In-Band Bytestreams (JEP-0047) implementation
Don't use directly, use IBBInitiator and IBBTarget
In-Band Bytestreams should only be used when transferring very small amounts of binary data, because it is slow and increases server load drastically.
Note that the constructor takes a lot of arguments. In-Band Bytestreams do not specify a way to initiate the stream, this should be done via Stream Initiation.
Create a new bytestream
Will register a <message/> callback to intercept data of this stream. This data will be buffered, you can retrieve it with receive
# File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 30 def initialize(stream, session_id, my_jid, peer_jid) @stream = stream @session_id = session_id @my_jid = (my_jid.kind_of?(String) ? JID.new(my_jid) : my_jid) @peer_jid = (peer_jid.kind_of?(String) ? JID.new(peer_jid) : peer_jid) @active = false @seq_send = 0 @seq_recv = 0 @queue = [] @queue_lock = Mutex.new @pending = Semaphore.new @sendbuf = '' @sendbuf_lock = Mutex.new @block_size = 4096 # Recommended by JEP0047 end
# File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 48 def active? @active end
Close the stream
Waits for acknowledge from peer, may throw ServerError
# File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 128 def close if active? flush deactivate iq = Iq.new(:set, @peer_jid) close = iq.add REXML::Element.new('close') close.add_namespace IBB::NS_IBB close.attributes['sid'] = @session_id @stream.send_with_id(iq) end end
Empty the send-buffer by sending remaining data
# File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 72 def flush @sendbuf_lock.synchronize { while @sendbuf.size > 0 send_data(@sendbuf[0..@block_size-1]) @sendbuf = @sendbuf[@block_size..-1].to_s end } end
Receive data
Will wait until the Message with the next sequence number is in the stanza queue.
# File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 86 def read if active? res = nil while res.nil? @queue_lock.synchronize { @queue.each { |item| # Find next data if item.type == :data and item.seq == @seq_recv.to_s res = item break # No data? Find close elsif item.type == :close and res.nil? res = item end } @queue.delete_if { |item| item == res } } # No data? Wait for next to arrive... @pending.wait unless res end if res.type == :data @seq_recv += 1 @seq_recv = 0 if @seq_recv > 65535 res.data elsif res.type == :close deactivate nil # Closed end else nil end end
Send data
Data is buffered to match block_size in each packet. If you need the data to be sent immediately, use flush afterwards.
# File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 59 def write(buf) @sendbuf_lock.synchronize { @sendbuf += buf while @sendbuf.size >= @block_size send_data(@sendbuf[0..@block_size-1]) @sendbuf = @sendbuf[@block_size..-1].to_s end } end