add global rate limit tracking

Author: josler

lib/intercom.rb

@@ -36,6 +36,7 @@ module Intercom
   @current_endpoint = nil
   @app_id = nil
   @app_api_key = nil
+  @rate_limit_details = {}
 
   def self.app_id=(app_id)
     @app_id = app_id
@@ -48,10 +49,19 @@ def self.app_id
   def self.app_api_key=(app_api_key)
     @app_api_key = app_api_key
   end
+
   def self.app_api_key
     @app_api_key
   end
 
+  def self.rate_limit_details=(rate_limit_details)
+    @rate_limit_details = rate_limit_details
+  end
+
+  def self.rate_limit_details
+    @rate_limit_details
+  end
+
   # This method is obsolete and used to warn of backwards incompatible changes on upgrading
   def self.api_key=(val)
     raise ArgumentError, "#{compatibility_warning_text} #{compatibility_workaround_text} #{related_docs_text}"

lib/intercom/request.rb

@@ -61,6 +61,7 @@ def execute(target_base_url=nil)
         client(base_uri).start do |http|
           begin
             response = http.request(net_http_method)
+            set_rate_limit_details(response)
             decoded = decode(response['content-encoding'], response.body)
             unless decoded.strip.empty?
               parsed_body = JSON.parse(decoded)
@@ -77,6 +78,14 @@ def execute(target_base_url=nil)
       end
     end
 
+    def set_rate_limit_details(response)
+      rate_limit_details = {}
+      rate_limit_details[:limit] = response['X-RateLimit-Limit'].to_i if response['X-RateLimit-Limit']
+      rate_limit_details[:remaining] = response['X-RateLimit-Remaining'].to_i if response['X-RateLimit-Remaining']
+      rate_limit_details[:reset_at] = Time.at(response['X-RateLimit-Reset'].to_i) if response['X-RateLimit-Reset']
+      Intercom.rate_limit_details = rate_limit_details
+    end
+
     def decode(content_encoding, body)
       return body if (!body) || body.empty? || content_encoding != 'gzip'
       Zlib::GzipReader.new(StringIO.new(body)).read