Class RailsFCGIHandler
In: vendor/rails/railties/lib/fcgi_handler.rb
Parent: Object

Methods

Constants

SIGNALS = { 'HUP' => :reload, 'INT' => :exit_now, 'TERM' => :exit_now, 'USR1' => :exit, 'USR2' => :restart
GLOBAL_SIGNALS = SIGNALS.keys - %w(USR1)

Attributes

gc_request_period  [RW] 
log_file_path  [RW] 
when_ready  [R] 

Public Class methods

Initialize the FastCGI instance with the path to a crash log detailing unhandled exceptions (default RAILS_ROOT/log/fastcgi.crash.log) and the number of requests to process between garbage collection runs (default nil for normal GC behavior.) Optionally, pass a block which takes this instance as an argument for further configuration.

[Source]

    # File vendor/rails/railties/lib/fcgi_handler.rb, line 31
31:   def initialize(log_file_path = nil, gc_request_period = nil)
32:     self.log_file_path = log_file_path || "#{RAILS_ROOT}/log/fastcgi.crash.log"
33:     self.gc_request_period = gc_request_period
34: 
35:     # Yield for additional configuration.
36:     yield self if block_given?
37: 
38:     # Safely install signal handlers.
39:     install_signal_handlers
40: 
41:     # Start error timestamp at 11 seconds ago.
42:     @last_error_on = Time.now - 11
43:   end

Initialize and run the FastCGI instance, passing arguments through to new.

[Source]

    # File vendor/rails/railties/lib/fcgi_handler.rb, line 22
22:   def self.process!(*args, &block)
23:     new(*args, &block).process!
24:   end

Public Instance methods

[Source]

    # File vendor/rails/railties/lib/fcgi_handler.rb, line 45
45:   def process!(provider = FCGI)
46:     mark_features!
47: 
48:     dispatcher_log :info, 'starting'
49:     process_each_request provider
50:     dispatcher_log :info, 'stopping gracefully'
51: 
52:   rescue Exception => error
53:     case error
54:     when SystemExit
55:       dispatcher_log :info, 'stopping after explicit exit'
56:     when SignalException
57:       dispatcher_error error, 'stopping after unhandled signal'
58:     else
59:       # Retry if exceptions occur more than 10 seconds apart.
60:       if Time.now - @last_error_on > 10
61:         @last_error_on = Time.now
62:         dispatcher_error error, 'retrying after unhandled exception'
63:         retry
64:       else
65:         dispatcher_error error, 'stopping after unhandled exception within 10 seconds of the last'
66:       end
67:     end
68:   end

Protected Instance methods

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 234
234:     def close_connection(cgi)
235:       cgi.instance_variable_get("@request").finish if cgi
236:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 124
124:     def dispatcher_error(e, msg = "")
125:       error_message =
126:         "Dispatcher failed to catch: #{e} (#{e.class})\n" +
127:         "  #{e.backtrace.join("\n  ")}\n#{msg}"
128:       dispatcher_log(:error, error_message)
129:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 116
116:     def dispatcher_log(level, msg)
117:       time_str = Time.now.strftime("%d/%b/%Y:%H:%M:%S")
118:       logger.send(level, "[#{time_str} :: #{$$}] #{msg}")
119:     rescue Exception => log_error  # Logger errors
120:       STDERR << "Couldn't write to #{@log_file_path.inspect}: #{msg}\n"
121:       STDERR << "  #{log_error.class}: #{log_error.message}\n"
122:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 161
161:     def exit_handler(signal)
162:       dispatcher_log :info, "asked to stop ASAP"
163:       if @processing
164:         @when_ready = :exit
165:       else
166:         throw :exit
167:       end
168:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 156
156:     def exit_now_handler(signal)
157:       dispatcher_log :info, "asked to stop immediately"
158:       exit
159:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 226
226:     def gc_countdown
227:       if gc_request_period
228:         @gc_request_countdown ||= gc_request_period
229:         @gc_request_countdown -= 1
230:         run_gc! if @gc_request_countdown <= 0
231:       end
232:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 135
135:     def install_signal_handler(signal, handler = nil)
136:       if SIGNALS.include?(signal) && self.class.method_defined?(name = "#{SIGNALS[signal]}_handler")
137:         handler ||= method(name).to_proc
138: 
139:         begin
140:           trap(signal, handler)
141:         rescue ArgumentError
142:           dispatcher_log :warn, "Ignoring unsupported signal #{signal}."
143:         end
144:       else
145:         dispatcher_log :warn, "Ignoring unsupported signal #{signal}."
146:       end
147:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 131
131:     def install_signal_handlers
132:       GLOBAL_SIGNALS.each { |signal| install_signal_handler(signal) }
133:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 112
112:     def logger
113:       @logger ||= Logger.new(@log_file_path)
114:     end

Make a note of $" so we can safely reload this instance.

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 211
211:     def mark_features!
212:       @features = $".clone
213:     end

[Source]

    # File vendor/rails/railties/lib/fcgi_handler.rb, line 71
71:     def process_each_request(provider)
72:       cgi = nil
73: 
74:       catch :exit do
75:         provider.each_cgi do |cgi|
76:           process_request(cgi)
77: 
78:           case when_ready
79:             when :reload
80:               reload!
81:             when :restart
82:               close_connection(cgi)
83:               restart!
84:             when :exit
85:               close_connection(cgi)
86:               throw :exit
87:           end
88:         end
89:       end
90:     rescue SignalException => signal
91:       raise unless signal.message == 'SIGUSR1'
92:       close_connection(cgi)
93:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 95
 95:     def process_request(cgi)
 96:       @processing, @when_ready = true, nil
 97:       gc_countdown
 98: 
 99:       with_signal_handler 'USR1' do
100:         begin
101:           Dispatcher.dispatch(cgi)
102:         rescue SignalException, SystemExit
103:           raise
104:         rescue Exception => error
105:           dispatcher_error error, 'unhandled dispatch error'
106:         end
107:       end
108:     ensure
109:       @processing = false
110:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 203
203:     def reload!
204:       run_gc! if gc_request_period
205:       restore!
206:       @when_ready = nil
207:       dispatcher_log :info, "reloaded"
208:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 170
170:     def reload_handler(signal)
171:       dispatcher_log :info, "asked to reload ASAP"
172:       if @processing
173:         @when_ready = :reload
174:       else
175:         reload!
176:       end
177:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 188
188:     def restart!
189:       config       = ::Config::CONFIG
190:       ruby         = File::join(config['bindir'], config['ruby_install_name']) + config['EXEEXT']
191:       command_line = [ruby, $0, ARGV].flatten.join(' ')
192: 
193:       dispatcher_log :info, "restarted"
194: 
195:       # close resources as they won't be closed by
196:       # the OS when using exec
197:       logger.close rescue nil
198:       Rails.logger.close rescue nil
199: 
200:       exec(command_line)
201:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 179
179:     def restart_handler(signal)
180:       dispatcher_log :info, "asked to restart ASAP"
181:       if @processing
182:         @when_ready = :restart
183:       else
184:         restart!
185:       end
186:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 215
215:     def restore!
216:       $".replace @features
217:       Dispatcher.reset_application!
218:       ActionController::Routing::Routes.reload
219:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 221
221:     def run_gc!
222:       @gc_request_countdown = gc_request_period
223:       GC.enable; GC.start; GC.disable
224:     end

[Source]

     # File vendor/rails/railties/lib/fcgi_handler.rb, line 149
149:     def with_signal_handler(signal)
150:       install_signal_handler(signal)
151:       yield
152:     ensure
153:       install_signal_handler(signal, 'DEFAULT')
154:     end

[Validate]