1
0
Fork 0
mirror of https://github.com/puma/puma.git synced 2022-11-09 13:48:40 -05:00
puma--puma/lib/mongrel/handlers.rb
evanweaver 467fcb5d8b avoid warnings on 1.8.6, at least
git-svn-id: svn+ssh://rubyforge.org/var/svn/mongrel/trunk@625 19e92222-5c0b-0410-8929-a290d50e31e9
2007-09-24 16:37:26 +00:00

454 lines
16 KiB
Ruby

# Copyright (c) 2005 Zed A. Shaw
# You can redistribute it and/or modify it under the same terms as Ruby.
#
# Additional work donated by contributors. See http://mongrel.rubyforge.org/attributions.html
# for more information.
require 'mongrel/stats'
require 'zlib'
require 'yaml'
module Mongrel
# You implement your application handler with this. It's very light giving
# just the minimum necessary for you to handle a request and shoot back
# a response. Look at the HttpRequest and HttpResponse objects for how
# to use them.
#
# This is used for very simple handlers that don't require much to operate.
# More extensive plugins or those you intend to distribute as GemPlugins
# should be implemented using the HttpHandlerPlugin mixin.
#
class HttpHandler
attr_reader :request_notify
attr_accessor :listener
# This will be called by Mongrel if HttpHandler.request_notify set to *true*.
# You only get the parameters for the request, with the idea that you'd "bound"
# the beginning of the request processing and the first call to process.
def request_begins(params)
end
# Called by Mongrel for each IO chunk that is received on the request socket
# from the client, allowing you to track the progress of the IO and monitor
# the input. This will be called by Mongrel only if HttpHandler.request_notify
# set to *true*.
def request_progress(params, clen, total)
end
def process(request, response)
end
end
# This is used when your handler is implemented as a GemPlugin.
# The plugin always takes an options hash which you can modify
# and then access later. They are stored by default for
# the process method later.
module HttpHandlerPlugin
attr_reader :options
attr_reader :request_notify
attr_accessor :listener
def request_begins(params)
end
def request_progress(params, clen, total)
end
def initialize(options={})
@options = options
@header_only = false
end
def process(request, response)
end
end
# The server normally returns a 404 response if an unknown URI is requested, but it
# also returns a lame empty message. This lets you do a 404 response
# with a custom message for special URIs.
class Error404Handler < HttpHandler
# Sets the message to return. This is constructed once for the handler
# so it's pretty efficient.
def initialize(msg)
@response = Const::ERROR_404_RESPONSE + msg
end
# Just kicks back the standard 404 response with your special message.
def process(request, response)
response.socket.write(@response)
end
end
# Serves the contents of a directory. You give it the path to the root
# where the files are located, and it tries to find the files based on
# the PATH_INFO inside the directory. If the requested path is a
# directory then it returns a simple directory listing.
#
# It does a simple protection against going outside it's root path by
# converting all paths to an absolute expanded path, and then making sure
# that the final expanded path includes the root path. If it doesn't
# than it simply gives a 404.
#
# The default content type is "text/plain; charset=ISO-8859-1" but you
# can change it anything you want using the DirHandler.default_content_type
# attribute.
class DirHandler < HttpHandler
attr_accessor :default_content_type
attr_reader :path
MIME_TYPES_FILE = "mime_types.yml"
MIME_TYPES = YAML.load_file(File.join(File.dirname(__FILE__), MIME_TYPES_FILE))
ONLY_HEAD_GET="Only HEAD and GET allowed.".freeze
# You give it the path to the directory root and an (optional)
def initialize(path, listing_allowed=true, index_html="index.html")
@path = File.expand_path(path)
@listing_allowed=listing_allowed
@index_html = index_html
@default_content_type = "application/octet-stream".freeze
end
# Checks if the given path can be served and returns the full path (or nil if not).
def can_serve(path_info)
req_path = File.expand_path(File.join(@path,HttpRequest.unescape(path_info)), @path)
if req_path.index(@path) == 0 and File.exist? req_path
# it exists and it's in the right location
if File.directory? req_path
# the request is for a directory
index = File.join(req_path, @index_html)
if File.exist? index
# serve the index
return index
elsif @listing_allowed
# serve the directory
return req_path
else
# do not serve anything
return nil
end
else
# it's a file and it's there
return req_path
end
else
# does not exist or isn't in the right spot
return nil
end
end
# Returns a simplistic directory listing if they're enabled, otherwise a 403.
# Base is the base URI from the REQUEST_URI, dir is the directory to serve
# on the file system (comes from can_serve()), and response is the HttpResponse
# object to send the results on.
def send_dir_listing(base, dir, response)
# take off any trailing / so the links come out right
base = HttpRequest.unescape(base)
base.chop! if base[-1] == "/"[-1]
if @listing_allowed
response.start(200) do |head,out|
head[Const::CONTENT_TYPE] = "text/html"
out << "<html><head><title>Directory Listing</title></head><body>"
Dir.entries(dir).each do |child|
next if child == "."
out << "<a href=\"#{base}/#{ HttpRequest.escape(child)}\">"
out << (child == ".." ? "Up to parent.." : child)
out << "</a><br/>"
end
out << "</body></html>"
end
else
response.start(403) do |head,out|
out.write("Directory listings not allowed")
end
end
end
# Sends the contents of a file back to the user. Not terribly efficient since it's
# opening and closing the file for each read.
def send_file(req_path, request, response, header_only=false)
stat = File.stat(req_path)
# Set the last modified times as well and etag for all files
mtime = stat.mtime
# Calculated the same as apache, not sure how well the works on win32
etag = Const::ETAG_FORMAT % [mtime.to_i, stat.size, stat.ino]
modified_since = request.params[Const::HTTP_IF_MODIFIED_SINCE]
none_match = request.params[Const::HTTP_IF_NONE_MATCH]
# test to see if this is a conditional request, and test if
# the response would be identical to the last response
same_response = case
when modified_since && !last_response_time = Time.httpdate(modified_since) rescue nil : false
when modified_since && last_response_time > Time.now : false
when modified_since && mtime > last_response_time : false
when none_match && none_match == '*' : false
when none_match && !none_match.strip.split(/\s*,\s*/).include?(etag) : false
else modified_since || none_match # validation successful if we get this far and at least one of the header exists
end
header = response.header
header[Const::ETAG] = etag
if same_response
response.start(304) {}
else
# first we setup the headers and status then we do a very fast send on the socket directly
response.status = 200
header[Const::LAST_MODIFIED] = mtime.httpdate
# set the mime type from our map based on the ending
dot_at = req_path.rindex('.')
if dot_at
header[Const::CONTENT_TYPE] = MIME_TYPES[req_path[dot_at .. -1]] || @default_content_type
else
header[Const::CONTENT_TYPE] = @default_content_type
end
# send a status with out content length
response.send_status(stat.size)
response.send_header
if not header_only
response.send_file(req_path, stat.size < Const::CHUNK_SIZE * 2)
end
end
end
# Process the request to either serve a file or a directory listing
# if allowed (based on the listing_allowed parameter to the constructor).
def process(request, response)
req_method = request.params[Const::REQUEST_METHOD] || Const::GET
req_path = can_serve request.params[Const::PATH_INFO]
if not req_path
# not found, return a 404
response.start(404) do |head,out|
out << "File not found"
end
else
begin
if File.directory? req_path
send_dir_listing(request.params[Const::REQUEST_URI], req_path, response)
elsif req_method == Const::HEAD
send_file(req_path, request, response, true)
elsif req_method == Const::GET
send_file(req_path, request, response, false)
else
response.start(403) {|head,out| out.write(ONLY_HEAD_GET) }
end
rescue => details
STDERR.puts "Error sending file #{req_path}: #{details}"
end
end
end
# There is a small number of default mime types for extensions, but
# this lets you add any others you'll need when serving content.
def DirHandler::add_mime_type(extension, type)
MIME_TYPES[extension] = type
end
end
# When added to a config script (-S in mongrel_rails) it will
# look at the client's allowed response types and then gzip
# compress anything that is going out.
#
# Valid option is :always_deflate => false which tells the handler to
# deflate everything even if the client can't handle it.
class DeflateFilter < HttpHandler
include Zlib
HTTP_ACCEPT_ENCODING = "HTTP_ACCEPT_ENCODING"
def initialize(ops={})
@options = ops
@always_deflate = ops[:always_deflate] || false
end
def process(request, response)
accepts = request.params[HTTP_ACCEPT_ENCODING]
# only process if they support compression
if @always_deflate or (accepts and (accepts.include? "deflate" and not response.body_sent))
response.header["Content-Encoding"] = "deflate"
response.body = deflate(response.body)
end
end
private
def deflate(stream)
deflater = Deflate.new(
DEFAULT_COMPRESSION,
# drop the zlib header which causes both Safari and IE to choke
-MAX_WBITS,
DEF_MEM_LEVEL,
DEFAULT_STRATEGY)
stream.rewind
gzout = StringIO.new(deflater.deflate(stream.read, FINISH))
stream.close
gzout.rewind
gzout
end
end
# Implements a few basic statistics for a particular URI. Register it anywhere
# you want in the request chain and it'll quickly gather some numbers for you
# to analyze. It is pretty fast, but don't put it out in production.
#
# You should pass the filter to StatusHandler as StatusHandler.new(:stats_filter => stats).
# This lets you then hit the status URI you want and get these stats from a browser.
#
# StatisticsFilter takes an option of :sample_rate. This is a number that's passed to
# rand and if that number gets hit then a sample is taken. This helps reduce the load
# and keeps the statistics valid (since sampling is a part of how they work).
#
# The exception to :sample_rate is that inter-request time is sampled on every request.
# If this wasn't done then it wouldn't be accurate as a measure of time between requests.
class StatisticsFilter < HttpHandler
attr_reader :stats
def initialize(ops={})
@sample_rate = ops[:sample_rate] || 300
@processors = Mongrel::Stats.new("processors")
@reqsize = Mongrel::Stats.new("request Kb")
@headcount = Mongrel::Stats.new("req param count")
@respsize = Mongrel::Stats.new("response Kb")
@interreq = Mongrel::Stats.new("inter-request time")
end
def process(request, response)
if rand(@sample_rate)+1 == @sample_rate
@processors.sample(listener.workers.list.length)
@headcount.sample(request.params.length)
@reqsize.sample(request.body.length / 1024.0)
@respsize.sample((response.body.length + response.header.out.length) / 1024.0)
end
@interreq.tick
end
def dump
"#{@processors.to_s}\n#{@reqsize.to_s}\n#{@headcount.to_s}\n#{@respsize.to_s}\n#{@interreq.to_s}"
end
end
# The :stats_filter is basically any configured stats filter that you've added to this same
# URI. This lets the status handler print out statistics on how Mongrel is doing.
class StatusHandler < HttpHandler
def initialize(ops={})
@stats = ops[:stats_filter]
end
def table(title, rows)
results = "<table border=\"1\"><tr><th colspan=\"#{rows[0].length}\">#{title}</th></tr>"
rows.each do |cols|
results << "<tr>"
cols.each {|col| results << "<td>#{col}</td>" }
results << "</tr>"
end
results + "</table>"
end
def describe_listener
results = ""
results << "<h1>Listener #{listener.host}:#{listener.port}</h1>"
results << table("settings", [
["host",listener.host],
["port",listener.port],
["throttle",listener.throttle],
["timeout",listener.timeout],
["workers max",listener.num_processors],
])
if @stats
results << "<h2>Statistics</h2><p>N means the number of samples, pay attention to MEAN, SD, MIN and MAX."
results << "<pre>#{@stats.dump}</pre>"
end
results << "<h2>Registered Handlers</h2>"
uris = listener.classifier.handler_map
results << table("handlers", uris.map {|uri,handlers|
[uri,
"<pre>" +
handlers.map {|h| h.class.to_s }.join("\n") +
"</pre>"
]
})
results
end
def process(request, response)
response.start do |head,out|
out.write <<-END
<html><body><title>Mongrel Server Status</title>
#{describe_listener}
</body></html>
END
end
end
end
# This handler allows you to redirect one url to another.
# You can use it like String#gsub, where the string is the REQUEST_URI.
# REQUEST_URI is the full path with GET parameters.
#
# Eg. /test/something?help=true&disclaimer=false
#
# == Examples
#
# h = Mongrel::HttpServer.new('0.0.0.0')
# h.register '/test', Mongrel::RedirectHandler.new('/to/there') # simple
# h.register '/to', Mongrel::RedirectHandler.new(/t/, 'w') # regexp
# # and with a block
# h.register '/hey', Mongrel::RedirectHandler.new(/(\w+)/) { |match| ... }
#
class RedirectHandler < Mongrel::HttpHandler
# You set the rewrite rules when building the object.
#
# pattern => What to look for or replacement if used alone
#
# replacement, block => One of them is used to replace the found text
def initialize(pattern, replacement = nil, &block)
unless replacement or block
@pattern, @replacement = nil, pattern
else
@pattern, @replacement, @block = pattern, replacement, block
end
end
# Process the request and return a redirect response
def process(request, response)
unless @pattern
response.socket.write(Mongrel::Const::REDIRECT % @replacement)
else
if @block
new_path = request.params['REQUEST_URI'].gsub(@pattern, &@block)
else
new_path = request.params['REQUEST_URI'].gsub(@pattern, @replacement)
end
response.socket.write(Mongrel::Const::REDIRECT % new_path)
end
end
end
end