› Protocol::HTTP › Source › Protocol › HTTP › Body › ZStream

class ZStream

A body which compresses or decompresses the contents using the DEFLATE or GZIP algorithm.

Definitions

DEFAULT_LEVEL = 7

The default compression level.

DEFLATE = -Zlib::MAX_WBITS

The DEFLATE window size.

GZIP = Zlib::MAX_WBITS | 16

The GZIP window size.

ENCODINGS = {...}

The supported encodings.

Implementation

 
ENCODINGS = {
	"deflate" => DEFLATE,
	"gzip" => GZIP,
}

def initialize(body, stream)

Initialize the body with the given stream.

Signature
parameter　body　Readable

the body to wrap.

parameter　stream　Zlib::Deflate | Zlib::Inflate

the stream to use for compression or decompression.

Implementation

 
def initialize(body, stream)
	super(body)
	
	@stream = stream
	
	@input_length = 0
	@output_length = 0
end

def close(error = nil)

Close the stream.

Signature
parameter　error　Exception | Nil

the error that caused the stream to be closed.

Implementation

 
def close(error = nil)
	if stream = @stream
		@stream = nil
		stream.close unless stream.closed?
	end
	
	super
end

def length

The length of the output, if known. Generally, this is not known due to the nature of compression.

Implementation

 
def length
	# We don't know the length of the output until after it's been compressed.
	nil
end

attr :input_length

Signature
attribute　Integer

input_length the total number of bytes read from the input.

attr :output_length

Signature
attribute　Integer

output_length the total number of bytes written to the output.

def ratio

The compression ratio, according to the input and output lengths.

Signature
returns　Float

the compression ratio, e.g. 0.5 for 50% compression.

Implementation

 
def ratio
	if @input_length != 0
		@output_length.to_f / @input_length.to_f
	else
		1.0
	end
end

def inspect

Inspect the body, including the compression ratio.

Signature
returns　String

a string representation of the body.

Implementation

 
def inspect
	"#{super} | \#<#{self.class} #{(ratio*100).round(2)}%>"
end