Class Jabber::Bytestreams::IBB
In: lib/xmpp4r/bytestreams/helper/ibb/base.rb
Parent: Object

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.

Methods

active?   close   flush   new   read   write  

Constants

NS_IBB = 'http://jabber.org/protocol/ibb'

Public Class methods

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

[Source]

    # File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 30
30:       def initialize(stream, session_id, my_jid, peer_jid)
31:         @stream = stream
32:         @session_id = session_id
33:         @my_jid = (my_jid.kind_of?(String) ? JID.new(my_jid) : my_jid)
34:         @peer_jid = (peer_jid.kind_of?(String) ? JID.new(peer_jid) : peer_jid)
35: 
36:         @active = false
37:         @seq_send = 0
38:         @seq_recv = 0
39:         @queue = []
40:         @queue_lock = Mutex.new
41:         @pending = Semaphore.new
42:         @sendbuf = ''
43:         @sendbuf_lock = Mutex.new
44: 
45:         @block_size = 4096  # Recommended by JEP0047
46:       end

Public Instance methods

[Source]

    # File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 48
48:       def active?
49:         @active
50:       end

Close the stream

Waits for acknowledge from peer, may throw ServerError

[Source]

     # File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 128
128:       def close
129:         if active?
130:           flush
131:           deactivate
132: 
133:           iq = Iq.new(:set, @peer_jid)
134:           close = iq.add REXML::Element.new('close')
135:           close.add_namespace IBB::NS_IBB
136:           close.attributes['sid'] = @session_id
137: 
138:           @stream.send_with_id(iq)
139:         end
140:       end

Empty the send-buffer by sending remaining data

[Source]

    # File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 72
72:       def flush
73:         @sendbuf_lock.synchronize {
74:           while @sendbuf.size > 0
75:             send_data(@sendbuf[0..@block_size-1])
76:             @sendbuf = @sendbuf[@block_size..-1].to_s
77:           end
78:         }
79:       end

Receive data

Will wait until the Message with the next sequence number is in the stanza queue.

[Source]

     # File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 86
 86:       def read
 87:         if active?
 88:           res = nil
 89: 
 90:           while res.nil?
 91:             @queue_lock.synchronize {
 92:               @queue.each { |item|
 93:                 # Find next data
 94:                 if item.type == :data and item.seq == @seq_recv.to_s
 95:                   res = item
 96:                   break
 97:                 # No data? Find close
 98:                 elsif item.type == :close and res.nil?
 99:                   res = item
100:                 end
101:               }
102: 
103:               @queue.delete_if { |item| item == res }
104:             }
105: 
106:             # No data? Wait for next to arrive...
107:             @pending.wait unless res
108:           end
109: 
110:           if res.type == :data
111:             @seq_recv += 1
112:             @seq_recv = 0 if @seq_recv > 65535
113:             res.data
114:           elsif res.type == :close
115:             deactivate
116:             nil # Closed
117:           end
118:         else
119:           nil
120:         end
121:       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.

buf:[String]

[Source]

    # File lib/xmpp4r/bytestreams/helper/ibb/base.rb, line 59
59:       def write(buf)
60:         @sendbuf_lock.synchronize {
61:           @sendbuf += buf
62: 
63:           while @sendbuf.size >= @block_size
64:             send_data(@sendbuf[0..@block_size-1])
65:             @sendbuf = @sendbuf[@block_size..-1].to_s
66:           end
67:         }
68:       end

[Validate]