DEV: Remove `StatsSocket`.

Removed in favor of https://github.com/discourse/discourse-prometheus.

config/unicorn.conf.rb

@@ -47,28 +47,6 @@ preload_app true
 # fast LAN.
 check_client_connection false
 
-@stats_socket_dir = ENV["UNICORN_STATS_SOCKET_DIR"]
-
-def clean_up_stats_socket(server, pid)
-  if @stats_socket_dir.present?
-    name = "#{@stats_socket_dir}/#{pid}.sock"
-    FileUtils.rm_f(name)
-    server.logger.info "Cleaned up stats socket at #{name}"
-  end
-rescue => e
-  server.logger.warn "Failed to clean up stats socket #{e}"
-end
-
-def start_stats_socket(server)
-  if @stats_socket_dir.present?
-    name = "#{@stats_socket_dir}/#{Process.pid}.sock"
-    StatsSocket.new(name).start
-    server.logger.info "Started stats socket at #{name}"
-  end
-rescue => e
-  server.logger.warn "Failed to start stats socket #{e}"
-end
-
 initialized = false
 before_fork do |server, worker|
 
@@ -84,18 +62,6 @@ before_fork do |server, worker|
     # router warm up
     Rails.application.routes.recognize_path('abc') rescue nil
 
-    if @stats_socket_dir.present?
-      server.logger.info "Initializing stats socket at #{@stats_socket_dir}"
-      begin
-        require 'stats_socket'
-        FileUtils.mkdir_p @stats_socket_dir
-        FileUtils.rm_f Dir.glob("#{@stats_socket_dir}/*.sock")
-        start_stats_socket(server)
-      rescue => e
-        server.logger.info "Failed to initialize stats socket dir #{e}"
-      end
-    end
-
     # preload discourse version
     Discourse.git_version
     Discourse.git_branch
@@ -125,7 +91,6 @@ before_fork do |server, worker|
 
       require 'demon/sidekiq'
       Demon::Sidekiq.after_fork do
-        start_stats_socket(server) if @stats_socket_dir
         DiscourseEvent.trigger(:sidekiq_fork_started)
       end
 
@@ -220,13 +185,7 @@ before_fork do |server, worker|
   sleep 1
 end
 
-after_worker_exit do |server, worker, status|
-  clean_up_stats_socket(server, status.pid)
-end
-
 after_fork do |server, worker|
-  start_stats_socket(server)
-
   DiscourseEvent.trigger(:web_fork_started)
 
   # warm up v8 after fork, that way we do not fork a v8 context

lib/stats_socket.rb

@@ -1,31 +0,0 @@
-require 'socket_server'
-
-class StatsSocket < SocketServer
-
-  def initialize(socket_path)
-    super(socket_path)
-  end
-
-  protected
-
-  def get_response(command)
-    result =
-      case command
-      when "gc_stat"
-        GC.stat.to_json
-      when "v8_stat"
-        stats = {}
-        ObjectSpace.each_object(MiniRacer::Context) do |context|
-          context.heap_stats.each do |k, v|
-            stats[k] = (stats[k] || 0) + v
-          end
-        end
-        stats.to_json
-      else
-        "[\"UNKNOWN COMMAND\"]"
-      end
-
-    result << "\n"
-  end
-
-end

spec/components/stats_socket_spec.rb

@@ -1,57 +0,0 @@
-require 'rails_helper'
-require_dependency 'stats_socket'
-
-describe StatsSocket do
-  let :socket_path do
-    "#{Dir.tmpdir}/#{SecureRandom.hex}"
-  end
-
-  let :stats_socket do
-    StatsSocket.new(socket_path)
-  end
-
-  before do
-    stats_socket.start
-  end
-
-  after do
-    stats_socket.stop
-  end
-
-  it "can respond to various stats commands" do
-    line = nil
-
-    # ensure this works more than once :)
-    2.times do
-      socket = UNIXSocket.new(socket_path)
-      socket.send "gc_stat\n", 0
-      line = socket.readline
-      socket.close
-    end
-
-    socket = UNIXSocket.new(socket_path)
-    socket.send "gc_st", 0
-    socket.flush
-    sleep 0.001
-    socket.send "at\n", 0
-    line = socket.readline
-    socket.close
-
-    parsed = JSON.parse(line)
-
-    expect(parsed.keys.sort).to eq(GC.stat.keys.map(&:to_s).sort)
-
-    # make sure we have libv8 going
-    PrettyText.cook("x")
-
-    socket = UNIXSocket.new(socket_path)
-    socket.send "v8_stat\n", 0
-    line = socket.readline
-    socket.close
-
-    parsed = JSON.parse(line)
-
-    expect(parsed['total_physical_size']).to be > (0)
-  end
-
-end