Update downloader: modernized, includes hashlib and other fixes from …

…recent releases. re nvaccess#3504

Modernized Jamie Teh's downloader class to include file hashes and other changes from recent releases. Testing shows it is working as advertised.

source/downloader.py

@@ -2,14 +2,16 @@
 #A part of NonVisual Desktop Access (NVDA)
 #This file is covered by the GNU General Public License.
 #See the file COPYING for more details.
-#Copyright (C) 2013 NV Access Limited
+#Copyright (C) 2013-2017 NV Access Limited, Joseph Lee
 
 """Utilities for downloading files.
 """
 
+import os
 import tempfile
 import urllib
 import threading
+import hashlib
 import wx
 import gui
 from logHandler import log
@@ -36,14 +38,17 @@ class FileDownloader(object):
 	#: @type: basestring
 	errorMessage = None
 
-	def __init__(self, urls, parent=None):
+	def __init__(self, urls, fileHash=None, parent=None):
 		"""Constructor.
 		@param urls: URLs to try for the file.
 		@type urls: list of str
+		@param fileHash: The SHA-1 hash of the file as a hex string.
+		@type fileHash: basestring
 		@param parent: The parent window for any dialogs.
 		@type parent: C{wx.Window}
 		"""
 		self.urls = urls
+		self.fileHash = fileHash
 		if not parent:
 			parent = gui.mainFrame
 		self.parent = parent
@@ -74,7 +79,8 @@ def _guiExec(self, func, *args):
 		self._guiExecFunc = func
 		self._guiExecArgs = args
 		if not self._guiExecTimer.IsRunning():
-			self._guiExecTimer.Start(50, True)
+			# #6127: Timers must be manipulated from the main thread.
+			wx.CallAfter(self._guiExecTimer.Start, 50, True)
 
 	def _guiExecNotify(self):
 		self._guiExecFunc(*self._guiExecArgs)
@@ -112,6 +118,8 @@ def _download(self, url):
 		remote.fp._sock.settimeout(120)
 		size = int(remote.headers["content-length"])
 		local = file(self.destPath, "wb")
+		if self.fileHash:
+			hasher = hashlib.sha1()
 		self._guiExec(self._downloadReport, 0, size)
 		read = 0
 		chunk=DOWNLOAD_BLOCK_SIZE
@@ -127,9 +135,13 @@ def _download(self, url):
 			if self._shouldCancel:
 				return
 			local.write(block)
+			if self.fileHash:
+				hasher.update(block)
 			self._guiExec(self._downloadReport, read, size)
 		if read < size:
 			raise RuntimeError("Content too short")
+		if self.fileHash and hasher.hexdigest() != self.fileHash:
+			raise RuntimeError("Content has incorrect file hash")
 		self._guiExec(self._downloadReport, read, size)
 
 	def _downloadReport(self, read, size):

source/updateCheck.py

@@ -15,6 +15,7 @@
 if not versionInfo.updateVersionType:
 	raise RuntimeError("No update version type, update checking not supported")
 
+import ctypes
 import winVersion
 import os
 import threading
@@ -37,8 +38,6 @@
 CHECK_INTERVAL = 86400 # 1 day
 #: The time to wait before retrying a failed check.
 RETRY_INTERVAL = 600 # 10 min
-#: The download block size in bytes.
-DOWNLOAD_BLOCK_SIZE = 8192 # 8 kb
 
 #: Persistent state information.
 #: @type: dict
@@ -254,141 +253,11 @@ class UpdateDownloader(FileDownloader):
 	"""Download and start installation of an updated version of NVDA, presenting appropriate user interface.
 	"""
 
-<<<<<<< 89e9721cfdeba19f0508a99f716c4b4f72cf74f9
-	def __init__(self, urls, fileHash=None):
-		"""Constructor.
-		@param urls: URLs to try for the update file.
-		@type urls: list of str
-		@param fileHash: The SHA-1 hash of the file as a hex string.
-		@type fileHash: basestring
-		"""
-		self.urls = urls
-		self.destPath = tempfile.mktemp(prefix="nvda_update_", suffix=".exe")
-		self.fileHash = fileHash
-
-	def start(self):
-		"""Start the download.
-		"""
-		self._shouldCancel = False
-		# Use a timer because timers aren't re-entrant.
-		self._guiExecTimer = wx.PyTimer(self._guiExecNotify)
-		gui.mainFrame.prePopup()
-		# Translators: The title of the dialog displayed while downloading an NVDA update.
-		self._progressDialog = wx.ProgressDialog(_("Downloading Update"),
-			# Translators: The progress message indicating that a connection is being established.
-			_("Connecting"),
-			# PD_AUTO_HIDE is required because ProgressDialog.Update blocks at 100%
-			# and waits for the user to press the Close button.
-			style=wx.PD_CAN_ABORT | wx.PD_ELAPSED_TIME | wx.PD_REMAINING_TIME | wx.PD_AUTO_HIDE,
-			parent=gui.mainFrame)
-		self._progressDialog.Raise()
-		t = threading.Thread(target=self._bg)
-		t.daemon = True
-		t.start()
-
-	def _guiExec(self, func, *args):
-		self._guiExecFunc = func
-		self._guiExecArgs = args
-		if not self._guiExecTimer.IsRunning():
-			# #6127: Timers must be manipulated from the main thread.
-			wx.CallAfter(self._guiExecTimer.Start, 50, True)
-
-	def _guiExecNotify(self):
-		self._guiExecFunc(*self._guiExecArgs)
-
-	def _bg(self):
-		success=False
-		for url in self.urls:
-			try:
-				self._download(url)
-			except:
-				log.debugWarning("Error downloading %s" % url, exc_info=True)
-			else: #Successfully downloaded or canceled
-				if not self._shouldCancel:
-					success=True
-				break
-		else:
-			# None of the URLs succeeded.
-			self._guiExec(self._error)
-			return
-		if not success:
-			try:
-				os.remove(self.destPath)
-			except OSError:
-				pass
-			return
-		self._guiExec(self._downloadSuccess)
-
-	def _download(self, url):
-		remote = urllib.urlopen(url)
-		if remote.code != 200:
-			raise RuntimeError("Download failed with code %d" % remote.code)
-		# #2352: Some security scanners such as Eset NOD32 HTTP Scanner
-		# cause huge read delays while downloading.
-		# Therefore, set a higher timeout.
-		remote.fp._sock.settimeout(120)
-		size = int(remote.headers["content-length"])
-		local = file(self.destPath, "wb")
-		if self.fileHash:
-			hasher = hashlib.sha1()
-		self._guiExec(self._downloadReport, 0, size)
-		read = 0
-		chunk=DOWNLOAD_BLOCK_SIZE
-		while True:
-			if self._shouldCancel:
-				return
-			if size -read <chunk:
-				chunk =size -read
-			block = remote.read(chunk)
-			if not block:
-				break
-			read += len(block)
-			if self._shouldCancel:
-				return
-			local.write(block)
-			if self.fileHash:
-				hasher.update(block)
-			self._guiExec(self._downloadReport, read, size)
-		if read < size:
-			raise RuntimeError("Content too short")
-		if self.fileHash and hasher.hexdigest() != self.fileHash:
-			raise RuntimeError("Content has incorrect file hash")
-		self._guiExec(self._downloadReport, read, size)
-
-	def _downloadReport(self, read, size):
-		if self._shouldCancel:
-			return
-		percent = int(float(read) / size * 100)
-		# Translators: The progress message indicating that a download is in progress.
-		cont, skip = self._progressDialog.Update(percent, _("Downloading"))
-		if not cont:
-			self._shouldCancel = True
-			self._stopped()
-
-	def _stopped(self):
-		self._guiExecTimer = None
-		self._guiExecFunc = None
-		self._guiExecArgs = None
-		self._progressDialog.Hide()
-		self._progressDialog.Destroy()
-		self._progressDialog = None
-		# Not sure why, but this doesn't work if we call it directly here.
-		wx.CallLater(50, gui.mainFrame.postPopup)
-
-	def _error(self):
-		self._stopped()
-		gui.messageBox(
-			# Translators: A message indicating that an error occurred while downloading an update to NVDA.
-			_("Error downloading update."),
-			_("Error"),
-			wx.OK | wx.ICON_ERROR)
-=======
 	destSuffix = ".exe"
 	# Translators: The title of the dialog displayed while downloading an NVDA update.
 	progressTitle = _("Downloading Update")
 	# Translators: A message indicating that an error occurred while downloading an update to NVDA.
 	errorMessage = _("Error downloading update.")
->>>>>>> updateCheck.UpdateDownloader: Use new FileDownloader class.
 
 	def onSuccess(self):
 		# Translators: The message presented when the update has been successfully downloaded