wslay is a callback based WebSocket Client and Server library written in C, it doesn't come with a event loop or does I/O operations on its own. https://github.com/tatsuhiro-t/wslay
The following callbacks are exposed in this wrapper
wslay_callbacks = Wslay::Event::Callbacks.new
wslay_callbacks.recv_callback do |buf, len|
# when wslay wants to read data
# buf is a cptr, if your I/O gem can write to a C pointer you have to write at most len bytes into it
# and return the bytes written
# or else return a mruby String or a object which can be converted into a String via to_str
# and be up to len bytes long
# the I/O object must be in non blocking mode and raise EAGAIN/EWOULDBLOCK when there is nothing to read
end
wslay_callbacks.on_msg_recv_callback do |msg|
# when a WebSocket msg is fully recieved this callback is called
# you get a Wslay::Event::OnMsgRecvArg Struct back with the following fields
# :rsv => reserved field from WebSocket spec, there are Wslay.get_rsv1/2/3 helper methods
# :opcode => :continuation_frame, :text_frame, :binary_frame, :connection_close, :ping or
# :pong, Wslay.is_ctrl_frame? helper method is provided too
# :msg => the message revieced
# :status_code => :normal_closure, :going_away, :protocol_error, :unsupported_data, :no_status_rcvd,
# :abnormal_closure, :invalid_frame_payload_data, :policy_violation, :message_too_big, :mandatory_ext,
# :internal_server_error, :tls_handshake
# to_str => returns the message revieced
end
wslay_callbacks.send_callback |buf|
# when there is data to send, you have to return the bytes send here
# the I/O object must be in non blocking mode and raise EAGAIN/EWOULDBLOCK when sending would block
end
How to setup
client = Wslay::Event::Client.new wslay_callbacks
To queue a message for sending
client.queue_msg("hello world", #optional :opcode)
To queue a close message
client.queue_close(:status_code, #optional reason)
For a fully working example: https://github.com/Asmod4n/mruby-websockets/blob/master/mrblib/client.rb
This is using code from https://github.com/tatsuhiro-t/wslay
The MIT License
Copyright (c) 2011, 2012, 2015 Tatsuhiro Tsujikawa
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