Class: Rack::Deflater::GzipStream

Inherits:
Object
  • Object
show all
Defined in:
lib/rack/deflater.rb

Overview

Body class used for gzip encoded responses.

Constant Summary collapse

BUFFER_LENGTH =
128 * 1_024

Instance Method Summary collapse

Constructor Details

#initialize(body, mtime, sync) ⇒ GzipStream

Initialize the gzip stream. Arguments:

body

Response body to compress with gzip

mtime

The modification time of the body, used to set the modification time in the gzip header.

sync

Whether to flush each gzip chunk as soon as it is ready.


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# File 'lib/rack/deflater.rb', line 92

def initialize(body, mtime, sync)
  @body = body
  @mtime = mtime
  @sync = sync
end

Instance Method Details

#closeObject

Close the original body if possible.


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# File 'lib/rack/deflater.rb', line 128

def close
  @body.close if @body.respond_to?(:close)
end

#each(&block) ⇒ Object

Yield gzip compressed strings to the given block.


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# File 'lib/rack/deflater.rb', line 99

def each(&block)
  @writer = block
  gzip = ::Zlib::GzipWriter.new(self)
  gzip.mtime = @mtime if @mtime
  # @body.each is equivalent to @body.gets (slow)
  if @body.is_a? ::File # XXX: Should probably be ::IO
    while part = @body.read(BUFFER_LENGTH)
      gzip.write(part)
      gzip.flush if @sync
    end
  else
    @body.each { |part|
      # Skip empty strings, as they would result in no output,
      # and flushing empty parts would raise Zlib::BufError.
      next if part.empty?
      gzip.write(part)
      gzip.flush if @sync
    }
  end
ensure
  gzip.finish
end

#write(data) ⇒ Object

Call the block passed to #each with the gzipped data.


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# File 'lib/rack/deflater.rb', line 123

def write(data)
  @writer.call(data)
end