perf: various regex caching optimizations

Author: spiderpug

lib/device_detector.rb

@@ -34,12 +34,16 @@ class DeviceDetector
   MAJOR_VERSION_4 = Gem::Version.new('4.0')
   MAJOR_VERSION_8 = Gem::Version.new('8.0')
 
+  REGEX_CACHE = ::DeviceDetector::MemoryCache.new({})
+  private_constant :REGEX_CACHE
+
   attr_reader :client_hint, :user_agent
 
   def initialize(user_agent = nil, headers = nil)
     @parsers = {}
 
     @vendor_fragment_parser = DeviceDetector::Parser::VendorFragment.new
+    @operating_system_parser = DeviceDetector::Parser::OperatingSystem.new
 
     add_parser(Parser::Client::FeedReader.new)
     add_parser(Parser::Client::MobileApp.new)
@@ -59,7 +63,7 @@ def initialize(user_agent = nil, headers = nil)
 
     add_parser(Parser::Bot.new)
 
-    use(user_agent, headers)
+    use(user_agent, headers) if user_agent || headers
   end
 
   def name
@@ -175,7 +179,7 @@ def parse_bot
   end
 
   def parse_os
-    parser = Parser::OperatingSystem.new
+    parser = @operating_system_parser
     parser.use(@user_agent, @client_hints)
 
     @os = parser.parse
@@ -340,8 +344,11 @@ def add_parser(parser)
   end
 
   def match_user_agent(regex)
-    src = regex.gsub('/', '\/')
-    regexp = Regexp.new("(?:^|[^A-Z_-])(?:#{src})", Regexp::IGNORECASE)
+    regexp = REGEX_CACHE.get_or_set(regex) do
+      src = regex.gsub('/', '\/')
+      Regexp.new("(?:^|[^A-Z_-])(?:#{src})", Regexp::IGNORECASE)
+    end
+
     match = @user_agent.match(regexp)
     return unless match
 

lib/device_detector/memory_cache.rb

@@ -2,7 +2,7 @@
 
 class DeviceDetector
   class MemoryCache
-    DEFAULT_MAX_KEYS = 5000
+    DEFAULT_MAX_KEYS = 15_000
     STORES_NIL_VALUE = :__is_nil__
 
     attr_reader :data, :max_keys, :lock

lib/device_detector/parser/abstract_parser.rb

@@ -13,6 +13,9 @@ def self.client_hint_mapping
 
       USER_AGENT_CLIENT_HINTS_FRAGMENT_REGEX = %r{Android (?:10[.\d]*; K(?: Build/|[;)])|1[1-5]\)) AppleWebKit}i
 
+      DESKTOP_FRAGMENT_REGEX = /(?:Windows (?:NT|IoT)|X11; Linux x86_64)/i
+      DESKTOP_FRAGMENT_NON_DESKTOP_REGEX = %r{CE-HTML| Mozilla/|Andr[o0]id|Tablet|Mobile|iPhone|Windows Phone|ricoh|OculusBrowser|PicoBrowser|Lenovo|compatible; MSIE|Trident/|Tesla/|XBOX|FBMD/|ARM; ?([^)]+)}i
+
       def use(uas, hints)
         @user_agent = uas
         @client_hints = hints
@@ -96,15 +99,8 @@ def user_agent_client_hints_fragment?
       end
 
       def desktop_fragment?
-        regex =
-          [
-            'CE-HTML',
-            ' Mozilla/|Andr[o0]id|Tablet|Mobile|iPhone|Windows Phone|ricoh|OculusBrowser',
-            'PicoBrowser|Lenovo|compatible; MSIE|Trident/|Tesla/|XBOX|FBMD/|ARM; ?([^)]+)'
-          ].join('|')
-
-        match_user_agent('(?:Windows (?:NT|IoT)|X11; Linux x86_64)') &&
-          !match_user_agent(regex)
+        match_user_agent_r(DESKTOP_FRAGMENT_REGEX) &&
+          !match_user_agent_r(DESKTOP_FRAGMENT_NON_DESKTOP_REGEX)
       end
 
       def fixture_file
@@ -137,21 +133,24 @@ def load_regexes
       end
 
       def pre_match_overall?
-        overall_regex = REGEX_CACHE.get_or_set("overall-#{fixture_file}") do
-          regex_list = load_regexes
-          regex_list = regex_list.values if regex_list.is_a?(Hash)
-
-          full_regex = regex_list.reduce('') do |res, regex|
-            if regex
-              "#{res}|#{regex['regex']}"
-            else
-              res
-            end
-          end.delete_prefix('|')
+        regex_from_user_agent_cache('overall') do
+          overall_regex = REGEX_CACHE.get_or_set("overall-#{fixture_file}") do
+            regex_list = load_regexes
+            regex_list = regex_list.values if regex_list.is_a?(Hash)
+
+            full_regex = regex_list.reduce('') do |res, regex|
+              if regex
+                "#{res}|#{regex['regex']}"
+              else
+                res
+              end
+            end.delete_prefix('|')
+
+            build_regex_for_ua(full_regex)
+          end
 
-          build_regex_for_ua(full_regex)
+          match_user_agent_r(overall_regex)
         end
-        match_user_agent_r(overall_regex)
       end
 
       def match_user_agent(regex)

lib/device_detector/parser/bot.rb

@@ -8,10 +8,8 @@ def parser_type
       end
 
       def parse
-        return nil unless pre_match_overall?
-
         regex_from_user_agent_cache do
-          regexes.detect do |regex|
+          pre_match_overall? && regexes.detect do |regex|
             match_user_agent_r(regex[:regex])
           end
         end

lib/device_detector/parser/client/abstract_client_parser.rb

@@ -14,22 +14,22 @@ def parser_type
         end
 
         def parse
-          return unless pre_match_overall?
+          regex_from_user_agent_cache do
+            next nil unless pre_match_overall?
 
-          regex, matches = regex_from_user_agent_cache do
-            regexes.detect do |regex|
+            regex, matches = regexes.detect do |regex|
               match = match_user_agent_r(regex[:regex])
               match ? break [regex, match] : nil
             end
-          end
 
-          return nil unless regex
+            next nil unless regex
 
-          {
-            type: parser_name,
-            name: build_by_match(regex[:name], matches),
-            version: build_version(regex[:version].to_s, matches)
-          }
+            {
+              type: parser_name,
+              name: build_by_match(regex[:name], matches),
+              version: build_version(regex[:version].to_s, matches)
+            }
+          end
         end
       end
     end

lib/device_detector/parser/client/browser.rb

@@ -6,9 +6,13 @@ class DeviceDetector
   module Parser
     module Client
       class Browser < AbstractClientParser
-        def use(uas, hints)
+        def initialize
           super
           @browser_hints = DeviceDetector::Parser::Client::Hint::BrowserHints.new
+        end
+
+        def use(uas, hints)
+          super
           @browser_hints.use(uas, hints)
         end
 

lib/device_detector/parser/client/mobile_app.rb

@@ -6,9 +6,13 @@ class DeviceDetector
   module Parser
     module Client
       class MobileApp < AbstractClientParser
-        def use(uas, hints)
+        def initialize
           super
           @app_hints = DeviceDetector::Parser::Client::Hint::AppHints.new
+        end
+
+        def use(uas, hints)
+          super
           @app_hints.use(uas, hints)
         end
 

lib/device_detector/parser/device/hbb_tv.rb

@@ -4,6 +4,11 @@ class DeviceDetector
   module Parser
     module Device
       class HbbTv < AbstractDeviceParser
+        def initialize
+          super
+          @hbb_regex = build_regex_for_ua('(?:HbbTV|SmartTvA)/([1-9]{1}(?:\.[0-9]{1}){1,2})')
+        end
+
         def parse
           return nil unless hbb_tv?
 
@@ -25,8 +30,7 @@ def parser_name
         end
 
         def hbb_tv?
-          regex = '(?:HbbTV|SmartTvA)/([1-9]{1}(?:\.[0-9]{1}){1,2})'
-          match_user_agent(regex)
+          match_user_agent_r(@hbb_regex)
         end
       end
     end

lib/device_detector/parser/device/notebook.rb

@@ -4,8 +4,13 @@ class DeviceDetector
   module Parser
     module Device
       class Notebook < AbstractDeviceParser
+        def initialize
+          super
+          @notebook_regex = build_regex_for_ua('FBMD/')
+        end
+
         def parse
-          return nil unless match_user_agent('FBMD/')
+          return nil unless match_user_agent_r(@notebook_regex)
 
           super
         end

lib/device_detector/parser/device/shell_tv.rb

@@ -4,6 +4,11 @@ class DeviceDetector
   module Parser
     module Device
       class ShellTv < AbstractDeviceParser
+        def initialize
+          super
+          @shell_tv_regex = build_regex_for_ua('[a-z]+[ _]Shell[ _]\w{6}|tclwebkit(\d+[.\d]*)')
+        end
+
         def parse
           return nil unless shell_tv?
 
@@ -25,8 +30,7 @@ def parser_name
         end
 
         def shell_tv?
-          regex = '[a-z]+[ _]Shell[ _]\w{6}|tclwebkit(\d+[.\d]*)'
-          match_user_agent(regex)
+          match_user_agent_r(@shell_tv_regex)
         end
       end
     end