fm_output.py

from output import Output
import subprocess
from configuration import config
from subprocess import call
import os


class FmOutput(Output):

    __frequency = None
    __rds_ctl = None

    def __init__(self):
        super().__init__()
        self.__load_settings()

    def __load_settings(self):
        self.__frequency = config.get_settings()["PIRATERADIO"]["frequency"]
        self.__rds_ctl = config.get_rds_ctl()
        try:
            os.remove(self.__rds_ctl)
        except FileNotFoundError:
            pass
        try:
            os.mkfifo(self.__rds_ctl)
        except FileExistsError:
            pass

    def run(self):
        print("broadcasting on FM", self.__frequency)
        self.stream = subprocess.Popen(["sudo", "pi_fm_adv", "--freq", self.__frequency,
                                        "--ctl", self.__rds_ctl, "--audio", "-"],
                                       stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        self.input_stream = self.stream.stdin
        self.ready.set()

    def stop(self):
        call(["sudo", "pkill", "-P", str(self.stream.pid)])
        self.stream.wait()

    def reload(self):
        self.ready.clear()
        self.stop()
        self.__load_settings()
        self.run()

    def check_reload(self):
        if self.__frequency != config.get_settings()["PIRATERADIO"]["frequency"]:
            self.reload()