Add /gc URL to status server to do a major GC. Add a /gc-status URL to get GC.stats as JSON. (#1384)

lib/puma/app/status.rb

@@ -55,6 +55,14 @@ module Puma
             return rack_response(200, OK_STATUS)
           end
 
+        when /\/gc$/
+          GC.start
+          return rack_response(200, OK_STATUS)
+
+        when /\/gc-stats$/
+          json = "{" + GC.stat.map { |k, v| "\"#{k}\": #{v}" }.join(",") + "}"
+          return rack_response(200, json)
+
         when /\/stats$/
           return rack_response(200, @cli.stats)
         else

lib/puma/control_cli.rb

@@ -9,7 +9,7 @@ require 'socket'
 module Puma
   class ControlCLI
 
-    COMMANDS = %w{halt restart phased-restart start stats status stop reload-worker-directory}
+    COMMANDS = %w{halt restart phased-restart start stats status stop reload-worker-directory gc gc-stats}
 
     def initialize(argv, stdout=STDOUT, stderr=STDERR)
       @state = nil
@@ -169,7 +169,7 @@ module Puma
         end
 
         message "Command #{@command} sent success"
-        message response.last if @command == "stats"
+        message response.last if @command == "stats" || @command == "gc-stats"
       end
 
       @server.close

test/test_cli.rb

@@ -145,6 +145,60 @@ class TestCLI < Minitest::Test
     t.join
   end
 
+  def test_control_gc_stats
+    url = "unix://#{@tmp_path}"
+
+    cli = Puma::CLI.new ["-b", "unix://#{@tmp_path2}",
+                         "--control", url,
+                         "--control-token", "",
+                         "test/rackup/lobster.ru"], @events
+
+    t = Thread.new { cli.run }
+    t.abort_on_exception = true
+
+    wait_booted
+
+    s = UNIXSocket.new @tmp_path
+    s << "GET /gc-stats HTTP/1.0\r\n\r\n"
+    body = s.read
+    s.close
+
+    lines = body.split("\r\n")
+    json_line = lines.detect { |l| l[0] == "{" }
+    pairs = json_line.scan(/\"[^\"]+\": [^,]+/)
+    gc_stats = {}
+    pairs.each do |p|
+      p =~ /\"([^\"]+)\": ([^,]+)/ || raise("Can't parse #{p.inspect}!")
+      gc_stats[$1] = $2
+    end
+    gc_count_before = gc_stats["count"].to_i
+
+    s = UNIXSocket.new @tmp_path
+    s << "GET /gc HTTP/1.0\r\n\r\n"
+    body = s.read # Ignored
+    s.close
+
+    s = UNIXSocket.new @tmp_path
+    s << "GET /gc-stats HTTP/1.0\r\n\r\n"
+    body = s.read
+    s.close
+    lines = body.split("\r\n")
+    json_line = lines.detect { |l| l[0] == "{" }
+    pairs = json_line.scan(/\"[^\"]+\": [^,]+/)
+    gc_stats = {}
+    pairs.each do |p|
+      p =~ /\"([^\"]+)\": ([^,]+)/ || raise("Can't parse #{p.inspect}!")
+      gc_stats[$1] = $2
+    end
+    gc_count_after = gc_stats["count"].to_i
+
+    # Hitting the /gc route should increment the count by 1
+    assert_equal gc_count_before + 1, gc_count_after
+
+    cli.launcher.stop
+    t.join
+  end
+
   def test_tmp_control
     url = "tcp://127.0.0.1:8232"
     cli = Puma::CLI.new ["--state", @tmp_path, "--control", "auto"]