DEV: Introduce syntax_tree for formatting (#329)

.github/workflows/ci.yml

@@ -27,7 +27,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ['3.1', '3.2', '3.3']
+        ruby: ["3.1", "3.2", "3.3"]
         activerecord: [61, 70, 71]
 
     steps:
@@ -42,6 +42,9 @@ jobs:
       - name: Rubocop
         run: bundle exec rubocop
 
+      - name: Syntax tree
+        run: bundle exec stree check Gemfile $(git ls-files '*.rb') $(git ls-files '*.rake') $(git ls-files '*.thor')
+
       - name: Run tests
         run: bundle exec rake
 

.streerc

@@ -0,0 +1,2 @@
+--print-width=100
+--plugins=plugin/trailing_comma,disable_ternary

bench/bench.rb

@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
-require_relative '../lib/prometheus_exporter'
-require_relative '../lib/prometheus_exporter/client'
-require_relative '../lib/prometheus_exporter/server'
+require_relative "../lib/prometheus_exporter"
+require_relative "../lib/prometheus_exporter/client"
+require_relative "../lib/prometheus_exporter/server"
 
 # test how long it takes a custom collector to process 10k messages
 
@@ -26,18 +26,19 @@ def prometheus_metrics_text
 @client = nil
 @runs = 1000
 
-done = lambda do
-  puts "Elapsed for 10k messages is #{Time.now - @start}"
-  if (@runs -= 1) > 0
-    @start = Time.now
-    10_000.times { @client.send_json(hello: "world") }
+done =
+  lambda do
+    puts "Elapsed for 10k messages is #{Time.now - @start}"
+    if (@runs -= 1) > 0
+      @start = Time.now
+      10_000.times { @client.send_json(hello: "world") }
+    end
   end
-end
 
 collector = Collector.new(done)
-server = PrometheusExporter::Server::WebServer.new port: 12349, collector: collector
+server = PrometheusExporter::Server::WebServer.new port: 12_349, collector: collector
 server.start
-@client = PrometheusExporter::Client.new port: 12349, max_queue_size: 100_000
+@client = PrometheusExporter::Client.new port: 12_349, max_queue_size: 100_000
 
 @start = Time.now
 10_000.times { @client.send_json(hello: "world") }

examples/custom_collector.rb

@@ -20,8 +20,6 @@ def process(obj)
   end
 
   def prometheus_metrics_text
-    @mutex.synchronize do
-      "#{@gauge1.to_prometheus_text}\n#{@gauge2.to_prometheus_text}"
-    end
+    @mutex.synchronize { "#{@gauge1.to_prometheus_text}\n#{@gauge2.to_prometheus_text}" }
   end
 end

lib/prometheus_exporter/client.rb

@@ -17,13 +17,7 @@ def initialize(name:, help:, type:, client:, opts: nil)
       end
 
       def standard_values(value, keys, prometheus_exporter_action = nil)
-        values = {
-          type: @type,
-          help: @help,
-          name: @name,
-          keys: keys,
-          value: value
-        }
+        values = { type: @type, help: @help, name: @name, keys: keys, value: value }
         values[
           :prometheus_exporter_action
         ] = prometheus_exporter_action if prometheus_exporter_action
@@ -59,10 +53,7 @@ def self.default=(client)
 
     def initialize(
       host: ENV.fetch("PROMETHEUS_EXPORTER_HOST", "localhost"),
-      port: ENV.fetch(
-        "PROMETHEUS_EXPORTER_PORT",
-        PrometheusExporter::DEFAULT_PORT
-      ),
+      port: ENV.fetch("PROMETHEUS_EXPORTER_PORT", PrometheusExporter::DEFAULT_PORT),
       max_queue_size: nil,
       thread_sleep: 0.5,
       json_serializer: nil,
@@ -83,9 +74,7 @@ def initialize(
       max_queue_size ||= MAX_QUEUE_SIZE
       max_queue_size = max_queue_size.to_i
 
-      if max_queue_size <= 0
-        raise ArgumentError, "max_queue_size must be larger than 0"
-      end
+      raise ArgumentError, "max_queue_size must be larger than 0" if max_queue_size <= 0
 
       @max_queue_size = max_queue_size
       @host = host
@@ -94,8 +83,7 @@ def initialize(
       @mutex = Mutex.new
       @thread_sleep = thread_sleep
 
-      @json_serializer =
-        json_serializer == :oj ? PrometheusExporter::OjCompat : JSON
+      @json_serializer = json_serializer == :oj ? PrometheusExporter::OjCompat : JSON
 
       @custom_labels = custom_labels
     end
@@ -105,14 +93,7 @@ def custom_labels=(custom_labels)
     end
 
     def register(type, name, help, opts = nil)
-      metric =
-        RemoteMetric.new(
-          type: type,
-          name: name,
-          help: help,
-          client: self,
-          opts: opts
-        )
+      metric = RemoteMetric.new(type: type, name: name, help: help, client: self, opts: opts)
       @metrics << metric
       metric
     end
@@ -262,10 +243,7 @@ def ensure_socket!
     def wait_for_empty_queue_with_timeout(timeout_seconds)
       start_time = ::Process.clock_gettime(::Process::CLOCK_MONOTONIC)
       while @queue.length > 0
-        if start_time + timeout_seconds <
-             ::Process.clock_gettime(::Process::CLOCK_MONOTONIC)
-          break
-        end
+        break if start_time + timeout_seconds < ::Process.clock_gettime(::Process::CLOCK_MONOTONIC)
         sleep(0.05)
       end
     end

lib/prometheus_exporter/instrumentation/active_record.rb

@@ -3,14 +3,16 @@
 # collects stats from currently running process
 module PrometheusExporter::Instrumentation
   class ActiveRecord < PeriodicStats
-    ALLOWED_CONFIG_LABELS = %i(database username host port)
+    ALLOWED_CONFIG_LABELS = %i[database username host port]
 
     def self.start(client: nil, frequency: 30, custom_labels: {}, config_labels: [])
       client ||= PrometheusExporter::Client.default
 
       # Not all rails versions support connection pool stats
       unless ::ActiveRecord::Base.connection_pool.respond_to?(:stat)
-        client.logger.error("ActiveRecord connection pool stats not supported in your rails version")
+        client.logger.error(
+          "ActiveRecord connection pool stats not supported in your rails version",
+        )
         return
       end
 
@@ -29,7 +31,9 @@ def self.start(client: nil, frequency: 30, custom_labels: {}, config_labels: [])
 
     def self.validate_config_labels(config_labels)
       return if config_labels.size == 0
-      raise "Invalid Config Labels, available options #{ALLOWED_CONFIG_LABELS}" if (config_labels - ALLOWED_CONFIG_LABELS).size > 0
+      if (config_labels - ALLOWED_CONFIG_LABELS).size > 0
+        raise "Invalid Config Labels, available options #{ALLOWED_CONFIG_LABELS}"
+      end
     end
 
     def initialize(metric_labels, config_labels)
@@ -55,7 +59,7 @@ def collect_active_record_pool_stats(metrics)
           pid: pid,
           type: "active_record",
           hostname: ::PrometheusExporter.hostname,
-          metric_labels: labels(pool)
+          metric_labels: labels(pool),
         }
         metric.merge!(pool.stat)
         metrics << metric
@@ -66,12 +70,20 @@ def collect_active_record_pool_stats(metrics)
 
     def labels(pool)
       if ::ActiveRecord.version < Gem::Version.new("6.1.0.rc1")
-        @metric_labels.merge(pool_name: pool.spec.name).merge(pool.spec.config
-          .select { |k, v| @config_labels.include? k }
-          .map { |k, v| [k.to_s.dup.prepend("dbconfig_"), v] }.to_h)
+        @metric_labels.merge(pool_name: pool.spec.name).merge(
+          pool
+            .spec
+            .config
+            .select { |k, v| @config_labels.include? k }
+            .map { |k, v| [k.to_s.dup.prepend("dbconfig_"), v] }
+            .to_h,
+        )
       else
         @metric_labels.merge(pool_name: pool.db_config.name).merge(
-          @config_labels.each_with_object({}) { |l, acc| acc["dbconfig_#{l}"] = pool.db_config.public_send(l) })
+          @config_labels.each_with_object({}) do |l, acc|
+            acc["dbconfig_#{l}"] = pool.db_config.public_send(l)
+          end,
+        )
       end
     end
   end

lib/prometheus_exporter/instrumentation/delayed_job.rb

@@ -2,24 +2,33 @@
 
 module PrometheusExporter::Instrumentation
   class DelayedJob
-    JOB_CLASS_REGEXP = %r{job_class: ((\w+:{0,2})+)}.freeze
+    JOB_CLASS_REGEXP = /job_class: ((\w+:{0,2})+)/.freeze
 
     class << self
       def register_plugin(client: nil, include_module_name: false)
         instrumenter = self.new(client: client)
         return unless defined?(Delayed::Plugin)
 
-        plugin = Class.new(Delayed::Plugin) do
-          callbacks do |lifecycle|
-            lifecycle.around(:invoke_job) do |job, *args, &block|
-              max_attempts = Delayed::Worker.max_attempts
-              enqueued_count = Delayed::Job.where(queue: job.queue).count
-              pending_count = Delayed::Job.where(attempts: 0, locked_at: nil, queue: job.queue).count
-              instrumenter.call(job, max_attempts, enqueued_count, pending_count, include_module_name,
-                                *args, &block)
+        plugin =
+          Class.new(Delayed::Plugin) do
+            callbacks do |lifecycle|
+              lifecycle.around(:invoke_job) do |job, *args, &block|
+                max_attempts = Delayed::Worker.max_attempts
+                enqueued_count = Delayed::Job.where(queue: job.queue).count
+                pending_count =
+                  Delayed::Job.where(attempts: 0, locked_at: nil, queue: job.queue).count
+                instrumenter.call(
+                  job,
+                  max_attempts,
+                  enqueued_count,
+                  pending_count,
+                  include_module_name,
+                  *args,
+                  &block
+                )
+              end
             end
           end
-        end
 
         Delayed::Worker.plugins << plugin
       end
@@ -50,7 +59,7 @@ def call(job, max_attempts, enqueued_count, pending_count, include_module_name,
         attempts: attempts,
         max_attempts: max_attempts,
         enqueued: enqueued_count,
-        pending: pending_count
+        pending: pending_count,
       )
     end
   end

lib/prometheus_exporter/instrumentation/good_job.rb

@@ -7,9 +7,7 @@ def self.start(client: nil, frequency: 30)
       good_job_collector = new
       client ||= PrometheusExporter::Client.default
 
-      worker_loop do
-        client.send_json(good_job_collector.collect)
-      end
+      worker_loop { client.send_json(good_job_collector.collect) }
 
       super
     end
@@ -23,7 +21,7 @@ def collect
         running: ::GoodJob::Job.running.size,
         finished: ::GoodJob::Job.finished.size,
         succeeded: ::GoodJob::Job.succeeded.size,
-        discarded: ::GoodJob::Job.discarded.size
+        discarded: ::GoodJob::Job.discarded.size,
       }
     end
   end

lib/prometheus_exporter/instrumentation/hutch.rb

@@ -19,7 +19,7 @@ def handle(message)
         type: "hutch",
         name: @klass.class.to_s,
         success: success,
-        duration: duration
+        duration: duration,
       )
     end
   end

lib/prometheus_exporter/instrumentation/method_profiler.rb

@@ -1,7 +1,8 @@
 # frozen_string_literal: true
 
 # see https://samsaffron.com/archive/2017/10/18/fastest-way-to-profile-a-method-in-ruby
-module PrometheusExporter::Instrumentation; end
+module PrometheusExporter::Instrumentation
+end
 
 class PrometheusExporter::Instrumentation::MethodProfiler
   def self.patch(klass, methods, name, instrument:)
@@ -21,9 +22,8 @@ def self.transfer
   end
 
   def self.start(transfer = nil)
-    Thread.current[:_method_profiler] = transfer || {
-      __start: Process.clock_gettime(Process::CLOCK_MONOTONIC)
-    }
+    Thread.current[:_method_profiler] = transfer ||
+      { __start: Process.clock_gettime(Process::CLOCK_MONOTONIC) }
   end
 
   def self.clear
@@ -42,8 +42,8 @@ def self.stop
 
   def self.define_methods_on_module(klass, methods, name)
     patch_source_line = __LINE__ + 3
-    patches = methods.map do |method_name|
-      <<~RUBY
+
+    patches = methods.map { |method_name| <<~RUBY }.join("\n")
         def #{method_name}(...)
           unless prof = Thread.current[:_method_profiler]
             return super
@@ -58,9 +58,8 @@ def #{method_name}(...)
           end
         end
       RUBY
-    end.join("\n")
 
-    klass.module_eval patches, __FILE__, patch_source_line
+    klass.module_eval(patches, __FILE__, patch_source_line)
   end
 
   def self.patch_using_prepend(klass, methods, name)
@@ -71,14 +70,16 @@ def self.patch_using_prepend(klass, methods, name)
 
   def self.patch_using_alias_method(klass, methods, name)
     patch_source_line = __LINE__ + 3
-    patches = methods.map do |method_name|
-      <<~RUBY
+
+    patches = methods.map { |method_name| <<~RUBY }.join("\n")
       unless defined?(#{method_name}__mp_unpatched)
         alias_method :#{method_name}__mp_unpatched, :#{method_name}
+
         def #{method_name}(...)
           unless prof = Thread.current[:_method_profiler]
             return #{method_name}__mp_unpatched(...)
           end
+
           begin
             start = Process.clock_gettime(Process::CLOCK_MONOTONIC)
             #{method_name}__mp_unpatched(...)
@@ -90,8 +91,7 @@ def #{method_name}(...)
         end
       end
       RUBY
-    end.join("\n")
 
-    klass.class_eval patches, __FILE__, patch_source_line
+    klass.class_eval(patches, __FILE__, patch_source_line)
   end
 end