Class: Plushie::Connection

Inherits:
Object
  • Object
show all
Defined in:
lib/plushie/connection.rb

Overview

Low-level protocol client for the plushie renderer.

Manages a bidirectional pipe to the renderer binary, handles wire framing, and provides thread-safe message sending. Decoded messages are pushed to a Thread::Queue or dispatched via a callback proc.

This layer is usable standalone for scripting and REPL exploration without the full Elm architecture:

conn = Plushie::Connection.spawn(format: :json) # hello is available after spawn puts conn.hello[:version] conn.send_encoded(Protocol::Encode.encode_snapshot(tree, :json)) conn.close

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#format ⇒ :msgpack, :json (readonly)

Returns wire format.

Returns:

  • (:msgpack, :json) —

    wire format



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# File 'lib/plushie/connection.rb', line 23

def format
  @format
end

#hello ⇒ Hash? (readonly)

Returns hello handshake response from renderer.

Returns:

  • (Hash, nil) —

    hello handshake response from renderer



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# File 'lib/plushie/connection.rb', line 26

def hello
  @hello
end

Class Method Details

.attach(stdin:, stdout:, format: :msgpack, settings: {}, queue: nil, on_message: nil) ⇒ Connection

Attach to existing IO streams (for :stdio transport).

Parameters:

  • stdin (IO) —

    writable stream to renderer

  • stdout (IO) —

    readable stream from renderer

  • format (:msgpack, :json) (defaults to: :msgpack) —

    wire format

  • settings (Hash) (defaults to: {}) —

    initial settings to send

  • queue (Thread::Queue, nil) (defaults to: nil)
  • on_message (Proc, nil) (defaults to: nil)

Returns:



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# File 'lib/plushie/connection.rb', line 57

def self.attach(stdin:, stdout:, format: :msgpack, settings: {},
  queue: nil, on_message: nil)
  conn = new(format: format, queue: queue, on_message: on_message)
  conn.instance_variable_set(:@stdin, stdin)
  conn.instance_variable_set(:@stdout, stdout)
  stdin.binmode
  stdout.binmode
  conn.send(:perform_handshake, settings)
  conn.send(:start_reader)
  conn
end

.iostream(adapter:, format: :msgpack, settings: {}, queue: nil, on_message: nil) ⇒ Connection

Create a connection backed by an iostream adapter.

The adapter mediates between the Connection and an external I/O source (SSH channel, TCP socket, WebSocket, etc.). Instead of reading/writing pipes, the connection exchanges data with the adapter via method calls.

The adapter must respond to:

  • +on_bridge(connection)+ -- called during init, adapter stores connection ref
  • +send_data(data)+ -- called by Connection to write encoded bytes

The adapter calls back:

  • +connection.receive_data(data)+ -- when data arrives from the transport
  • +connection.transport_closed(reason)+ -- when the transport closes

Parameters:

  • adapter (#on_bridge, #send_data) —

    iostream adapter object

  • format (:msgpack, :json) (defaults to: :msgpack) —

    wire format

  • settings (Hash) (defaults to: {}) —

    initial settings to send

  • queue (Thread::Queue, nil) (defaults to: nil)
  • on_message (Proc, nil) (defaults to: nil)

Returns:



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# File 'lib/plushie/connection.rb', line 90

def self.iostream(adapter:, format: :msgpack, settings: {},
  queue: nil, on_message: nil)
  conn = new(format: format, queue: queue, on_message: on_message)
  conn.send(:setup_iostream, adapter, settings)
  conn
end

.spawn(format: :msgpack, binary: nil, mode: nil, max_sessions: nil, log_level: nil, settings: {}, queue: nil, on_message: nil) ⇒ Connection

Spawn a renderer process and perform the hello handshake.

Parameters:

  • format (:msgpack, :json) (defaults to: :msgpack) —

    wire format

  • binary (String, nil) (defaults to: nil) —

    path to renderer binary (nil = auto-resolve)

  • mode (:windowed, :headless, :mock, nil) (defaults to: nil) —

    execution mode

  • max_sessions (Integer, nil) (defaults to: nil) —

    max concurrent sessions

  • log_level (Symbol, nil) (defaults to: nil) —

    renderer log level

  • settings (Hash) (defaults to: {}) —

    initial settings to send

  • queue (Thread::Queue, nil) (defaults to: nil) —

    queue to push decoded messages to

  • on_message (Proc, nil) (defaults to: nil) —

    callback for decoded messages (alternative to queue)

Returns:



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# File 'lib/plushie/connection.rb', line 39

def self.spawn(format: :msgpack, binary: nil, mode: nil, max_sessions: nil,
  log_level: nil, settings: {}, queue: nil, on_message: nil)
  conn = new(format: format, queue: queue, on_message: on_message)
  conn.send(:spawn_process, binary, mode, max_sessions, log_level)
  conn.send(:perform_handshake, settings)
  conn.send(:start_reader)
  conn
end

Instance Method Details

#close ⇒ Object

Close the connection and clean up resources.



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# File 'lib/plushie/connection.rb', line 164

def close
  return if @closed
  @closed = true
  @reader_thread&.kill
  if @iostream_adapter
    @iostream_adapter.stop if @iostream_adapter.respond_to?(:stop)
  else
    begin
      @stdin&.close
    rescue
      nil
    end
    begin
      @stdout&.close
    rescue
      nil
    end
    begin
      @process_thread&.value
    rescue
      nil
    end
  end
end

#closed? ⇒ Boolean

Returns true if the connection is closed.

Returns:

  • (Boolean) —

    true if the connection is closed



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# File 'lib/plushie/connection.rb', line 190

def closed?
  @closed
end

#receive_data(data) ⇒ Object

Called by the iostream adapter when data arrives from the transport. The adapter is responsible for framing -- each call should deliver one complete protocol message.

Parameters:

  • data (String) —

    a complete protocol message (decoded from framing)



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# File 'lib/plushie/connection.rb', line 125

def receive_data(data)
  return if @closed

  msg = Protocol::Decode.decode(data, @format)
  decoded = Protocol::Decode.dispatch_message(msg)

  if !@hello && decoded.is_a?(Hash) && decoded[:type] == :hello
    @hello = decoded
    @handshake_queue&.push(decoded)
  elsif decoded
    dispatch_message(decoded)
  end
end

#send_encoded(data) ⇒ Object

Send pre-encoded wire bytes to the renderer. Thread-safe.

Parameters:

  • data (String) —

    encoded message bytes



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# File 'lib/plushie/connection.rb', line 100

def send_encoded(data)
  @write_mutex.synchronize do
    if @iostream_adapter
      @iostream_adapter.send_data(data)
    else
      case @format
      when :msgpack
        @stdin.write([data.bytesize].pack("N"))
        @stdin.write(data)
      when :json
        @stdin.write(data)
      end
      @stdin.flush
    end
  end
rescue IOError, Errno::EPIPE => e
  @closed = true
  dispatch_message({type: :connection_error, error: e})
end

#send_message(msg) ⇒ Object

Encode a hash and send it. Injects session field if missing.

Parameters:

  • msg (Hash) —

    message to encode and send



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# File 'lib/plushie/connection.rb', line 151

def send_message(msg)
  send_encoded(Protocol::Encode.encode(msg, @format))
end

#send_message_for_session(msg, session_id) ⇒ Object

Send a message with a specific session ID injected.

Parameters:

  • msg (Hash) —

    message hash

  • session_id (String) —

    session identifier



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# File 'lib/plushie/connection.rb', line 159

def send_message_for_session(msg, session_id)
  send_message(msg.merge(session: session_id))
end

#transport_closed(reason) ⇒ Object

Called by the iostream adapter when the transport closes.

Parameters:

  • reason (Symbol, String) —

    reason for closure



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# File 'lib/plushie/connection.rb', line 142

def transport_closed(reason)
  return if @closed
  @closed = true
  dispatch_message({type: :connection_closed, reason: reason})
end