onionshare/onionshare_gui/threads.py

# -*- coding: utf-8 -*-
"""
OnionShare | https://onionshare.org/

Copyright (C) 2014-2018 Micah Lee <micah@micahflee.com>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
"""
import time
import json
import os
from PyQt5 import QtCore

from onionshare import strings
from onionshare.onion import (
    TorTooOld,
    TorErrorInvalidSetting,
    TorErrorAutomatic,
    TorErrorSocketPort,
    TorErrorSocketFile,
    TorErrorMissingPassword,
    TorErrorUnreadableCookieFile,
    TorErrorAuthError,
    TorErrorProtocolError,
    BundledTorTimeout,
)


class OnionThread(QtCore.QThread):
    """
    Starts the onion service, and waits for it to finish
    """

    success = QtCore.pyqtSignal()
    success_early = QtCore.pyqtSignal()
    error = QtCore.pyqtSignal(str)

    def __init__(self, mode):
        super(OnionThread, self).__init__()
        self.mode = mode
        self.mode.common.log("OnionThread", "__init__")

        # allow this thread to be terminated
        self.setTerminationEnabled()

    def run(self):
        self.mode.common.log("OnionThread", "run")

        # Make a new static URL path for each new share
        self.mode.web.generate_static_url_path()

        # Choose port and password early, because we need them to exist in advance for scheduled shares
        if not self.mode.app.port:
            self.mode.app.choose_port()
        if not self.mode.settings.get("general", "public"):
            if not self.mode.web.password:
                self.mode.web.generate_password(
                    self.mode.settings.get("onion", "password")
                )

        try:
            if self.mode.obtain_onion_early:
                self.mode.app.start_onion_service(
                    self.mode.settings, await_publication=False
                )
                # wait for modules in thread to load, preventing a thread-related cx_Freeze crash
                time.sleep(0.2)
                self.success_early.emit()
                # Unregister the onion so we can use it in the next OnionThread
                self.mode.app.stop_onion_service(self.mode.settings)
            else:
                self.mode.app.start_onion_service(
                    self.mode.settings, await_publication=True
                )
                # wait for modules in thread to load, preventing a thread-related cx_Freeze crash
                time.sleep(0.2)
                # start onionshare http service in new thread
                self.mode.web_thread = WebThread(self.mode)
                self.mode.web_thread.start()
                self.success.emit()

        except (
            TorTooOld,
            TorErrorInvalidSetting,
            TorErrorAutomatic,
            TorErrorSocketPort,
            TorErrorSocketFile,
            TorErrorMissingPassword,
            TorErrorUnreadableCookieFile,
            TorErrorAuthError,
            TorErrorProtocolError,
            BundledTorTimeout,
            OSError,
        ) as e:
            self.error.emit(e.args[0])
            return


class WebThread(QtCore.QThread):
    """
    Starts the web service
    """

    success = QtCore.pyqtSignal()
    error = QtCore.pyqtSignal(str)

    def __init__(self, mode):
        super(WebThread, self).__init__()
        self.mode = mode
        self.mode.common.log("WebThread", "__init__")

    def run(self):
        self.mode.common.log("WebThread", "run")
        self.mode.web.start(self.mode.app.port)
        self.success.emit()


class AutoStartTimer(QtCore.QThread):
    """
    Waits for a prescribed time before allowing a share to start
    """

    success = QtCore.pyqtSignal()
    error = QtCore.pyqtSignal(str)

    def __init__(self, mode, canceled=False):
        super(AutoStartTimer, self).__init__()
        self.mode = mode
        self.canceled = canceled
        self.mode.common.log("AutoStartTimer", "__init__")

        # allow this thread to be terminated
        self.setTerminationEnabled()

    def run(self):
        now = QtCore.QDateTime.currentDateTime()
        autostart_timer_datetime_delta = now.secsTo(
            self.mode.server_status.autostart_timer_datetime
        )
        try:
            # Sleep until scheduled time
            while autostart_timer_datetime_delta > 0 and self.canceled == False:
                time.sleep(0.1)
                now = QtCore.QDateTime.currentDateTime()
                autostart_timer_datetime_delta = now.secsTo(
                    self.mode.server_status.autostart_timer_datetime
                )
            # Timer has now finished
            if self.canceled == False:
                self.mode.server_status.server_button.setText(
                    strings._("gui_please_wait")
                )
                self.mode.server_status_label.setText(
                    strings._("gui_status_indicator_share_working")
                )
                self.success.emit()
        except ValueError as e:
            self.error.emit(e.args[0])
            return


class EventHandlerThread(QtCore.QThread):
    """
    To trigger an event, write a JSON line to the events file. When that file changes, 
    each line will be handled as an event. Valid events are:
    {"type": "new_tab"}
    {"type": "new_share_tab", "filenames": ["file1", "file2"]}
    """

    new_tab = QtCore.pyqtSignal()
    new_share_tab = QtCore.pyqtSignal(list)

    def __init__(self, common):
        super(EventHandlerThread, self).__init__()
        self.common = common
        self.common.log("EventHandlerThread", "__init__")
        self.should_quit = False

    def run(self):
        self.common.log("EventHandlerThread", "run")

        mtime = 0
        while True:
            if os.path.exists(self.common.gui.events_filename):
                # Events file exists
                if os.stat(self.common.gui.events_filename).st_mtime != mtime:
                    # Events file has been modified, load events
                    try:
                        with open(self.common.gui.events_filename, "r") as f:
                            lines = f.readlines()
                        os.remove(self.common.gui.events_filename)

                        self.common.log(
                            "EventHandler", "run", f"processing {len(lines)} lines"
                        )
                        for line in lines:
                            try:
                                obj = json.loads(line)
                                if "type" not in obj:
                                    self.common.log(
                                        "EventHandler",
                                        "run",
                                        f"event does not have a type: {obj}",
                                    )
                                    continue
                            except json.decoder.JSONDecodeError:
                                self.common.log(
                                    "EventHandler",
                                    "run",
                                    f"ignoring invalid line: {line}",
                                )
                                continue

                            if obj["type"] == "new_tab":
                                self.common.log("EventHandler", "run", "new_tab event")
                                self.new_tab.emit()

                            elif obj["type"] == "new_share_tab":
                                if (
                                    "filenames" in obj
                                    and type(obj["filenames"]) is list
                                ):
                                    self.new_share_tab.emit(obj["filenames"])
                                else:
                                    self.common.log(
                                        "EventHandler",
                                        "run",
                                        f"invalid new_share_tab event: {obj}",
                                    )

                            else:
                                self.common.log(
                                    "EventHandler", "run", f"invalid event type: {obj}"
                                )

                    except:
                        pass

            if self.should_quit:
                break
            time.sleep(0.2)