Support handling events by monitoring an events folder for changes

BUILD.md

@@ -14,13 +14,13 @@ Install the needed dependencies:
 For Debian-like distros:
 
 ```
-apt install -y python3-flask python3-stem python3-pyqt5 python3-crypto python3-socks  python-nautilus tor obfs4proxy python3-pytest build-essential fakeroot python3-all python3-stdeb dh-python python3-flask-httpauth python3-distutils python3-psutil
+apt install -y python3-flask python3-stem python3-pyqt5 python3-crypto python3-socks  python-nautilus tor obfs4proxy python3-pytest build-essential fakeroot python3-all python3-stdeb dh-python python3-flask-httpauth python3-distutils python3-psutil python3-watchdog
 ```
 
 For Fedora-like distros:
 
 ```
-dnf install -y python3-flask python3-flask-httpauth python3-stem python3-qt5 python3-crypto python3-pysocks nautilus-python tor obfs4 python3-pytest rpm-build python3-psutil
+dnf install -y python3-flask python3-flask-httpauth python3-stem python3-qt5 python3-crypto python3-pysocks nautilus-python tor obfs4 python3-pytest rpm-build python3-psutil python3-watchdog
 ```
 
 After that you can try both the CLI and the GUI version of OnionShare:

install/requirements.txt

@@ -21,3 +21,4 @@ requests==2.22.0
 stem==1.7.1
 urllib3==1.25.3
 Werkzeug==0.15.6
+watchdog==0.9.0

onionshare_gui/__init__.py

@@ -23,9 +23,11 @@ import sys
 import platform
 import argparse
 import signal
-import psutil
 from PyQt5 import QtCore, QtWidgets
 
+if platform.system() == "Linux":
+    import psutil
+
 from onionshare.common import Common
 
 from .gui_common import GuiCommon
@@ -122,28 +124,30 @@ def main():
             sys.exit()
 
     # Is there another onionshare-gui running?
-    existing_pid = None
+    if common.platform == "Linux":
-    for proc in psutil.process_iter(attrs=["pid", "name", "cmdline"]):
+        existing_pid = None
-        if proc.info["pid"] == os.getpid():
+        for proc in psutil.process_iter(attrs=["pid", "name", "cmdline"]):
-            continue
+            if proc.info["pid"] == os.getpid():
+                continue
 
-        if proc.info["name"] == "onionshare-gui":
+            if proc.info["name"] == "onionshare-gui":
-            existing_pid = proc.info["pid"]
+                existing_pid = proc.info["pid"]
-            break
+                break
-        else:
+            else:
-            # Dev mode onionshare?
+                # Dev mode onionshare?
-            if proc.info["cmdline"] and len(proc.info["cmdline"]) >= 2:
+                if proc.info["cmdline"] and len(proc.info["cmdline"]) >= 2:
-                if (
+                    if (
-                    os.path.basename(proc.info["cmdline"][0]).lower() == "python"
+                        os.path.basename(proc.info["cmdline"][0]).lower() == "python"
-                    and os.path.basename(proc.info["cmdline"][1]) == "onionshare-gui"
+                        and os.path.basename(proc.info["cmdline"][1])
-                ):
+                        == "onionshare-gui"
-                    existing_pid = proc.info["pid"]
+                    ):
-                    break
+                        existing_pid = proc.info["pid"]
+                        break
 
-    if existing_pid:
+        if existing_pid:
-        print(f"Opening tab in existing OnionShare window (pid {proc.info['pid']})")
+            print(f"Opening tab in existing OnionShare window (pid {proc.info['pid']})")
-        # TODO: open tab
+            # TODO: open tab
-        return
+            return
 
     # Attach the GUI common parts to the common object
     common.gui = GuiCommon(common, qtapp, local_only)

onionshare_gui/event_handler.py

@@ -0,0 +1,89 @@
+# -*- 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 json
+import os
+from watchdog.observers import Observer
+from watchdog.events import FileSystemEventHandler, FileModifiedEvent
+from PyQt5 import QtCore
+
+
+class EventHandler(FileSystemEventHandler, QtCore.QObject):
+    """
+    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(EventHandler, self).__init__()
+        self.common = common
+
+    def on_modified(self, event):
+        if (
+            type(event) == FileModifiedEvent
+            and event.src_path == self.common.gui.events_filename
+        ):
+            # Read all the lines in the events, then delete it
+            with open(self.common.gui.events_filename, "r") as f:
+                lines = f.readlines()
+            os.remove(self.common.gui.events_filename)
+
+            self.common.log(
+                "EventHandler", "on_modified", f"processing {len(lines)} lines"
+            )
+            for line in lines:
+                try:
+                    obj = json.loads(line)
+                    if "type" not in obj:
+                        self.common.log(
+                            "EventHandler",
+                            "on_modified",
+                            f"event does not have a type: {obj}",
+                        )
+                        continue
+                except json.decoder.JSONDecodeError:
+                    self.common.log(
+                        "EventHandler", "on_modified", f"ignoring invalid line: {line}"
+                    )
+                    continue
+
+                if obj["type"] == "new_tab":
+                    self.common.log("EventHandler", "on_modified", "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",
+                            "on_modified",
+                            f"invalid new_share_tab event: {obj}",
+                        )
+
+                else:
+                    self.common.log(
+                        "EventHandler", "on_modified", f"invalid event type: {obj}"
+                    )
+

onionshare_gui/gui_common.py

@@ -17,6 +17,8 @@ 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 os
+
 from onionshare import strings
 from onionshare.onion import Onion
 
@@ -44,6 +46,12 @@ class GuiCommon:
         # Start the Onion
         self.onion = Onion(common)
 
+        # Directory to watch for events
+        self.events_dir = os.path.join(self.common.build_data_dir(), "events")
+        if not os.path.exists(self.events_dir):
+            os.makedirs(self.events_dir, 0o700, True)
+        self.events_filename = os.path.join(self.events_dir, "events")
+
         self.css = {
             # OnionShareGui styles
             "tab_widget_new_tab_button": """

onionshare_gui/main_window.py

@@ -119,6 +119,7 @@ class MainWindow(QtWidgets.QMainWindow):
 
         # Tabs
         self.tabs = TabWidget(self.common, self.system_tray, self.status_bar)
+        self.tabs.bring_to_front.connect(self.bring_to_front)
 
         # If we have saved persistent tabs, try opening those
         if len(self.common.settings.get("persistent_tabs")) > 0:
@@ -281,6 +282,11 @@ class MainWindow(QtWidgets.QMainWindow):
                 self.update_thread.update_available.connect(update_available)
                 self.update_thread.start()
 
+    def bring_to_front(self):
+        self.common.log("MainWindow", "bring_to_front")
+        self.raise_()
+        self.activateWindow()
+
     def closeEvent(self, e):
         self.common.log("MainWindow", "closeEvent")
 

onionshare_gui/tab_widget.py

@@ -18,11 +18,13 @@ You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 """
 from PyQt5 import QtCore, QtWidgets, QtGui
+from watchdog.observers import Observer
 
 from onionshare import strings
 from onionshare.mode_settings import ModeSettings
 
 from .tab import Tab
+from .event_handler import EventHandler
 
 
 class TabWidget(QtWidgets.QTabWidget):
@@ -30,6 +32,8 @@ class TabWidget(QtWidgets.QTabWidget):
     A custom tab widget, that has a "+" button for adding new tabs
     """
 
+    bring_to_front = QtCore.pyqtSignal()
+
     def __init__(self, common, system_tray, status_bar):
         super(TabWidget, self).__init__()
         self.common = common
@@ -67,6 +71,14 @@ class TabWidget(QtWidgets.QTabWidget):
 
         self.move_new_tab_button()
 
+        # Watch the events file for changes
+        self.event_handler = EventHandler(common)
+        self.event_handler.new_tab.connect(self.add_tab)
+        self.event_handler.new_share_tab.connect(self.new_share_tab)
+        self.observer = Observer()
+        self.observer.schedule(self.event_handler, self.common.gui.events_dir)
+        self.observer.start()
+
     def move_new_tab_button(self):
         # Find the width of all tabs
         tabs_width = sum(
@@ -95,6 +107,12 @@ class TabWidget(QtWidgets.QTabWidget):
         mode_settings = ModeSettings(self.common, id=mode_settings_id)
         self.add_tab(mode_settings)
 
+    def new_share_tab(self, filenames):
+        mode_settings = ModeSettings(self.common)
+        mode_settings.set("persistent", "mode", "share")
+        mode_settings.set("share", "filenames", filenames)
+        self.add_tab(mode_settings)
+
     def add_tab(self, mode_settings=None):
         tab = Tab(self.common, self.current_tab_id, self.system_tray, self.status_bar)
         tab.change_title.connect(self.change_title)
@@ -111,6 +129,9 @@ class TabWidget(QtWidgets.QTabWidget):
         # If it's persistent, set the persistent image in the tab
         self.change_persistent(tab.tab_id, tab.settings.get("persistent", "enabled"))
 
+        # Bring the window to front, in case this is being added by an event
+        self.bring_to_front.emit()
+
     def change_title(self, tab_id, title):
         index = self.indexOf(self.tabs[tab_id])
         self.setTabText(index, title)