resolves #164 un-hardcode list of Windows versions

Partially resolves #138 (support for insider base image is still missing)

This commit:
1. Drops the list of valid Windows versions. Instead, ue4-docker now trusts user input and will fail during image download if user enters something nonexistent
2. Drops 1603->ltsc2016, 1809->ltsc2019 and 2009->20H2 renaming. Instead, ue4-docker directly maps host OS release to Windows Server Core image tag
3. However, ue4-docker now uses advanced logic to determine host OS release. It tries to use DisplayName registry key and fallbacks to ReleaseId if DisplayName doesn't exist. This allows to properly detect 20H2 and 21H1 releases.

On the negative side, some checks are lost:
1. It is no longer possible to check that container version is newer that host OS. Though is should still be rejected by Hyper-V
2. ue4-docker no longer prevents user from using suffix that collides with Windows Server Core image tags

ue4docker/build.py

@@ -112,22 +112,23 @@ def build():
 			# Provide the user with feedback so they are aware of the Windows-specific values being used
 			logger.info('WINDOWS CONTAINER SETTINGS', False)
 			logger.info('Isolation mode:               {}'.format(config.isolation), False)
-			logger.info('Base OS image tag:            {} (host OS is {})'.format(config.basetag, WindowsUtils.systemStringShort()), False)
+			logger.info('Base OS image tag:            {}'.format(config.basetag), False)
+			logger.info('Host OS:                      {}'.format(WindowsUtils.systemString()), False)
 			logger.info('Memory limit:                 {}'.format('No limit' if config.memLimit is None else '{:.2f}GB'.format(config.memLimit)), False)
 			logger.info('Detected max image size:      {:.0f}GB'.format(DockerUtils.maxsize()), False)
 			logger.info('Directory to copy DLLs from:  {}\n'.format(config.dlldir), False)
-			
+
 			# Verify that the specified base image tag is not a release that has reached End Of Life (EOL)
-			if WindowsUtils.isEndOfLifeWindowsVersion(config.basetag) == True:
+			if not config.ignoreEOL and WindowsUtils.isEndOfLifeWindowsVersion(config.basetag):
 				logger.error('Error: detected EOL base OS image tag: {}'.format(config.basetag), False)
 				logger.error('This version of Windows has reached End Of Life (EOL), which means', False)
 				logger.error('Microsoft no longer supports or maintains container base images for it.', False)
 				logger.error('You will need to use a base image tag for a supported version of Windows.', False)
 				sys.exit(1)
-			
+
 			# Verify that the host OS is not a release that is blacklisted due to critical bugs
-			if config.ignoreBlacklist == False and WindowsUtils.isBlacklistedWindowsVersion() == True:
-				logger.error('Error: detected blacklisted host OS version: {}'.format(WindowsUtils.systemStringShort()), False)
+			if not config.ignoreBlacklist and WindowsUtils.isBlacklistedWindowsVersion():
+				logger.error('Error: detected blacklisted host OS version: {}'.format(WindowsUtils.systemString()), False)
 				logger.error('', False)
 				logger.error('This version of Windows contains one or more critical bugs that', False)
 				logger.error('render it incapable of successfully building UE4 container images.', False)
@@ -136,15 +137,10 @@ def build():
 				logger.error('For more information, see:', False)
 				logger.error('https://unrealcontainers.com/docs/concepts/windows-containers', False)
 				sys.exit(1)
-
-			# Verify that the user is not attempting to build images with a newer kernel version than the host OS
-			if WindowsUtils.isNewerBaseTag(config.hostBasetag, config.basetag):
-				logger.error('Error: cannot build container images with a newer kernel version than that of the host OS!')
-				sys.exit(1)
-
+
 			# Check if the user is building a different kernel version to the host OS but is still copying DLLs from System32
-			differentKernels = WindowsUtils.isInsiderPreview() or config.basetag != config.hostBasetag
-			if config.pullPrerequisites == False and differentKernels == True and config.dlldir == config.defaultDllDir:
+			differentKernels = config.basetag != config.hostBasetag
+			if not config.pullPrerequisites and differentKernels and config.dlldir == config.defaultDllDir:
 				logger.error('Error: building images with a different kernel version than the host,', False)
 				logger.error('but a custom DLL directory has not specified via the `-dlldir=DIR` arg.', False)
 				logger.error('The DLL files will be the incorrect version and the container OS will', False)
@@ -239,7 +235,7 @@ def build():
 			# (This is the only image that does not use any user-supplied tag suffix, since the tag always reflects any customisations)
 			prereqsArgs = ['--build-arg', 'BASEIMAGE=' + config.baseImage]
 			if config.containerPlatform == 'windows':
-				prereqsArgs = prereqsArgs + ['--build-arg', 'HOST_VERSION=' + WindowsUtils.getWindowsBuild()]
+				prereqsArgs = prereqsArgs + ['--build-arg', 'HOST_BUILD=' + str(WindowsUtils.getWindowsBuild())]
 
 			# Build or pull the UE4 build prerequisites image (don't pull it if we're copying Dockerfiles to an output directory)
 			if config.layoutDir is None and config.pullPrerequisites == True:

ue4docker/diagnostics/base.py

@@ -60,8 +60,7 @@ def _generateWindowsBuildArgs(self, logger, basetagOverride=None, isolationOverr
 		'''
 
 		# Determine the appropriate container image base tag for the host system release unless the user specified a base tag
-		buildArgs = []
-		defaultBaseTag = WindowsUtils.getReleaseBaseTag(WindowsUtils.getWindowsRelease())
+		defaultBaseTag = WindowsUtils.getWindowsRelease()
 		baseTag = basetagOverride if basetagOverride is not None else defaultBaseTag
 		buildArgs = ['--build-arg', 'BASETAG={}'.format(baseTag)]
 

ue4docker/diagnostics/diagnostic_maxsize.py

@@ -47,7 +47,7 @@ def run(self, logger, args=[]):
 			return False
 
 		# Verify that we are running Windows Server or Windows 10 version 1903 or newer
-		if WindowsUtils.getWindowsVersion()['patch'] < 18362:
+		if WindowsUtils.getWindowsBuild() < 18362:
 			logger.info('[maxsize] This diagnostic only applies to Windows Server and Windows 10 version 1903 and newer.', False)
 			return True
 

ue4docker/dockerfiles/ue4-build-prerequisites/windows/Dockerfile

@@ -20,11 +20,11 @@ RUN choco install -y 7zip curl && choco install -y python --version=3.7.5
 COPY *.dll C:\GatheredDlls\
 
 # Verify that the DLL files copied from the host can be loaded by the container OS
-ARG HOST_VERSION
+ARG HOST_BUILD
 RUN pip install pywin32
 COPY copy.py verify-host-dlls.py C:\
 RUN C:\copy.py "C:\GatheredDlls\*.dll" C:\Windows\System32\
-RUN python C:\verify-host-dlls.py %HOST_VERSION% C:\GatheredDlls
+RUN python C:\verify-host-dlls.py %HOST_BUILD% C:\GatheredDlls
 
 # Gather the required DirectX runtime files, since Windows Server Core does not include them
 RUN curl --progress-bar -L "https://download.microsoft.com/download/8/4/A/84A35BF1-DAFE-4AE8-82AF-AD2AE20B6B14/directx_Jun2010_redist.exe" --output %TEMP%\directx_redist.exe

ue4docker/dockerfiles/ue4-build-prerequisites/windows/verify-host-dlls.py

@@ -1,4 +1,5 @@
-import glob, os, platform, sys, win32api, winreg
+import glob, os, sys, win32api
+
 
 # Adapted from the code in this SO answer: <https://stackoverflow.com/a/7993095>
 def getDllVersion(dllPath):
@@ -10,20 +11,10 @@ def getDllVersion(dllPath):
 		info['FileVersionLS'] % 65536
 	)
 
-def getVersionRegKey(subkey):
-	key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, 'SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion')
-	value = winreg.QueryValueEx(key, subkey)
-	winreg.CloseKey(key)
-	return value[0]
-
-def getOsVersion():
-	version = platform.win32_ver()[1]
-	build = getVersionRegKey('BuildLabEx').split('.')[1]
-	return '{}.{}'.format(version, build)
 
 # Print the host and container OS build numbers
 print('Host OS build number:      {}'.format(sys.argv[1]))
-print('Container OS build number: {}'.format(getOsVersion()))
+print('Container OS build number: {}'.format(sys.getwindowsversion().build))
 sys.stdout.flush()
 
 # Verify each DLL file in the directory specified by our command-line argument

ue4docker/info.py

@@ -4,7 +4,7 @@
 
 def _osName(dockerInfo):
 	if platform.system() == 'Windows':
-		return WindowsUtils.systemStringLong()
+		return WindowsUtils.systemString()
 	elif platform.system() == 'Darwin':
 		return DarwinUtils.systemString()
 	else:

ue4docker/infrastructure/BuildConfiguration.py

@@ -92,6 +92,7 @@ def addArguments(parser):
 		parser.add_argument('--combine', action='store_true', help='Combine generated Dockerfiles into a single multi-stage build Dockerfile')
 		parser.add_argument('--monitor', action='store_true', help='Monitor resource usage during builds (useful for debugging)')
 		parser.add_argument('-interval', type=float, default=20.0, help='Sampling interval in seconds when resource monitoring has been enabled using --monitor (default is 20 seconds)')
+		parser.add_argument('--ignore-eol', action='store_true', help='Run builds even on EOL versions of Windows (advanced use only)')
 		parser.add_argument('--ignore-blacklist', action='store_true', help='Run builds even on blacklisted versions of Windows (advanced use only)')
 		parser.add_argument('-v', '--verbose', action='store_true', help='Enable verbose output during builds (useful for debugging)')
 
@@ -150,6 +151,7 @@ def __init__(self, parser, argv):
 		self.excludedComponents = set(self.args.exclude)
 		self.baseImage = None
 		self.prereqsTag = None
+		self.ignoreEOL = self.args.ignore_eol
 		self.ignoreBlacklist = self.args.ignore_blacklist
 		self.verbose = self.args.verbose
 		self.layoutDir = self.args.layout
@@ -226,30 +228,21 @@ def _generateWindowsConfig(self):
 		self.dlldir = self.args.dlldir if self.args.dlldir is not None else self.defaultDllDir
 
 		# Determine base tag for the Windows release of the host system
-		self.hostRelease = WindowsUtils.getWindowsRelease()
-		self.hostBasetag = WindowsUtils.getReleaseBaseTag(self.hostRelease)
+		self.hostBasetag = WindowsUtils.getWindowsRelease()
 
 		# Store the tag for the base Windows Server Core image
 		self.basetag = self.args.basetag if self.args.basetag is not None else self.hostBasetag
 		self.baseImage = 'mcr.microsoft.com/windows/servercore:' + self.basetag
 		self.prereqsTag = self.basetag
-
-		# Verify that any user-specified base tag is valid
-		if WindowsUtils.isValidBaseTag(self.basetag) == False:
-			raise RuntimeError('unrecognised Windows Server Core base image tag "{}", supported tags are {}'.format(self.basetag, WindowsUtils.getValidBaseTags()))
-
-		# Verify that any user-specified tag suffix does not collide with our base tags
-		if WindowsUtils.isValidBaseTag(self.suffix) == True:
-			raise RuntimeError('tag suffix cannot be any of the Windows Server Core base image tags: {}'.format(WindowsUtils.getValidBaseTags()))
-
+
 		# If the user has explicitly specified an isolation mode then use it, otherwise auto-detect
 		if self.args.isolation is not None:
 			self.isolation = self.args.isolation
 		else:
 
 			# If we are able to use process isolation mode then use it, otherwise fallback to the Docker daemon's default isolation mode
-			differentKernels = WindowsUtils.isInsiderPreview() or self.basetag != self.hostBasetag
-			hostSupportsProcess = WindowsUtils.isWindowsServer() or int(self.hostRelease) >= 1809
+			differentKernels = self.basetag != self.hostBasetag
+			hostSupportsProcess = WindowsUtils.supportsProcessIsolation()
 			dockerSupportsProcess = parse_version(DockerUtils.version()['Version']) >= parse_version('18.09.0')
 			if not differentKernels and hostSupportsProcess and dockerSupportsProcess:
 				self.isolation = 'process'