkit/client/apps'
 require 'redditkit/client/captcha'
@@ -50,6 +51,7 @@ class Client
     attr_accessor :authentication_endpoint
     attr_accessor :user_agent
     attr_accessor :middleware
+    attr_accessor :rate_limit
 
     def initialize(username = nil, password = nil)
       @username = username
@@ -84,6 +86,10 @@ def middleware
 
     private
 
+    def rate_limit
+      @rate_limit ||= RedditKit::RateLimit.new
+    end
+
     def get(path, params = nil)
       request(:get, path, params, connection)
     end
@@ -105,6 +111,8 @@ def delete_path(path, params = nil)
     end
 
     def request(method, path, parameters = {}, request_connection)
+      rate_limit.wait
+
       if signed_in?
         request = authenticated_request_configuration(method, path, parameters)
         request_connection.send(method.to_sym, path, parameters, &request).env

lib/redditkit/rate_limit.rb

@@ -0,0 +1,19 @@
+module RedditKit
+
+  # The class to rate-limit requests to reddit.
+  class RateLimit
+    # Time the last request was made.
+    attr_reader :last_request
+
+    def initialize
+      @last_request = Time.at(0)
+    end
+
+    # Sleep until a given number of seconds have passed since the last request
+    def wait(gap = 2)
+      wait_time = @last_request + gap - Time.now
+      sleep(wait_time) if wait_time > 0
+      @last_request = Time.now
+    end
+  end
+end