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puma--puma/lib/mongrel.rb

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require 'socket'
require 'http11'
require 'thread'
require 'stringio'
require 'mongrel/cgi'
require 'mongrel/handlers'
require 'mongrel/command'
require 'mongrel/tcphack'
require 'yaml'
# Mongrel module containing all of the classes (include C extensions) for running
# a Mongrel web server. It contains a minimalist HTTP server with just enough
# functionality to service web application requests fast as possible.
module Mongrel
class URIClassifier
# Returns the URIs that have been registered with this classifier so far.
# The URIs returned should not be modified as this will cause a memory leak.
# You can use this to inspect the contents of the URIClassifier.
def uris
@handler_map.keys
end
# Simply does an inspect that looks like a Hash inspect.
def inspect
@handler_map.inspect
end
end
# Used to stop the HttpServer via Thread.raise.
class StopServer < Exception
end
# Every standard HTTP code mapped to the appropriate message. These are
# used so frequently that they are placed directly in Mongrel for easy
# access rather than Mongrel::Const.
HTTP_STATUS_CODES = {
100 => 'Continue',
101 => 'Switching Protocols',
200 => 'OK',
201 => 'Created',
202 => 'Accepted',
203 => 'Non-Authoritative Information',
204 => 'No Content',
205 => 'Reset Content',
206 => 'Partial Content',
300 => 'Multiple Choices',
301 => 'Moved Permanently',
302 => 'Moved Temporarily',
303 => 'See Other',
304 => 'Not Modified',
305 => 'Use Proxy',
400 => 'Bad Request',
401 => 'Unauthorized',
402 => 'Payment Required',
403 => 'Forbidden',
404 => 'Not Found',
405 => 'Method Not Allowed',
406 => 'Not Acceptable',
407 => 'Proxy Authentication Required',
408 => 'Request Time-out',
409 => 'Conflict',
410 => 'Gone',
411 => 'Length Required',
412 => 'Precondition Failed',
413 => 'Request Entity Too Large',
414 => 'Request-URI Too Large',
415 => 'Unsupported Media Type',
500 => 'Internal Server Error',
501 => 'Not Implemented',
502 => 'Bad Gateway',
503 => 'Service Unavailable',
504 => 'Gateway Time-out',
505 => 'HTTP Version not supported'
}
# Frequently used constants when constructing requests or responses. Many times
# the constant just refers to a string with the same contents. Using these constants
# gave about a 3% to 10% performance improvement over using the strings directly.
# Symbols did not really improve things much compared to constants.
#
# While Mongrel does try to emulate the CGI/1.2 protocol, it does not use the REMOTE_IDENT,
# REMOTE_USER, or REMOTE_HOST parameters since those are either a security problem or
# too taxing on performance.
module Const
# This is the part of the path after the SCRIPT_NAME. URIClassifier will determine this.
PATH_INFO="PATH_INFO"
# This is the intial part that your handler is identified as by URIClassifier.
SCRIPT_NAME="SCRIPT_NAME"
# The original URI requested by the client. Passed to URIClassifier to build PATH_INFO and SCRIPT_NAME.
REQUEST_URI='REQUEST_URI'
MONGREL_VERSION="0.3.12"
# The standard empty 404 response for bad requests. Use Error4040Handler for custom stuff.
ERROR_404_RESPONSE="HTTP/1.1 404 Not Found\r\nConnection: close\r\nServer: #{MONGREL_VERSION}\r\n\r\nNOT FOUND"
CONTENT_LENGTH="CONTENT_LENGTH"
# A common header for indicating the server is too busy. Not used yet.
ERROR_503_RESPONSE="HTTP/1.1 503 Service Unavailable\r\n\r\nBUSY"
# The basic max request size we'll try to read.
CHUNK_SIZE=(16 * 1024)
end
# When a handler is found for a registered URI then this class is constructed
# and passed to your HttpHandler::process method. You should assume that
# *one* handler processes all requests. Included in the HttpReqeust is a
# HttpRequest.params Hash that matches common CGI params, and a HttpRequest.body
# which is a string containing the request body (raw for now).
#
# Mongrel really only supports small-ish request bodies right now since really
# huge ones have to be completely read off the wire and put into a string.
# Later there will be several options for efficiently handling large file
# uploads.
class HttpRequest
attr_reader :body, :params
# You don't really call this. It's made for you.
# Main thing it does is hook up the params, and store any remaining
# body data into the HttpRequest.body attribute.
def initialize(params, initial_body, socket)
@body = initial_body || ""
@params = params
@socket = socket
# now, if the initial_body isn't long enough for the content length we have to fill it
# TODO: adapt for big ass stuff by writing to a temp file
clen = params[Const::CONTENT_LENGTH].to_i
if @body.length < clen
@body << @socket.read(clen - @body.length)
end
end
def self.escape(s)
s.to_s.gsub(/([^ a-zA-Z0-9_.-]+)/n) {
'%'+$1.unpack('H2'*$1.size).join('%').upcase
}.tr(' ', '+')
end
def self.unescape(s)
s.tr('+', ' ').gsub(/((?:%[0-9a-fA-F]{2})+)/n){
[$1.delete('%')].pack('H*')
}
end
def self.query_parse(qs, d = '&;')
params = {}
(qs||'').split(/[#{d}] */n).inject(params) { |h,p|
k, v=unescape(p).split('=',2)
if cur = params[k]
if cur.class == Array
params[k] << v
else
params[k] = [cur, v]
end
else
params[k] = v
end
}
return params
end
end
# This class implements a simple way of constructing the HTTP headers dynamically
# via a Hash syntax. Think of it as a write-only Hash. Refer to HttpResponse for
# information on how this is used.
#
# One consequence of this write-only nature is that you can write multiple headers
# by just doing them twice (which is sometimes needed in HTTP), but that the normal
# semantics for Hash (where doing an insert replaces) is not there.
class HeaderOut
attr_reader :out
def initialize(out)
@out = out
end
# Simply writes "#{key}: #{value}" to an output buffer.
def[]=(key,value)
@out.write(key)
@out.write(": ")
@out.write(value)
@out.write("\r\n")
end
end
# Writes and controls your response to the client using the HTTP/1.1 specification.
# You use it by simply doing:
#
# response.start(200) do |head,out|
# head['Content-Type'] = 'text/plain'
# out.write("hello\n")
# end
#
# The parameter to start is the response code--which Mongrel will translate for you
# based on HTTP_STATUS_CODES. The head parameter is how you write custom headers.
# The out parameter is where you write your body. The default status code for
# HttpResponse.start is 200 so the above example is redundant.
#
# As you can see, it's just like using a Hash and as you do this it writes the proper
# header to the output on the fly. You can even intermix specifying headers and
# writing content. The HttpResponse class with write the things in the proper order
# once the HttpResponse.block is ended.
#
# You may also work the HttpResponse object directly using the various attributes available
# for the raw socket, body, header, and status codes. If you do this you're on your own.
# A design decision was made to force the client to not pipeline requests. HTTP/1.1
# pipelining really kills the performance due to how it has to be handled and how
# unclear the standard is. To fix this the HttpResponse gives a "Connection: close"
# header which forces the client to close right away. The bonus for this is that it
# gives a pretty nice speed boost to most clients since they can close their connection
# immediately.
#
# One additional caveat is that you don't have to specify the Content-length header
# as the HttpResponse will write this for you based on the out length.
class HttpResponse
attr_reader :socket
attr_reader :body
attr_reader :header
attr_reader :status
attr_writer :status
attr_reader :body_sent
attr_reader :header_sent
attr_reader :status_sent
def initialize(socket, filter = nil)
@socket = socket
@body = StringIO.new
@status = 404
@header = HeaderOut.new(StringIO.new)
@filter = filter
@body_sent = false
@header_sent = false
@status_sent = false
end
# Receives a block passing it the header and body for you to work with.
# When the block is finished it writes everything you've done to
# the socket in the proper order. This lets you intermix header and
# body content as needed. Handlers are able to modify pretty much
# any part of the request in the chain, and can stop further processing
# by simple passing "finalize=true" to the start method. By default
# all handlers run and then mongrel finalizes the request when they're
# all done.
def start(status=200, finalize=false)
@status = status.to_i
yield @header, @body
finished if finalize
end
# Primarily used in exception handling to reset the response output in order to write
# an alternative response. It will abort with an exception if you have already
# sent the header or the body. This is pretty catastrophic actually.
def reset
if @body_sent
raise "You have already sent the request body."
elsif @header_sent
raise "You have already sent the request headers."
else
@header.out.rewind
@body.rewind
end
end
def send_status
if not @status_sent
status = "HTTP/1.1 #{@status} #{HTTP_STATUS_CODES[@status]}\r\nContent-Length: #{@body.length}\r\nConnection: close\r\n"
@socket.write(status)
@status_sent = true
end
end
def send_header
if not @header_sent
@header.out.rewind
@socket.write(@header.out.read)
@socket.write("\r\n")
@header_sent = true
end
end
def send_body
if not @body_sent
@body.rewind
# connection: close is also added to ensure that the client does not pipeline.
@socket.write(@body.read)
@body_sent = true
end
end
def write(data)
@socket.write(data)
end
# This takes whatever has been done to header and body and then writes it in the
# proper format to make an HTTP/1.1 response.
def finished
send_status
send_header
send_body
end
def done
(@status_sent and @header_sent and @body_sent)
end
end
# This is the main driver of Mongrel, while the Mognrel::HttpParser and Mongrel::URIClassifier
# make up the majority of how the server functions. It's a very simple class that just
# has a thread accepting connections and a simple HttpServer.process_client function
# to do the heavy lifting with the IO and Ruby.
#
# You use it by doing the following:
#
# server = HttpServer.new("0.0.0.0", 3000)
# server.register("/stuff", MyNifterHandler.new)
# server.run.join
#
# The last line can be just server.run if you don't want to join the thread used.
# If you don't though Ruby will mysteriously just exit on you.
#
# Ruby's thread implementation is "interesting" to say the least. Experiments with
# *many* different types of IO processing simply cannot make a dent in it. Future
# releases of Mongrel will find other creative ways to make threads faster, but don't
# hold your breath until Ruby 1.9 is actually finally useful.
class HttpServer
attr_reader :acceptor
attr_reader :workers
attr_reader :classifier
# Creates a working server on host:port (strange things happen if port isn't a Number).
# Use HttpServer::run to start the server and HttpServer.acceptor.join to
# join the thread that's processing incoming requests on the socket.
#
# The num_processors optional argument is the maximum number of concurrent
# processors to accept, anything over this is closed immediately to maintain
# server processing performance. This may seem mean but it is the most efficient
# way to deal with overload. Other schemes involve still parsing the client's request
# which defeats the point of an overload handling system.
#
# The timeout parameter is a sleep timeout (in hundredths of a second) that is placed between
# socket.accept calls in order to give the server a cheap throttle time. It defaults to 0 and
# actually if it is 0 then the sleep is not done at all.
def initialize(host, port, num_processors=(2**30-1), timeout=0)
@socket = TCPServer.new(host, port)
@classifier = URIClassifier.new
@host = host
@port = port
@workers = ThreadGroup.new
@timeout = timeout
@num_processors = num_processors
end
# Does the majority of the IO processing. It has been written in Ruby using
# about 7 different IO processing strategies and no matter how it's done
# the performance just does not improve. It is currently carefully constructed
# to make sure that it gets the best possible performance, but anyone who
# thinks they can make it faster is more than welcome to take a crack at it.
def process_client(client)
begin
parser = HttpParser.new
params = {}
data = client.readpartial(Const::CHUNK_SIZE)
while true
nread = parser.execute(params, data)
if parser.finished?
script_name, path_info, handlers = @classifier.resolve(params[Const::REQUEST_URI])
if handlers
params[Const::PATH_INFO] = path_info
params[Const::SCRIPT_NAME] = script_name
request = HttpRequest.new(params, data[nread ... data.length], client)
response = HttpResponse.new(client)
handlers.each do |handler|
handler.process(request, response)
break if response.done
end
if not response.done
response.finished
end
else
client.write(Const::ERROR_404_RESPONSE)
end
break #done
else
# gotta stream and read again until we can get the parser to be character safe
# TODO: make this more efficient since this means we're parsing a lot repeatedly
parser.reset
data << client.readpartial(Const::CHUNK_SIZE)
end
end
rescue EOFError
# ignored
rescue Errno::ECONNRESET
# ignored
rescue Errno::EPIPE
# ignored
rescue => details
STDERR.puts "ERROR(#{details.class}): #{details}"
STDERR.puts details.backtrace.join("\n")
ensure
client.close
end
end
# Used internally to kill off any worker threads that have taken too long
# to complete processing. Only called if there are too many processors
# currently servicing.
def reap_dead_workers(worker_list)
mark = Time.now
worker_list.each do |w|
if mark - w[:started_on] > 10 * @timeout
STDERR.puts "Thread #{w.inspect} is too old, killing."
w.raise(StopServer.new("Timed out thread."))
end
end
end
# Runs the thing. It returns the thread used so you can "join" it. You can also
# access the HttpServer::acceptor attribute to get the thread later.
def run
BasicSocket.do_not_reverse_lookup=true
@acceptor = Thread.new do
while true
begin
client = @socket.accept
worker_list = @workers.list
if worker_list.length >= @num_processors
STDERR.puts "Server overloaded with #{worker_list.length} processors (#@num_processors max). Dropping connection."
client.close
reap_dead_workers(worker_list)
else
thread = Thread.new do
process_client(client)
end
thread[:started_on] = Time.now
thread.priority=1
@workers.add(thread)
sleep @timeout/100 if @timeout > 0
end
rescue StopServer
STDERR.puts "Server stopped. Exiting."
@socket.close if not @socket.closed?
break
rescue Errno::EMFILE
STDERR.puts "Too many open files. Try increasing ulimits."
sleep 0.5
end
end
# now that processing is done we feed enough false onto the request queue to get
# each processor to exit and stop processing.
# finally we wait until the queue is empty
while @workers.list.length > 0
STDERR.puts "Shutdown waiting for #{@workers.list.length} requests" if @workers.list.length > 0
sleep 1
end
end
return @acceptor
end
# Simply registers a handler with the internal URIClassifier. When the URI is
# found in the prefix of a request then your handler's HttpHandler::process method
# is called. See Mongrel::URIClassifier#register for more information.
def register(uri, handler)
script_name, path_info, handlers = @classifier.resolve(uri)
if not handlers
@classifier.register(uri, [handler])
else
if path_info.length == 0 or (script_name == "/" and path_info == "/")
handlers << handler
else
@classifier.register(uri, [handler])
end
end
end
# Removes any handlers registered at the given URI. See Mongrel::URIClassifier#unregister
# for more information. Remember this removes them *all* so the entire
# processing chain goes away.
def unregister(uri)
@classifier.unregister(uri)
end
# Stops the acceptor thread and then causes the worker threads to finish
# off the request queue before finally exiting.
def stop
stopper = Thread.new do
exc = StopServer.new
@acceptor.raise(exc)
end
stopper.priority = 10
end
end
# Implements a simple DSL for configuring a Mongrel server for your
# purposes. More used by framework implementers to setup Mongrel
# how they like, but could be used by regular folks to add more things
# to an existing mongrel configuration.
#
# It is used like this:
#
# require 'mongrel'
# config = Mongrel::Configurator.new :host => "127.0.0.1" do
# listener :port => 3000 do
# uri "/app", :handler => Mongrel::DirHandler.new(".", load_mime_map("mime.yaml"))
# end
# run
# end
#
# This will setup a simple DirHandler at the current directory and load additional
# mime types from mimy.yaml. The :host => "127.0.0.1" is actually not
# specific to the servers but just a hash of default parameters that all
# server or uri calls receive.
#
# When you are inside the block after Mongrel::Configurator.new you can simply
# call functions that are part of Configurator (like server, uri, daemonize, etc)
# without having to refer to anything else. You can also call these functions on
# the resulting object directly for additional configuration.
#
# A major thing about Configurator is that it actually lets you configure
# multiple listeners for any hosts and ports you want. These are kept in a
# map config.listeners so you can get to them.
class Configurator
attr_reader :listeners
attr_reader :defaults
attr_reader :needs_restart
# You pass in initial defaults and then a block to continue configuring.
def initialize(defaults={}, &blk)
@listeners = {}
@defaults = defaults
@needs_restart = false
if blk
cloaker(&blk).bind(self).call
end
end
# Do not call this. You were warned.
def cloaker &blk
(class << self; self; end).class_eval do
define_method :cloaker_, &blk
meth = instance_method( :cloaker_ )
remove_method :cloaker_
meth
end
end
# This will resolve the given options against the defaults.
# Normally just used internally.
def resolve_defaults(options)
options.merge(@defaults)
end
# Starts a listener block. This is the only one that actually takes
# a block and then you make Configurator.uri calls in order to setup
# your URIs and handlers. If you write your Handlers as GemPlugins
# then you can use load_plugins and plugin to load them.
#
# It expects the following options (or defaults):
#
# * :host => Host name to bind.
# * :port => Port to bind.
# * :num_processors => The maximum number of concurrent threads allowed. (950 default)
# * :timeout => 1/100th of a second timeout between requests. (10 is 1/10th, 0 is not timeout)
#
def listener(options={},&blk)
ops = resolve_defaults(options)
ops[:num_processors] ||= 950
ops[:timeout] ||= 0
@listener = Mongrel::HttpServer.new(ops[:host], ops[:port].to_i, ops[:num_processors].to_i, ops[:timeout].to_i)
@listener_name = "#{ops[:host]}:#{ops[:port]}"
@listeners[@listener_name] = @listener
if blk
cloaker(&blk).bind(self).call
end
# all done processing this listener setup
@listener = nil
@listener_name = nil
end
# Called inside a Configurator.listener block in order to
# add URI->handler mappings for that listener. Use this as
# many times as you like. It expects the following options
# or defaults:
#
# * :handler => Handler to use for this location.
def uri(location, options={})
ops = resolve_defaults(options)
@listener.register(location, ops[:handler])
end
# Daemonizes the current Ruby script turning all the
# listeners into an actual "server" or detached process.
# You must call this *before* frameworks that open files
# as otherwise the files will be closed by this function.
#
# Does not work for Win32 systems (the call is silently ignored).
#
# Requires the following options or defaults:
#
# * :cwd => Directory to change to.
# * :log_file => Where to write STDOUT and STDERR.
# * :pid_file => Where to write the process ID.
#
# It is safe to call this on win32 as it will only require daemons
# if NOT win32.
def daemonize(options={})
ops = resolve_defaults(options)
# save this for later since daemonize will hose it
if RUBY_PLATFORM !~ /mswin/
require 'daemons/daemonize'
Daemonize.daemonize(log_file=File.join(ops[:cwd], ops[:log_file]))
# change back to the original starting directory
Dir.chdir(ops[:cwd])
open(ops[:pid_file],"w") {|f| f.write(Process.pid) }
else
log "WARNING: Win32 does not support daemon mode."
end
end
# Uses the GemPlugin system to easily load plugins based on their
# gem dependencies. You pass in either an :includes => [] or
# :excludes => [] setting listing the names of plugins to include
# or exclude from the loading.
def load_plugins(options={})
ops = resolve_defaults(options)
load_settings = {}
if ops[:includes]
ops[:includes].each do |plugin|
load_settings[plugin] = GemPlugin::INCLUDE
end
end
if ops[:excludes]
ops[:excludes].each do |plugin|
load_settings[plugin] = GemPlugin::EXCLUDE
end
end
GemPlugin::Manager.instance.load(load_settings)
end
# Easy way to load a YAML file and apply default settings.
def load_yaml(file, default={})
default.merge(YAML.load_file(file))
end
# Loads the MIME map file and checks that it is correct
# on loading. This is commonly passed to Mongrel::DirHandler
# or any framework handler that uses DirHandler to serve files.
# You can also include a set of default MIME types as additional
# settings. See Mongrel::DirHandler for how the MIME types map
# is organized.
def load_mime_map(file, mime={})
# configure any requested mime map
log "Loading additional MIME types from #{file}"
mime = load_yaml(file, mime)
# check all the mime types to make sure they are the right format
mime.each {|k,v| log "WARNING: MIME type #{k} must start with '.'" if k.index(".") != 0 }
return mime
end
# Loads and creates a plugin for you based on the given
# name and configured with the selected options. The options
# are merged with the defaults prior to passing them in.
def plugin(name, options={})
ops = resolve_defaults(options)
GemPlugin::Manager.instance.create(name, ops)
end
# Works like a meta run method which goes through all the
# configured listeners. Use the Configurator.join method
# to prevent Ruby from exiting until each one is done.
def run
@listeners.each {|name,s|
log "Running #{name} listener."
s.run
}
end
# Calls .stop on all the configured listeners so they
# stop processing requests (gracefully).
def stop
@listeners.each {|name,s|
log "Stopping #{name} listener."
s.stop
}
end
# This method should actually be called *outside* of the
# Configurator block so that you can control it. In otherwords
# do it like: config.join.
def join
@listeners.values.each {|s| s.acceptor.join }
end
# Calling this before you register your URIs to the given location
# will setup a set of handlers that log open files, objects, and the
# parameters for each request. This helps you track common problems
# found in Rails applications that are either slow or become unresponsive
# after a little while.
def debug(location)
require 'mongrel/debug'
ObjectTracker.configure
MongrelDbg.configure
MongrelDbg.begin_trace :objects
MongrelDbg.begin_trace :rails
MongrelDbg.begin_trace :files
uri location, :handler => plugin("/handlers/requestlog::files")
uri location, :handler => plugin("/handlers/requestlog::objects")
uri location, :handler => plugin("/handlers/requestlog::params")
end
# Sets up the standard signal handlers that are used on most Ruby
# It only configures if the platform is not win32 and doesn't do
# a HUP signal since this is typically framework specific.
#
# Requires a :pid_file option to indicate a file to delete.
# It sets the MongrelConfig.needs_restart attribute if
# the start command should reload. It's up to you to detect this
# and do whatever is needed for a "restart".
#
# This command is safely ignored if the platform is win32 (with a warning)
def setup_signals(options={})
ops = resolve_defaults(options)
if RUBY_PLATFORM !~ /mswin/
# graceful shutdown
trap("TERM") {
log "TERM signal received."
stop
File.unlink ops[:pid_file] if File.exist?(ops[:pid_file])
}
# restart
trap("USR2") {
log "USR2 signal received."
stop
File.unlink ops[:pid_file] if File.exist?(ops[:pid_file])
@needs_restart = true
}
trap("INT") {
log "INT signal received."
stop
File.unlink ops[:pid_file] if File.exist?(ops[:pid_file])
@needs_restart = false
}
log "Signals ready. TERM => stop. USR2 => restart. INT => stop (no restart)."
else
log "WARNING: Win32 does not have signals support."
end
end
# Logs a simple message to STDERR (or the mongrel log if in daemon mode).
def log(msg)
STDERR.print "** ", msg, "\n"
end
end
end