97 lines
2.7 KiB
Ruby
97 lines
2.7 KiB
Ruby
require "zlib"
|
|
require "stringio"
|
|
require "time" # for Time.httpdate
|
|
require 'rack/utils'
|
|
|
|
module Rack
|
|
class Deflater
|
|
def initialize(app)
|
|
@app = app
|
|
end
|
|
|
|
def call(env)
|
|
status, headers, body = @app.call(env)
|
|
headers = Utils::HeaderHash.new(headers)
|
|
|
|
# Skip compressing empty entity body responses and responses with
|
|
# no-transform set.
|
|
if Utils::STATUS_WITH_NO_ENTITY_BODY.include?(status) ||
|
|
headers['Cache-Control'].to_s =~ /\bno-transform\b/
|
|
return [status, headers, body]
|
|
end
|
|
|
|
request = Request.new(env)
|
|
|
|
encoding = Utils.select_best_encoding(%w(gzip deflate identity),
|
|
request.accept_encoding)
|
|
|
|
# Set the Vary HTTP header.
|
|
vary = headers["Vary"].to_s.split(",").map { |v| v.strip }
|
|
unless vary.include?("*") || vary.include?("Accept-Encoding")
|
|
headers["Vary"] = vary.push("Accept-Encoding").join(",")
|
|
end
|
|
|
|
case encoding
|
|
when "gzip"
|
|
headers['Content-Encoding'] = "gzip"
|
|
headers.delete('Content-Length')
|
|
mtime = headers.key?("Last-Modified") ?
|
|
Time.httpdate(headers["Last-Modified"]) : Time.now
|
|
[status, headers, GzipStream.new(body, mtime)]
|
|
when "deflate"
|
|
headers['Content-Encoding'] = "deflate"
|
|
headers.delete('Content-Length')
|
|
[status, headers, DeflateStream.new(body)]
|
|
when "identity"
|
|
[status, headers, body]
|
|
when nil
|
|
message = "An acceptable encoding for the requested resource #{request.fullpath} could not be found."
|
|
[406, {"Content-Type" => "text/plain", "Content-Length" => message.length.to_s}, [message]]
|
|
end
|
|
end
|
|
|
|
class GzipStream
|
|
def initialize(body, mtime)
|
|
@body = body
|
|
@mtime = mtime
|
|
end
|
|
|
|
def each(&block)
|
|
@writer = block
|
|
gzip =::Zlib::GzipWriter.new(self)
|
|
gzip.mtime = @mtime
|
|
@body.each { |part| gzip.write(part) }
|
|
@body.close if @body.respond_to?(:close)
|
|
gzip.close
|
|
@writer = nil
|
|
end
|
|
|
|
def write(data)
|
|
@writer.call(data)
|
|
end
|
|
end
|
|
|
|
class DeflateStream
|
|
DEFLATE_ARGS = [
|
|
Zlib::DEFAULT_COMPRESSION,
|
|
# drop the zlib header which causes both Safari and IE to choke
|
|
-Zlib::MAX_WBITS,
|
|
Zlib::DEF_MEM_LEVEL,
|
|
Zlib::DEFAULT_STRATEGY
|
|
]
|
|
|
|
def initialize(body)
|
|
@body = body
|
|
end
|
|
|
|
def each
|
|
deflater = ::Zlib::Deflate.new(*DEFLATE_ARGS)
|
|
@body.each { |part| yield deflater.deflate(part) }
|
|
@body.close if @body.respond_to?(:close)
|
|
yield deflater.finish
|
|
nil
|
|
end
|
|
end
|
|
end
|
|
end
|