Connection Pool for Redis (#448)

* Connection Pool for Redis

* Removed comments

* Using Stealth::RedisSupport instead of $redis

* Added bigdecimal for ruby >= 3.4

* Removed pry gems

* Removed pry gems

* Added bigdecimal

* Added mutex_m gem

* Updated Gemfile.lock

* Updated CI

* Removed unnecessary gems

* Updated redis gem version

* Update CI truffleruby-head to truffleruby

Author: kladaFOX

.github/workflows/ci.yml

@@ -11,13 +11,11 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-20.04, ubuntu-22.04, macos-latest]
-        ruby: [ 2.7, 3.0, 3.1, 3.2, truffleruby-head ]
+        os: [ubuntu-22.04, macos-latest]
+        ruby: [ 3.3, truffleruby ]
         exclude:
           - os: ubuntu-22.04
-            ruby: 2.7
-          - os: ubuntu-22.04
-            ruby: truffleruby-head
+            ruby: truffleruby
 
     runs-on: ${{ matrix.os }}
 

.gitignore

@@ -10,3 +10,4 @@
 .yardoc
 doc/
 *.gem
+/.idea

Gemfile.lock

@@ -1,8 +1,9 @@
 PATH
   remote: .
   specs:
-    stealth (2.0.0.beta7)
+    stealth (2.1.0)
       activesupport (~> 7.0)
+      connection_pool (~> 2.4)
       multi_json (~> 1.12)
       puma (~> 6.0)
       redis (~> 5.0)
@@ -19,11 +20,13 @@ GEM
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
       tzinfo (~> 2.0)
-    concurrent-ruby (1.2.2)
-    connection_pool (2.4.1)
+    base64 (0.3.0)
+    concurrent-ruby (1.3.5)
+    connection_pool (2.5.3)
     diff-lcs (1.5.0)
     i18n (1.13.0)
       concurrent-ruby (~> 1.0)
+    logger (1.7.0)
     minitest (5.18.0)
     mock_redis (0.36.0)
       ruby2_keywords
@@ -34,14 +37,14 @@ GEM
     oj (3.14.3)
     puma (6.3.0)
       nio4r (~> 2.0)
-    rack (2.2.7)
+    rack (2.2.17)
     rack-protection (3.0.6)
       rack
     rack-test (2.1.0)
       rack (>= 1.3)
-    redis (5.0.6)
-      redis-client (>= 0.9.0)
-    redis-client (0.14.1)
+    redis (5.4.1)
+      redis-client (>= 0.22.0)
+    redis-client (0.25.1)
       connection_pool
     rspec (3.12.0)
       rspec-core (~> 3.12.0)
@@ -57,11 +60,12 @@ GEM
       rspec-support (~> 3.12.0)
     rspec-support (3.12.0)
     ruby2_keywords (0.0.5)
-    sidekiq (7.1.2)
-      concurrent-ruby (< 2)
+    sidekiq (7.3.9)
+      base64
       connection_pool (>= 2.3.0)
+      logger
       rack (>= 2.2.4)
-      redis-client (>= 0.14.0)
+      redis-client (>= 0.22.2)
     sinatra (3.0.6)
       mustermann (~> 3.0)
       rack (~> 2.2, >= 2.2.4)

VERSION

@@ -1 +1 @@
-2.0.0.beta7
+2.1.0

lib/stealth/base.rb

@@ -21,6 +21,7 @@
 require 'stealth/logger'
 require 'stealth/configuration'
 require 'stealth/reloader'
+require 'stealth/redis'
 
 # helpers
 require 'stealth/helpers/redis'

lib/stealth/controller/catch_all.rb

@@ -52,7 +52,7 @@ def run_catch_all(err:)
         private
 
           def fetch_error_level
-            if fail_attempts = $redis.get(error_slug)
+            if fail_attempts = Stealth::RedisSupport.with { |r| r.get(error_slug) }
               begin
                 fail_attempts = Integer(fail_attempts)
               rescue ArgumentError
@@ -65,7 +65,7 @@ def fetch_error_level
             end
 
             # Set the error with an expiration to avoid filling Redis
-            $redis.setex(error_slug, 15.minutes.to_i, fail_attempts)
+            Stealth::RedisSupport.with { |r| r.setex(error_slug, 15.minutes.to_i, fail_attempts) }
 
             fail_attempts
           end

lib/stealth/helpers/redis.rb

@@ -12,26 +12,28 @@ def get_key(key, expiration: Stealth.config.session_ttl)
         if expiration > 0
           getex(key, expiration)
         else
-          $redis.get(key)
+          Stealth::RedisSupport.with { |r| r.get(key) }
         end
       end
 
       def delete_key(key)
-        $redis.del(key)
+        Stealth::RedisSupport.with { |r| r.del(key) }
       end
 
       def getex(key, expiration=Stealth.config.session_ttl)
-        $redis.multi do |pipeline|
-          pipeline.expire(key, expiration)
-          pipeline.get(key)
-        end.last
+        Stealth::RedisSupport.with do |r|
+          r.multi do |pipeline|
+            pipeline.expire(key, expiration)
+            pipeline.get(key)
+          end.last
+        end
       end
 
       def persist_key(key:, value:, expiration: Stealth.config.session_ttl)
         if expiration > 0
-          $redis.setex(key, expiration, value)
+          Stealth::RedisSupport.with { |r| r.setex(key, expiration, value) }
         else
-          $redis.set(key, value)
+          Stealth::RedisSupport.with { |r| r.set(key, value) }
         end
       end
 

lib/stealth/redis.rb

@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+require "redis"
+require "connection_pool"
+
+module Stealth
+  class RedisConfig
+    attr_accessor :url, :pool_size, :pool_timeout
+
+    def initialize
+      @url          = Stealth.env.development? ? "redis://localhost:6379/0" : ENV["STEALTH_REDIS_URL"] || ENV["REDIS_URL"]
+      @pool_size    = Integer(ENV["STEALTH_REDIS_POOL"] || 5)
+      @pool_timeout = Integer(ENV["STEALTH_REDIS_TIMEOUT"] || 5)
+    end
+
+    def to_redis_kwargs
+      { url: url }
+    end
+  end
+
+  module RedisSupport
+    class << self
+      def config
+        @config ||= RedisConfig.new
+      end
+
+      def configure
+        yield(config)
+        reset_pool!
+      end
+
+      def pool
+        @pool ||= build_pool
+      end
+
+      def with(&blk)
+        pool.with(&blk)
+      end
+
+      def connection_pool
+        pool
+      end
+
+      def reset_pool!
+        if defined?(@pool) && @pool
+          @pool.shutdown(&:close) rescue nil
+        end
+        @pool = nil
+      end
+
+      private
+
+      def build_pool
+        ConnectionPool.new(size: config.pool_size, timeout: config.pool_timeout) do
+          ::Redis.new(**config.to_redis_kwargs)
+        end
+      end
+    end
+  end
+end
+

lib/stealth/session.rb

@@ -20,10 +20,10 @@ def initialize(id: nil, type: :primary)
       @type = type
 
       if id.present?
-        unless defined?($redis) && $redis.present?
+        unless defined?(Stealth::RedisSupport) && Stealth::RedisSupport.connection_pool.present?
           raise(
             Stealth::Errors::RedisNotConfigured,
-            "Please make sure REDIS_URL is configured before using sessions"
+            "Please make sure STEALTH_REDIS_URL or REDIS_URL is configured before using sessions"
           )
         end
 
@@ -91,7 +91,7 @@ def set_session(new_flow:, new_state:)
     end
 
     def clear_session
-      $redis.del(session_key)
+      Stealth::RedisSupport.with { |r| r.del(session_key) }
     end
 
     def present?

spec/session_spec.rb

@@ -20,14 +20,12 @@ class FlowMap
 describe "Stealth::Session" do
   let(:id) { '0xDEADBEEF' }
 
-  it "should raise an error if $redis is not set" do
-    $redis = nil
+  it "should raise an error if Stealth::RedisSupport connection_pool is not set" do
+    allow(Stealth::RedisSupport).to receive(:connection_pool).and_return(nil)
 
     expect {
       Stealth::Session.new(id: id)
     }.to raise_error(Stealth::Errors::RedisNotConfigured)
-
-    $redis = MockRedis.new
   end
 
   describe "without a session" do