Catch installation errors and display them.

Fixes #193

dangerzone/gui/main_window.py

@@ -1,7 +1,6 @@
 import logging
 import os
 import platform
-import subprocess
 import tempfile
 import typing
 from multiprocessing.pool import ThreadPool
@@ -20,15 +19,19 @@
  from PySide6.QtWidgets import QTextEdit
  except ImportError:
  from PySide2 import QtCore, QtGui, QtSvg, QtWidgets
- from PySide2.QtWidgets import QAction, QTextEdit
  from PySide2.QtCore import Qt
+ from PySide2.QtWidgets import QAction, QTextEdit
 
 from .. import errors
 from ..document import SAFE_EXTENSION, Document
-from ..isolation_provider.container import Container, NoContainerTechException
+from ..isolation_provider.container import (
+ Container,
+ NoContainerTechException,
+ NotAvailableContainerTechException,
+)
 from ..isolation_provider.dummy import Dummy
 from ..isolation_provider.qubes import Qubes, is_qubes_native_conversion
-from ..util import get_resource_path, get_subprocess_startupinfo, get_version
+from ..util import format_exception, get_resource_path, get_version
 from .logic import Alert, CollapsibleBox, DangerzoneGui, UpdateDialog
 from .updater import UpdateReport
 
@@ -388,15 +391,24 @@ def closeEvent(self, e: QtGui.QCloseEvent) -> None:
 
 
 class InstallContainerThread(QtCore.QThread):
- finished = QtCore.Signal()
+ finished = QtCore.Signal(str)
 
  def __init__(self, dangerzone: DangerzoneGui) -> None:
  super(InstallContainerThread, self).__init__()
  self.dangerzone = dangerzone
 
  def run(self) -> None:
- self.dangerzone.isolation_provider.install()
- self.finished.emit()
+ error = None
+ try:
+ installed = self.dangerzone.isolation_provider.install()
+ except Exception as e:
+ log.error("Container installation problem")
+ error = format_exception(e)
+ else:
+ if not installed:
+ error = "The image cannot be found. This can be caused by a faulty container image."
+ finally:
+ self.finished.emit(error)
 
 
 class WaitingWidget(QtWidgets.QWidget):
@@ -423,9 +435,10 @@ def __init__(self) -> None:
  # Enable copying
  self.setTextInteractionFlags(Qt.TextSelectableByMouse)
 
- def set_content(self, error: str) -> None:
- self.setPlainText(error)
- self.setVisible(True)
+ def set_content(self, error: Optional[str] = None) -> None:
+ if error:
+ self.setPlainText(error)
+ self.setVisible(True)
 
 
 class WaitingWidgetContainer(WaitingWidget):
@@ -438,7 +451,6 @@ class WaitingWidgetContainer(WaitingWidget):
  #
  # Linux states
  # - "install_container"
- finished = QtCore.Signal()
 
  def __init__(self, dangerzone: DangerzoneGui) -> None:
  super(WaitingWidgetContainer, self).__init__()
@@ -480,77 +492,82 @@ def check_state(self) -> None:
  error: Optional[str] = None
 
  try:
- if isinstance( # Sanity check
- self.dangerzone.isolation_provider, Container
- ):
- container_runtime = self.dangerzone.isolation_provider.get_runtime()
- runtime_name = self.dangerzone.isolation_provider.get_runtime_name()
+ self.dangerzone.isolation_provider.is_runtime_available()
  except NoContainerTechException as e:
  log.error(str(e))
  state = "not_installed"
-
+ except NotAvailableContainerTechException as e:
+ log.error(str(e))
+ state = "not_running"
+ error = e.error
+ except Exception as e:
+ log.error(str(e))
+ state = "not_running"
+ error = format_exception(e)
  else:
- # Can we run `docker/podman image ls` without an error
- with subprocess.Popen(
- [container_runtime, "image", "ls"],
- stdout=subprocess.DEVNULL,
- stderr=subprocess.PIPE,
- startupinfo=get_subprocess_startupinfo(),
- ) as p:
- _, stderr = p.communicate()
- if p.returncode != 0:
- log.error(f"{runtime_name} is not running")
- state = "not_running"
- error = stderr.decode()
- else:
- # Always try installing the container
- state = "install_container"
+ state = "install_container"
 
  # Update the state
  self.state_change(state, error)
 
+ def show_error(self, msg: str, details: Optional[str] = None) -> None:
+ self.label.setText(msg)
+ show_traceback = details is not None
+ if show_traceback:
+ self.traceback.set_content(details)
+ self.traceback.setVisible(show_traceback)
+ self.buttons.show()
+
+ def show_message(self, msg: str) -> None:
+ self.label.setText(msg)
+ self.traceback.setVisible(False)
+ self.buttons.hide()
+
+ def installation_finished(self, error: Optional[str] = None) -> None:
+ if error:
+ msg = (
+ "During installation of the dangerzone image, <br>"
+ "the following error occured:"
+ )
+ self.show_error(msg, error)
+ else:
+ self.finished.emit()
+
  def state_change(self, state: str, error: Optional[str] = None) -> None:
  if state == "not_installed":
  if platform.system() == "Linux":
- self.label.setText(
+ self.show_error(
  "<strong>Dangerzone requires Podman</strong><br><br>"
  "Install it and retry."
  )
  else:
- self.label.setText(
+ self.show_error(
  "<strong>Dangerzone requires Docker Desktop</strong><br><br>"
  "<a href='https://www.docker.com/products/docker-desktop'>Download Docker Desktop</a>"
  ", install it, and open it."
  )
- self.buttons.show()
+
  elif state == "not_running":
  if platform.system() == "Linux":
  # "not_running" here means that the `podman image ls` command failed.
  message = (
  "<strong>Dangerzone requires Podman</strong><br><br>"
  "Podman is installed but cannot run properly. See errors below"
  )
- if error:
- self.traceback.set_content(error)
-
- self.label.setText(message)
-
  else:
- self.label.setText(
+ message = (
  "<strong>Dangerzone requires Docker Desktop</strong><br><br>"
  "Docker is installed but isn't running.<br><br>"
  "Open Docker and make sure it's running in the background."
  )
- self.buttons.show()
+ self.show_error(message, error)
  else:
- self.label.setText(
+ self.show_message(
  "Installing the Dangerzone container image.<br><br>"
  "This might take a few minutes..."
  )
- self.buttons.hide()
- self.traceback.setVisible(False)
  self.install_container_t = InstallContainerThread(self.dangerzone)
- self.install_container_t.finished.connect(self.finished)
+ self.install_container_t.finished.connect(self.installation_finished)
  self.install_container_t.start()
 
 

dangerzone/isolation_provider/base.py

@@ -93,6 +93,10 @@ def __init__(self) -> None:
  else:
  self.proc_stderr = subprocess.DEVNULL
 
+ @staticmethod
+ def is_runtime_available() -> bool:
+ return True
+
  @abstractmethod
  def install(self) -> bool:
  pass

dangerzone/isolation_provider/container.py

@@ -30,6 +30,21 @@ def __init__(self, container_tech: str) -> None:
  super().__init__(f"{container_tech} is not installed")
 
 
+class NotAvailableContainerTechException(Exception):
+ def __init__(self, container_tech: str, error: str) -> None:
+ self.error = error
+ self.container_tech = container_tech
+ super().__init__(f"{container_tech} is not available")
+
+
+class ImageNotPresentException(Exception):
+ pass
+
+
+class ImageInstallationException(Exception):
+ pass
+
+
 class Container(IsolationProvider):
  # Name of the dangerzone container
  CONTAINER_NAME = "dangerzone.rocks/dangerzone"
@@ -156,7 +171,7 @@ def install() -> bool:
  startupinfo=get_subprocess_startupinfo(),
  )
 
- chunk_size = 10240
+ chunk_size = 4 << 20
  compressed_container_path = get_resource_path("container.tar.gz")
  with gzip.open(compressed_container_path) as f:
  while True:
@@ -166,19 +181,42 @@ def install() -> bool:
  p.stdin.write(chunk)
  else:
  break
- p.communicate()
+ _, err = p.communicate()
+ if p.returncode < 0:
+ if err:
+ error = err.decode()
+ else:
+ error = "No output"
+ raise ImageInstallationException(
+ f"Could not install container image: {error}"
+ )
 
- if not Container.is_container_installed():
- log.error("Failed to install the container image")
+ if not Container.is_container_installed(raise_on_error=True):
  return False
 
  log.info("Container image installed")
  return True
 
  @staticmethod
- def is_container_installed() -> bool:
+ def is_runtime_available() -> bool:
+ container_runtime = Container.get_runtime()
+ runtime_name = Container.get_runtime_name()
+ # Can we run `docker/podman image ls` without an error
+ with subprocess.Popen(
+ [container_runtime, "image", "ls"],
+ stdout=subprocess.DEVNULL,
+ stderr=subprocess.PIPE,
+ startupinfo=get_subprocess_startupinfo(),
+ ) as p:
+ _, stderr = p.communicate()
+ if p.returncode != 0:
+ raise NotAvailableContainerTechException(runtime_name, stderr.decode())
+ return True
+
+ @staticmethod
+ def is_container_installed(raise_on_error: bool = False) -> bool:
  """
- See if the podman container is installed. Linux only.
+ See if the container is installed.
  """
  # Get the image id
  with open(get_resource_path("image-id.txt")) as f:
@@ -203,8 +241,18 @@ def is_container_installed() -> bool:
  if found_image_id in expected_image_ids:
  installed = True
  elif found_image_id == "":
- pass
+ if raise_on_error:
+ raise ImageNotPresentException(
+ "Image is not listed after installation. Bailing out."
+ )
  else:
+ msg = (
+ f"{Container.CONTAINER_NAME} images found, but IDs do not match."
+ f"Found: {found_image_id}, Expected: {','.join(expected_image_ids)}"
+ )
+ if raise_on_error:
+ raise ImageNotPresentException(msg)
+ log.info(msg)
  log.info("Deleting old dangerzone container image")
 
  try:

dangerzone/util.py

@@ -2,6 +2,7 @@
 import platform
 import subprocess
 import sys
+import traceback
 import unicodedata
 
 import appdirs
@@ -117,3 +118,13 @@ def is_safe(chr: str) -> bool:
  else:
  sanitized_str += "�"
  return sanitized_str
+
+
+def format_exception(e: Exception) -> str:
+ # The signature of traceback.format_exception has changed in python 3.10
+ if sys.version_info < (3, 10):
+ output = traceback.format_exception(*sys.exc_info())
+ else:
+ output = traceback.format_exception(e)
+
+ return "".join(output)