Rudimentary retry support through xautoclaim

.github/workflows/release.yml

@@ -0,0 +1,43 @@
+name: release
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  release-please:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: GoogleCloudPlatform/release-please-action@v2
+        id: release
+        with:
+          release-type: ruby
+          package-name: nagare-redis
+          bump-minor-pre-major: true
+          version-file: "lib/nagare/version.rb"
+      # Checkout code if release was created
+      - uses: actions/checkout@v2
+        if: ${{ steps.release.outputs.release_created }}
+      # Setup ruby if a release was created
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: 2.6.5
+        if: ${{ steps.release.outputs.release_created }}
+      # Bundle install
+      - run: bundle install
+        if: ${{ steps.release.outputs.release_created }}
+      # Publish
+      - name: publish gem
+        run: |
+          mkdir -p $HOME/.gem
+          touch $HOME/.gem/credentials
+          chmod 0600 $HOME/.gem/credentials
+          printf -- "---\n:rubygems_api_key: ${GEM_HOST_API_KEY}\n" > $HOME/.gem/credentials
+          gem build *.gemspec
+          gem push *.gem
+        env:
+          # Make sure to update the secret name
+          # if yours isn't named RUBYGEMS_AUTH_TOKEN
+          GEM_HOST_API_KEY: "${{secrets.RUBYGEMS_AUTH_TOKEN}}"
+        if: ${{ steps.release.outputs.release_created }}

.github/workflows/run-tests.yml

@@ -15,9 +15,9 @@ jobs:
       - uses: actions/checkout@v2
 
       - name: Set up Ruby 2.6
-        uses: actions/setup-ruby@v1
+        uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 2.6.6
+          ruby-version: 2.6.8
 
       - uses: actions/cache@v1
         with:

Gemfile

@@ -4,4 +4,5 @@ source 'https://rubygems.org'
 gemspec
 
 gem 'rake', '~> 12.0'
+gem 'redis', github: 'vavato-be/redis-rb'
 gem 'rspec', '~> 3.0'

Gemfile.lock

@@ -1,22 +1,27 @@
+GIT
+  remote: https://github.com/vavato-be/redis-rb.git
+  revision: 79f36a58e69beb72f3bcef2ae584b30324fa2f07
+  specs:
+    redis (6.2.0)
+
 PATH
   remote: .
   specs:
-    nagare-redis (0.1.3)
-      redis (~> 4.1, >= 4.1.0)
+    nagare-redis (0.1.5)
+      redis (~> 6.2, >= 6.2.0)
 
 GEM
   remote: https://rubygems.org/
   specs:
-    ast (2.4.1)
+    ast (2.4.2)
     diff-lcs (1.3)
-    parallel (1.19.2)
-    parser (2.7.1.4)
+    parallel (1.20.1)
+    parser (3.0.2.0)
       ast (~> 2.4.1)
     rainbow (3.0.0)
     rake (12.3.2)
-    redis (4.2.1)
-    regexp_parser (1.7.1)
-    rexml (3.2.4)
+    regexp_parser (2.1.1)
+    rexml (3.2.5)
     rspec (3.9.0)
       rspec-core (~> 3.9.0)
       rspec-expectations (~> 3.9.0)
@@ -30,31 +35,33 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.9.0)
     rspec-support (3.9.3)
-    rubocop (0.88.0)
+    rubocop (1.18.3)
       parallel (~> 1.10)
-      parser (>= 2.7.1.1)
+      parser (>= 3.0.0.0)
       rainbow (>= 2.2.2, < 4.0)
-      regexp_parser (>= 1.7)
+      regexp_parser (>= 1.8, < 3.0)
       rexml
-      rubocop-ast (>= 0.1.0, < 1.0)
+      rubocop-ast (>= 1.7.0, < 2.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 1.4.0, < 2.0)
-    rubocop-ast (0.2.0)
-      parser (>= 2.7.0.1)
-    rubocop-rspec (1.42.0)
-      rubocop (>= 0.87.0)
-    ruby-progressbar (1.10.1)
-    unicode-display_width (1.7.0)
+      unicode-display_width (>= 1.4.0, < 3.0)
+    rubocop-ast (1.7.0)
+      parser (>= 3.0.1.1)
+    rubocop-rspec (2.4.0)
+      rubocop (~> 1.0)
+      rubocop-ast (>= 1.1.0)
+    ruby-progressbar (1.11.0)
+    unicode-display_width (2.0.0)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
   nagare-redis!
   rake (~> 12.0)
+  redis!
   rspec (~> 3.0)
-  rubocop (~> 0.88, >= 0.88)
-  rubocop-rspec (~> 1.42, >= 1.42.0)
+  rubocop (~> 1.18.3, >= 1.18.3)
+  rubocop-rspec (~> 2.4.0, >= 2.4.0)
 
 BUNDLED WITH
    2.1.0

README.md

@@ -40,20 +40,25 @@ To use with rails, add nagare to the initializers:
 #### config/initializers/nagare.rb
 ```ruby
 Nagare.configure do |config|
-  # After x seconds a consumer is considered dead and its messages
-  # are assigned to a different consumer in the group. Configuring
+  # After x milisseconds a pending message is considered failed and
+  # gets retried by a different consumer in the group. Configuring
   # it too low might cause double processing of messages as a consumer
   # "steals" the load of another while the first one is still processing
   # it and hasn't had the chance to ACK, configuring it too high will 
   # introduce latency in your processing.
-  # Default: 300 (5 minutes)
-  config.dead_consumer_timeout = 600
+  # Default: 600.000 (10 minutes)
+  config.min_idle_time = 600_0000
 
   # This is the consumer group name that will be used or created in
   # Redis. Use a different group for every microservice / application
   # Default: Rails.env
   config.group_name = :monolith
 
+  # A suffix is supported in order to separate different environments
+  # within the same redis database. Useful for development/test. This
+  # gets added automatically to stream names and consumer group names.
+  config.suffix = ''
+
   # URL to connect to redis. Defaults to redis://localhost:6379 uses 
   # ENV['REDIS_URL'] if present.
   config.redis_url = 'redis://10.1.1.1:6379'

lib/nagare/config.rb

@@ -5,22 +5,24 @@ module Nagare
   # See the README for possible values and what they do
   class Config
     class << self
-      attr_accessor :dead_consumer_timeout, :group_name, :redis_url, :threads,
-                    :suffix
+      attr_accessor :group_name, :redis_url, :threads, :suffix, :min_idle_time
 
       # Runs code in the block passed in to configure Nagare and sets defaults
       # when values are not set.
       #
-      # returns Nagare::Config self
+      # returns [Nagare::Config] self
+      # rubocop:disable Metrics/CyclomaticComplexity
       def configure
         yield(self)
         @dead_consumer_timeout ||= 5000
         @group_name ||= 'nagare'
         @redis_url = redis_url || ENV['REDIS_URL'] || 'redis://localhost:6379'
         @threads ||= 1
         @suffix ||= nil
+        @min_idle_time ||= 600_000
         self
       end
+      # rubocop:enable Metrics/CyclomaticComplexity
     end
   end
 end

lib/nagare/listener.rb

@@ -43,6 +43,7 @@ def stream_name
     # The ClassMethods module is automatically loaded into child classes
     # effectively adding the `stream` class method to the child class.`
     def self.inherited(subclass)
+      super
       subclass.extend(ClassMethods)
     end
 

lib/nagare/listener_pool.rb

@@ -59,22 +59,30 @@ def poll
       private
 
       def poll_stream(stream, listeners)
-        # TODO: Use thread pool
-        messages = Nagare::RedisStreams.read_next_messages(stream, group)
+        return unless Nagare::RedisStreams.group_exists?(stream, group)
+
+        messages = Nagare::RedisStreams.claim_next_stuck_message(stream, group)
+
+        if messages.nil? || messages.empty?
+          messages = Nagare::RedisStreams.read_next_messages(stream, group)
+        end
         return unless messages.any?
 
         messages.each do |message|
           deliver_message(stream, message, listeners)
         end
       end
 
+      def claim_pending_messages(stream)
+        return nil unless Nagare::RedisStreams.group_exists?(stream, group)
+      end
+
       def deliver_message(stream, message, listeners)
         listener_failed = false
 
         listeners.each do |listener|
           invoke_listener(stream, message, listener)
         rescue StandardError => e
-          # TODO: Retry logic
           logger.error e.message
           logger.error e.backtrace.join("\n")
           listener_failed = true

lib/nagare/redis_streams.rb

@@ -30,7 +30,6 @@ def connection
       # @param group [String] name of the group
       #
       # @return [Boolean] true if the group exists, otherwise false
-      # rubocop:disable Metrics/AbcSize
       def group_exists?(stream, group)
         stream = stream_name(stream)
         info = connection.xinfo(:groups, stream.to_s)
@@ -41,7 +40,6 @@ def group_exists?(stream, group)
         logger.info e.backtrace.join("\n")
         false
       end
-      # rubocop:enable Metrics/AbcSize
 
       ##
       # Creates a group in redis for the stream using xgroup
@@ -81,6 +79,25 @@ def publish(stream, event_name, data)
         connection.xadd(stream, { "#{event_name}": data })
       end
 
+      ##
+      # Claums the next message of the consumer group that is stuck
+      # (pending and past min_idle_time since being picked up)
+      #
+      # @param stream [String] name of the stream
+      # @param group [String] name of the consumer group
+      #
+      # @return [Array[Hash]] array containing the 1 message or empty
+      def claim_next_stuck_message(stream, group)
+        stream = stream_name(stream)
+        result = connection.xautoclaim(stream,
+                                       "#{stream}-#{group}",
+                                       "#{hostname}-#{thread_id}",
+                                       Nagare::Config.min_idle_time,
+                                       '0-0',
+                                       count: 1)
+        result['entries'] || []
+      end
+
       ##
       # Reads the next messages from the consumer group in redis.
       #

lib/nagare/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Nagare
-  VERSION = '0.1.4'
+  VERSION = '0.1.5'
 end

nagare.gemspec

@@ -20,14 +20,16 @@ Gem::Specification.new do |spec|
   spec.metadata['source_code_uri'] = 'https://github.com/vavato-be/nagare.git'
   spec.metadata['changelog_uri'] = 'https://github.com/vavato-be/nagare/CHANGELOG.md'
 
-  spec.add_dependency 'redis', '~> 4.1', '>= 4.1.0'
-  spec.add_development_dependency 'rubocop', '~> 0.88', '>= 0.88'
-  spec.add_development_dependency 'rubocop-rspec', '~> 1.42', '>= 1.42.0'
+  spec.add_dependency 'redis', '~> 6.2', '>= 6.2.0'
+  spec.add_development_dependency 'rubocop', '~> 1.18.3', '>= 1.18.3'
+  spec.add_development_dependency 'rubocop-rspec', '~> 2.4.0', '>= 2.4.0'
 
   # Specify which files should be added to the gem when it is released.
   # The `git ls-files -z` loads the files in the RubyGem that have been added into git.
   spec.files = Dir.chdir(File.expand_path(__dir__)) do
-    `git ls-files -z`.split("\x0").reject { |f| f.match(%r{^(test|spec|features)/}) }
+    `git ls-files -z`.split("\x0").reject do |f|
+      f.match(%r{^(test|spec|features)/})
+    end
   end
   spec.bindir = 'exe'
   spec.executables << 'nagare'

spec/lib/nagare/listener_pool_spec.rb

@@ -10,6 +10,8 @@
 
   before do
     allow(Nagare::Config).to receive(:group_name).and_return(group)
+    allow(Nagare::RedisStreams).to receive(:claim_next_stuck_message).and_return([])
+    allow(Nagare::RedisStreams).to receive(:group_exists?).and_return(true)
   end
 
   describe '.start_listening' do
@@ -53,7 +55,8 @@
 
       context 'when the listener processes the event without raising errors' do
         before do
-          allow(Nagare::RedisStreams).to receive(:read_next_messages).and_return([[message_id, event]])
+          allow(Nagare::RedisStreams).to receive(:read_next_messages)
+            .and_return([[message_id, event]])
           allow(Nagare::RedisStreams).to receive(:mark_processed)
           described_class.poll
         end
@@ -63,14 +66,17 @@
         end
 
         it 'marks the message as processed (ACK) with the redis streams group' do
-          expect(Nagare::RedisStreams).to have_received(:mark_processed).with(stream.to_sym, group, message_id)
+          expect(Nagare::RedisStreams).to have_received(:mark_processed).with(
+            stream.to_sym, group, message_id
+          )
         end
       end
 
       context 'when the listener raises an error' do
         before do
           allow(described_class).to receive(:listener_pool).and_return({ 'listener_pool_spec': [listener_class] })
-          allow(Nagare::RedisStreams).to receive(:read_next_messages).and_return([[message_id, event]])
+          allow(Nagare::RedisStreams).to receive(:read_next_messages)
+            .and_return([[message_id, event]])
           allow(Nagare::RedisStreams).to receive(:mark_processed)
           allow(listener).to receive(:handle_event).and_raise('Processing error')
 
@@ -82,7 +88,42 @@
         end
 
         it 'does NOT mark the message as processed (ACK) with the redis streams group' do
-          expect(Nagare::RedisStreams).not_to have_received(:mark_processed).with(stream.to_sym, group, message_id)
+          expect(Nagare::RedisStreams).not_to have_received(:mark_processed).with(
+            stream.to_sym, group, message_id
+          )
+        end
+      end
+    end
+
+    context 'when there are listeners registered and a pending event in the stream' do
+      let(:event) { { foo: 'bar' } }
+      let(:message_id) { 'message_id-0' }
+
+      before do
+        allow(described_class).to receive(:listener_pool).and_return({ 'listener_pool_spec': [listener_class] })
+      end
+
+      context 'when the listener processes the event without raising errors' do
+        before do
+          allow(Nagare::RedisStreams).to receive(:claim_next_stuck_message)
+            .and_return([[message_id, event]])
+          allow(Nagare::RedisStreams).to receive(:read_next_messages)
+          allow(Nagare::RedisStreams).to receive(:mark_processed)
+          described_class.poll
+        end
+
+        it 'invokes #handle_event on the listener, passing in the event' do
+          expect(listener).to have_received(:handle_event).with(event)
+        end
+
+        it 'marks the message as processed (ACK) with the redis streams group' do
+          expect(Nagare::RedisStreams).to have_received(:mark_processed).with(
+            stream.to_sym, group, message_id
+          )
+        end
+
+        it 'does not try to read the next message from the stream' do
+          expect(Nagare::RedisStreams).not_to have_received(:read_next_messages)
         end
       end
     end