omxplayer-controller-node/lib/omxp_dbus.js

Raspberry Pi omxplayer controll using dbus-native

var dbus = require("dbus-native"),
  fs = require("fs"),
  events = require("events"),
  eventEmitter = new events.EventEmitter();
var omx_methods = require("./omx_methods");
var omxp_spawn = require("./omxp_spawn");
var prev_status = "";
var bus;

var tickInterval = 5000;
var tick;

function openPlayer(path, options) {
  const player = omxp_spawn.player(path, options);
  player.once("close", function (silent) {
    if (typeof tick !== "undefined") clearInterval(tick);
    if (silent) {
      eventEmitter.emit("error", path);
    } else {
      eventEmitter.emit("finish", path);
    }
  });
  var conn_interval = setInterval(function () {
    if (fs.existsSync("/tmp/omxplayerdbus." + process.env.USER)) {
      bus = dbus.sessionBus({
        busAddress: fs
          .readFileSync("/tmp/omxplayerdbus." + process.env.USER, "ascii")
          .trim(),
      });
      setTimeout(getPlayerStatus, 500);
      tick = setInterval(getPlayerStatus, tickInterval);
      clearInterval(conn_interval);
    }
  }, 500);
  // return { path, pid: player.pid };
  return player;
}

function quitPlayer(signal) {
  signal.stdin.end();
}

function playersRunning(cb) {
  omxp_spawn.omxp_running(function (count) {
    cb(null, count);
  });
}

function setTickInterval(tick_int) {
  tickInterval = tick_int;
}

function propertyRead(prop, cb) {
  if (
    typeof omx_methods.properties[prop] !== "undefined" &&
    omx_methods.properties[prop].read
  ) {
    if (typeof bus !== "undefined") {
      bus.invoke(
        {
          path: "/org/mpris/MediaPlayer20",
          interface: "org.freedesktop.DBus.Properties",
          member: prop,
          destination: "org.mpris.MediaPlayer20.omxplayer",
        },
        function (err, resp) {
          return cb(err, resp);
        }
      );
    } else {
      return cb(new Error("Not ready yet"));
    }
  } else {
    return cb(new Error("Invalid property"));
  }
}

function propertyWrite(prop, val, cb) {
  if (typeof bus !== "undefined") {
    if (
      typeof omx_methods.properties[prop] !== "undefined" &&
      omx_methods.properties[prop].read
    ) {
      bus.invoke(
        {
          path: "/org/mpris/MediaPlayer20",
          interface: "org.mpris.MediaPlayer20.Player",
          member: prop,
          destination: "org.mpris.MediaPlayer20.omxplayer",
          signature: omx_methods.properties[prop].signature,
          body: val,
        },
        function (err) {
          return cb(err);
        }
      );
    } else {
      return cb(new Error("Invalid property"));
    }
  } else {
    return cb(new Error("Not ready yet"));
  }
}

function method(action, val, cb) {
  cb = typeof val === "function" ? val : cb;
  if (typeof bus !== "undefined") {
    if (typeof omx_methods.methods[action] !== "undefined") {
      bus.invoke(
        {
          path: "/org/mpris/MediaPlayer20",
          interface: "org.mpris.MediaPlayer20.Player",
          destination: "org.mpris.MediaPlayer20.omxplayer",
          member: action,
          signature: omx_methods.methods[action].write
            ? omx_methods.methods[action].signature
            : null,
          body: omx_methods.methods[action].write ? val : null,
        },
        function (err, val) {
          cb(err, val);
        }
      );
    } else {
      return cb(new Error("Invalid method"));
    }
  } else {
    return cb(new Error("Not ready yet"));
  }
}

function getPlayerStatus() {
  propertyRead("PlaybackStatus", function (err0, status) {
    if (err0)
      return eventEmitter.emit("changeStatus", {
        status: "Stopped",
      });
    propertyRead("Duration", function (err1, duration) {
      if (err1)
        return eventEmitter.emit("changeStatus", {
          status: "Stopped",
        });
      propertyRead("Position", function (err2, pos) {
        if (err2)
          return eventEmitter.emit("changeStatus", {
            status: "Stopped",
          });
        propertyRead("Volume", function (err3, vol) {
          if (err3)
            return eventEmitter.emit("changeStatus", {
              status: "Stopped",
            });
          var new_status = {
            status: status,
            duration: duration,
            pos: pos,
            vol: vol,
          };
          if (JSON.stringify(new_status) !== JSON.stringify(prev_status)) {
            eventEmitter.emit("changeStatus", new_status);
            prev_status = new_status;
          }
        });
      });
    });
  });
}
module.exports = eventEmitter;
//================================================
//This part should be removed once able to setVolume with out it (the way every other function works).
var exec = require("child_process").exec;

function setVolume(val, cb) {
  var cmd =
    'OMXPLAYER_DBUS_ADDR="/tmp/omxplayerdbus.${USER:-root}";OMXPLAYER_DBUS_PID="/tmp/omxplayerdbus.${USER:-root}.pid";export DBUS_SESSION_BUS_ADDRESS=`cat $OMXPLAYER_DBUS_ADDR`;export DBUS_SESSION_BUS_PID=`cat $OMXPLAYER_DBUS_PID`;dbus-send --print-reply=literal --session --reply-timeout=500 --dest=org.mpris.MediaPlayer20.omxplayer /org/mpris/MediaPlayer2 org.freedesktop.DBus.Properties.Volume double:';
  exec(cmd + val, function (stderr, stdout) {
    if (stderr) return cb(new Error(stderr));
    var vol_d = parseFloat(
      stdout.substr(stdout.indexOf("double") + 7, stdout.length)
    );
    cb(null, vol_d);
  });
}
module.exports.setVolume = setVolume;
//================================================
module.exports.openPlayer = openPlayer;
module.exports.quitPlayer = quitPlayer;
module.exports.propertyRead = propertyRead;
module.exports.propertyWrite = propertyWrite;
module.exports.method = method;
module.exports.setTickInterval = setTickInterval;
module.exports.playersRunning = playersRunning;