small performance improvements

Author: netrusov

lib/grape/cache.rb

@@ -1,13 +1,18 @@
 # frozen_string_literal: true
 
+require 'active_support/cache'
+require 'active_support/concern'
 require 'grape'
+require 'rack'
 
 require 'grape/cache/configurable'
+require 'grape/cache/dsl'
+require 'grape/cache/helpers'
+require 'grape/cache/version'
+
 require 'grape/cache/extensions/dsl'
 require 'grape/cache/extensions/instance'
 require 'grape/cache/extensions/middleware/formatter'
-require 'grape/cache/helpers'
-require 'grape/cache/version'
 
 module Grape
   # @nodoc
@@ -21,16 +26,16 @@ def self.read(key)
     end
 
     # @param key [String] cache key
-    # @param response [Object] response object
+    # @param value [Object] response object
     # @param options [Object] (see ActiveSupport::Cache#write)
     # @return [Boolean] operation status
-    def self.store(key, response, **options)
-      return false unless response
+    def self.write(key, value, **options)
+      return false unless value
 
       options.delete(:expires_in) if options[:expires_in]&.<=(0)
-      config.backend.write(key, response, options)
+      config.backend.write(key, value, options)
     rescue StandardError => e
-      ActiveSupport::Notifications.instrument('grape_cache.store_error', error: e)
+      ActiveSupport::Notifications.instrument('grape_cache.write_error', error: e)
       false
     end
   end

lib/grape/cache/configurable.rb

@@ -1,8 +1,5 @@
 # frozen_string_literal: true
 
-require 'active_support/cache'
-require 'active_support/concern'
-
 module Grape
   module Cache
     # @nodoc

lib/grape/cache/dsl.rb

@@ -27,20 +27,18 @@ def no_cache?
         end
 
         def to_s
-          options = []
-
-          options << (public? ? 'public' : 'private')
-          options << (no_cache? ? 'no-cache' : ['max-age', max_age].join('='))
-          options << 'must-revalidate' if must_revalidate?
-
-          options.join(', ')
+          [
+            (public? ? 'public' : 'private'),
+            (no_cache? ? 'no-cache' : "max-age=#{max_age}"),
+            ('must-revalidate' if must_revalidate?)
+          ].compact.join(', ')
         end
       end
 
-      delegate :[], :[]=, :fetch, :slice, to: :@storage
+      delegate :[], :[]=, :fetch, :slice, to: :@store
 
       def initialize
-        @storage = {
+        @store = {
           expires_in: 0,
           race_condition_ttl: 5.seconds.to_i,
           cache_control: 'private, max-age=0, must-revalidate'
@@ -49,19 +47,19 @@ def initialize
 
       # @return [void]
       def key(value = nil, &block)
-        self[:key] = value || block
+        @store[:key] = value || block
       end
 
       # @param seconds [Integer] cache TTL
       # @return [void]
       def expires_in(seconds)
-        self[:expires_in] = seconds.to_i
+        @store[:expires_in] = seconds.to_i
       end
 
       # @param seconds [Integer] cache race condition TTL
       # @return [void]
       def race_condition_ttl(seconds)
-        self[:race_condition_ttl] = seconds.to_i
+        @store[:race_condition_ttl] = seconds.to_i
       end
 
       # @param options [Hash] parameters for "Cache-Control" header
@@ -70,8 +68,9 @@ def race_condition_ttl(seconds)
       # @option options :max_age [Integer] defaults to "expires_in"
       # @return [void]
       def cache_control(options = {})
-        self[:cache_control] =
-          CacheControl.new(options.reverse_merge(max_age: self[:expires_in])).to_s
+        @store[:cache_control] = CacheControl.new(
+          options.reverse_merge(max_age: @store[:expires_in])
+        ).to_s
       end
     end
   end

lib/grape/cache/extensions/dsl.rb

@@ -1,9 +1,5 @@
 # frozen_string_literal: true
 
-require 'active_support/concern'
-
-require 'grape/cache/dsl'
-
 module Grape
   module Cache
     module Extensions

lib/grape/cache/extensions/instance.rb

@@ -18,16 +18,17 @@ def generate_cached_api_method(context, &block) # rubocop:disable Metrics/Method
 
               key = context[:key]
               key = key.is_a?(Proc) ? instance_exec(&key) : key
-              key = Grape::Cache::Helpers.expand_cache_key(env, *key)
+              key = Grape::Cache::Helpers.expand_cache_key(env, key)
 
-              cached_response = Grape::Cache.read(key)
-              (cached_response || instance_exec(&block)).tap do |response|
-                env['grape-cache'] = {
-                  key: key,
-                  value: response,
-                  exists: !cached_response.nil?,
-                  options: context.slice(:expires_in, :race_condition_ttl).compact
-                }
+              env['grape-cache'] = { key: key }
+
+              if (value = Grape::Cache.read(key))
+                env['grape-cache'][:hit] = true
+                env['grape-cache'][:value] = value
+              else
+                env['grape-cache'][:hit] = false
+                env['grape-cache'][:options] = context.slice(:expires_in, :race_condition_ttl).compact
+                instance_exec(&block)
               end
             end
           end

lib/grape/cache/extensions/middleware/formatter.rb

@@ -10,13 +10,13 @@ def fetch_formatter(*)
             formatter = super
 
             lambda do |body, env|
-              context = env['grape-cache']
+              cache = env['grape-cache']
 
-              return formatter.call(body, env) unless context
-              return context[:value] if context[:exists]
+              return formatter.call(body, env) unless cache
+              return cache[:value] if cache[:hit]
 
               formatter.call(body, env).tap do |response|
-                Grape::Cache.store(context[:key], response, **context[:options])
+                Grape::Cache.write(cache[:key], response, **cache[:options])
               end
             end
           end

lib/grape/cache/helpers.rb

@@ -1,26 +1,22 @@
 # frozen_string_literal: true
 
-require 'active_support/cache'
-require 'rack'
-
 module Grape
   module Cache
     # @nodoc
     module Helpers
       module_function
 
       # @param env [Object] request env
-      # @param *args [String, Integer] parameters which will be concatenated into cache key
+      # @param key [#to_s, Array<#to_s>] any object or array of objects that respond to `#to_s`
       # @return [String] cache key
-      def expand_cache_key(env, *args)
-        keys = [
-          env.fetch(Rack::REQUEST_METHOD),
-          env.fetch(Rack::PATH_INFO),
-          '-',
-          *args
-        ].compact
+      def expand_cache_key(env, key)
+        key = [
+          env[Rack::REQUEST_METHOD],
+          env[Rack::PATH_INFO],
+          '-'
+        ] + Array(key).compact
 
-        ActiveSupport::Cache.expand_cache_key(keys)
+        ActiveSupport::Cache.expand_cache_key(key)
       end
     end
   end