Class: Segue::Mpv

Inherits:
Object
  • Object
show all
Defined in:
lib/segue/mpv.rb

Overview

Client for mpv's JSON IPC protocol.

mpv speaks newline delimited JSON over a unix socket. Requests carry a request_id and replies echo it back, which is what lets us ignore the asynchronous event messages mpv interleaves with responses.

Defined Under Namespace

Classes: Error

Constant Summary collapse

CONNECT_TIMEOUT = 
5
LOAD_TIMEOUT = 
5
POLL_INTERVAL = 
0.05

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(socket_path) ⇒ Mpv

Returns a new instance of Mpv.



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# File 'lib/segue/mpv.rb', line 22

def initialize(socket_path)
  @socket_path = socket_path
  @request_id = 0
end

Instance Attribute Details

#socket_path ⇒ Object (readonly)

Returns the value of attribute socket_path.



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# File 'lib/segue/mpv.rb', line 20

def socket_path
  @socket_path
end

Instance Method Details

#close ⇒ Object 



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# File 'lib/segue/mpv.rb', line 68

def close
  return unless @socket

  begin
    request(["quit"])
  rescue Error, IOError, SystemCallError
    # mpv may have gone already - nothing left to ask politely
  end
  @socket.close unless @socket.closed?
  @socket = nil
end

#command(*args) ⇒ Object

Raises:



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# File 'lib/segue/mpv.rb', line 45

def command(*args)
  reply = request(args)
  raise Error, "#{args.first}: #{reply["error"]}" unless reply["error"] == "success"

  reply["data"]
end

#connect(timeout: CONNECT_TIMEOUT) ⇒ Object

mpv creates the socket a moment after it starts, so retry until it shows up.



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# File 'lib/segue/mpv.rb', line 28

def connect(timeout: CONNECT_TIMEOUT)
  deadline = Time.now + timeout
  begin
    @socket = UNIXSocket.new(socket_path)
  rescue Errno::ENOENT, Errno::ECONNREFUSED
    raise Error, "timed out waiting for mpv socket at #{socket_path}" if Time.now > deadline

    sleep POLL_INTERVAL
    retry
  end
  self
end

#connected? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/segue/mpv.rb', line 41

def connected?
  !@socket.nil?
end

#get(property) ⇒ Object

Returns nil when mpv considers a property unavailable - time-pos and duration are both unavailable whenever nothing is loaded.



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# File 'lib/segue/mpv.rb', line 54

def get(property)
  request(["get_property", property])["data"]
end

#load(path, start: nil) ⇒ Object 



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# File 'lib/segue/mpv.rb', line 62

def load(path, start: nil)
  command("loadfile", path, "replace")
  wait_for_load
  command("seek", start, "absolute") if start&.positive?
end

#set(property, value) ⇒ Object 



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# File 'lib/segue/mpv.rb', line 58

def set(property, value)
  command("set_property", property, value)
end