Class: HTTPX::Channel

Inherits:
Object
  • Object
show all
Extended by:
Forwardable
Includes:
Callbacks, Loggable, Registry
Defined in:
lib/httpx/channel.rb

Overview

The Channel entity can be watched for IO events.

It contains the io object to read/write from, and knows what to do when it can.

It defers connecting until absolutely necessary. Connection should be triggered from the IO selector (until then, any request will be queued).

A channel boots up its parser after connection is established. All pending requests will be redirected there after connection.

A channel can be prevented from closing by the parser, that is, if there are pending requests. This will signal that the channel was prematurely closed, due to a possible number of conditions:

  • Remote peer closed the connection ("Connection: close");
  • Remote peer doesn't support pipelining;

A channel may also route requests for a different host for which the io was connected to, provided that the IP is the same and the port and scheme as well. This will allow to share the same socket to send HTTP/2 requests to different hosts. TODO: For this to succeed, the certificates sent by the servers to the client must be identical (or match both hosts).

Direct Known Subclasses

ProxyChannel

Defined Under Namespace

Classes: HTTP1, HTTP2

Constant Summary collapse

BUFFER_SIZE = 
1 << 14

Constants included from Registry

Registry::Error

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Callbacks

#emit, #on, #once

Methods included from Loggable

#log

Methods included from Registry

extended, included

Constructor Details

#initialize(io, options) ⇒ Channel

Returns a new instance of Channel.



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# File 'lib/httpx/channel.rb', line 61

def initialize(io, options)
  @io = io
  @options = Options.new(options)
  @window_size = @options.window_size
  @read_buffer = Buffer.new(BUFFER_SIZE)
  @write_buffer = Buffer.new(BUFFER_SIZE)
  @pending = []
  @state = :idle
end

Class Method Details

.by(uri, options) ⇒ Object 



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# File 'lib/httpx/channel.rb', line 44

def by(uri, options)
  io = case uri.scheme
       when "http"
         IO.registry("tcp").new(uri.host, uri.port, options)
       when "https"
         IO.registry("ssl").new(uri.host, uri.port, options)
       else
         raise Error, "#{uri}: #{uri.scheme}: unrecognized channel"
  end
  new(io, options)
end

Instance Method Details

#call ⇒ Object 



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# File 'lib/httpx/channel.rb', line 122

def call
  case @state
  when :closed
    return
  when :closing
    dwrite
    transition(:closed)
    emit(:close)
  when :open
    consume
  end
  nil
end

#close ⇒ Object 



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# File 'lib/httpx/channel.rb', line 103

def close
  @parser.close if @parser
  transition(:closing)
end

#interests ⇒ Object 



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# File 'lib/httpx/channel.rb', line 84

def interests
  return :w if @state == :idle
  readable = !@read_buffer.full?
  writable = !@write_buffer.empty?
  if readable
    writable ? :rw : :r
  else
    writable ? :w : :r
  end
end

#match?(uri) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/httpx/channel.rb', line 71

def match?(uri)
  return false if @state == :closing
  ips = begin
    Resolv.getaddresses(uri.host)
  rescue StandardError
    [uri.host]
  end

  ips.include?(@io.ip) &&
    uri.port == @io.port &&
    uri.scheme == @io.scheme
end

#reset ⇒ Object 



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# File 'lib/httpx/channel.rb', line 108

def reset
  transition(:closing)
  transition(:closed)
  emit(:close)
end

#send(request, **args) ⇒ Object 



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# File 'lib/httpx/channel.rb', line 114

def send(request, **args)
  if @parser && !@write_buffer.full?
    parser.send(request, **args)
  else
    @pending << [request, args]
  end
end

#to_io ⇒ Object 



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# File 'lib/httpx/channel.rb', line 95

def to_io
  case @state
  when :idle
    transition(:open)
  end
  @io.to_io
end

#upgrade_parser(protocol) ⇒ Object 



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# File 'lib/httpx/channel.rb', line 136

def upgrade_parser(protocol)
  @parser.reset if @parser
  @parser = build_parser(protocol)
end