work on #2693 Separate API Limits by Writes/Reads

app/controllers/application_controller.rb

@@ -41,7 +41,7 @@ protected
   
   def api_check
     if request.format.to_s =~ /\/json|\/xml/ || params[:controller] == "iqdb"
-      if ApiLimiter.throttled?(request.remote_ip)
+      if ApiLimiter.throttled?(request.remote_ip, request.request_method)
         render :text => "421 User Throttled\n", :layout => false, :status => 421
         return false
       end

app/logical/api_limiter.rb

@@ -1,15 +1,26 @@
 module ApiLimiter
-  def throttled?(ip_addr)
-    key = "#{ip_addr}:#{Time.now.hour}"
-    MEMCACHE.fetch(key, 1.hour, :raw => true) {0}
-    MEMCACHE.incr(key).to_i > CurrentUser.user.api_hourly_limit
+  def idempotent?(method)
+    case method
+    when "POST", "PUT", "DELETE"
+      false
+
+    else
+      true
+    end
   end
 
-  def remaining_hourly_limit(ip_addr)
-    key = "#{ip_addr}:#{Time.now.hour}"
+  def throttled?(ip_addr, http_method = "GET")
+    idempotent = idempotent?(http_method)
+    key = "api/#{ip_addr}/#{Time.now.hour}/#{idempotent}"
+    MEMCACHE.fetch(key, 1.hour, :raw => true) {0}
+    MEMCACHE.incr(key).to_i > CurrentUser.user.api_hourly_limit(idempotent)
+  end
+
+  def remaining_hourly_limit(ip_addr, idempotent = true)
+    key = "api/#{ip_addr}/#{Time.now.hour}/#{idempotent}"
     requests = MEMCACHE.fetch(key, 1.hour, :raw => true) {0}.to_i
     CurrentUser.user.api_hourly_limit - requests
   end
   
-  module_function :throttled?, :remaining_hourly_limit
+  module_function :throttled?, :idempotent?, :remaining_hourly_limit
 end

app/models/user.rb

@@ -611,20 +611,34 @@ class User < ActiveRecord::Base
       end
     end
 
-    def api_hourly_limit
-      if is_platinum? && api_key.present?
-        20_000
+    def api_hourly_limit(idempotent = true)
+      base = if is_platinum? && api_key.present?
+        2000
       elsif is_gold? && api_key.present?
-        10_000
+        1000
       else
-        3_000
+        300
+      end
+
+      if idempotent
+        base * 10
+      else
+        base
       end
     end
 
     def remaining_api_hourly_limit
-      ApiLimiter.remaining_hourly_limit(CurrentUser.ip_addr)
+      ApiLimiter.remaining_hourly_limit(CurrentUser.ip_addr, true)
     end
-    
+
+    def remaining_api_hourly_limit_read
+      ApiLimiter.remaining_hourly_limit(CurrentUser.ip_addr, true)
+    end
+
+    def remaining_api_hourly_limit_write
+      ApiLimiter.remaining_hourly_limit(CurrentUser.ip_addr, false)
+    end
+
     def statement_timeout
       if is_platinum?
         9_000
@@ -644,7 +658,7 @@ class User < ActiveRecord::Base
     def method_attributes
       list = [:is_banned, :can_approve_posts, :can_upload_free, :is_super_voter, :level_string]
       if id == CurrentUser.user.id
-        list += [:remaining_api_hourly_limit]
+        list += [:remaining_api_hourly_limit, :remaining_api_hourly_limit_read, :remaining_api_hourly_limit_write]
       end
       list
     end