WindowsUtils.py

from .DockerUtils import DockerUtils
from .PackageUtils import PackageUtils
from pkg_resources import parse_version
import os, platform

if platform.system() == 'Windows':
	import winreg

# Import the `semver` package even when the conflicting `node-semver` package is present
semver = PackageUtils.importFile('semver', os.path.join(PackageUtils.getPackageLocation('semver'), 'semver.py'))

class WindowsUtils(object):
	
	# The latest Windows build version we recognise as a non-Insider build
	_latestReleaseBuild = 19042
	
	# The list of Windows Server Core base image tags that we recognise, in ascending version number order
	_validTags = ['ltsc2016', '1709', '1803', 'ltsc2019', '1903', '1909', '2004', '20H2']
	
	# The list of Windows Server and Windows 10 host OS releases that are blacklisted due to critical bugs
	# (See: <https://unrealcontainers.com/docs/concepts/windows-containers>)
	_blacklistedReleases = ['1903', '1909']
	
	# The list of Windows Server Core container image releases that are unsupported due to having reached EOL
	_eolReleases = ['1709']
	
	@staticmethod
	def _getVersionRegKey(subkey):
		'''
		Retrieves the specified Windows version key from the registry
		'''
		key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, 'SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion')
		value = winreg.QueryValueEx(key, subkey)
		winreg.CloseKey(key)
		return value[0]
	
	@staticmethod
	def requiredHostDlls(basetag):
		'''
		Returns the list of required host DLL files for the specified container image base tag
		'''
		
		# `ddraw.dll` is only required under Windows Server 2016 version 1607
		common = ['dsound.dll', 'opengl32.dll', 'glu32.dll']
		return ['ddraw.dll'] + common if basetag == 'ltsc2016' else common
	
	@staticmethod
	def requiredSizeLimit():
		'''
		Returns the minimum required image size limit (in GB) for Windows containers
		'''
		return 400.0
	
	@staticmethod
	def minimumRequiredVersion():
		'''
		Returns the minimum required version of Windows 10 / Windows Server, which is release 1607
		
		(1607 is the first build to support Windows containers, as per:
		<https://docs.microsoft.com/en-us/virtualization/windowscontainers/deploy-containers/version-compatibility>)
		'''
		return '10.0.14393'
	
	@staticmethod
	def systemStringShort():
		'''
		Generates a concise human-readable version string for the Windows host system
		'''
		return 'Windows {} version {}'.format(
			'Server' if WindowsUtils.isWindowsServer() else '10',
			WindowsUtils.getWindowsRelease()
		)
	
	@staticmethod
	def systemStringLong():
		'''
		Generates a verbose human-readable version string for the Windows host system
		'''
		return '{} Version {} (OS Build {}.{})'.format(
			WindowsUtils._getVersionRegKey('ProductName'),
			WindowsUtils.getWindowsRelease(),
			WindowsUtils.getWindowsVersion()['patch'],
			WindowsUtils._getVersionRegKey('UBR')
		)
	
	@staticmethod
	def getWindowsVersion():
		'''
		Returns the version information for the Windows host system as a semver instance
		'''
		return semver.parse(platform.win32_ver()[1])
	
	@staticmethod
	def getWindowsRelease():
		'''
		Determines the Windows 10 / Windows Server release (1607, 1709, 1803, etc.) of the Windows host system
		'''
		return WindowsUtils._getVersionRegKey('ReleaseId')
	
	@staticmethod
	def getWindowsBuild():
		'''
		Returns the full Windows version number as a string, including the build number
		'''
		version = platform.win32_ver()[1]
		build = WindowsUtils._getVersionRegKey('BuildLabEx').split('.')[1]
		return '{}.{}'.format(version, build)
	
	@staticmethod
	def isBlacklistedWindowsVersion(release=None):
		'''
		Determines if the specified Windows release is one with bugs that make it unsuitable for use
		(defaults to checking the host OS release if one is not specified)
		'''
		dockerVersion = parse_version(DockerUtils.version()['Version'])
		release = WindowsUtils.getWindowsRelease() if release is None else release
		return release in WindowsUtils._blacklistedReleases and dockerVersion < parse_version('19.03.6')
	
	@staticmethod
	def isEndOfLifeWindowsVersion(release=None):
		'''
		Determines if the specified Windows release is one that has reached End Of Life (EOL)
		(defaults to checking the host OS release if one is not specified)
		'''
		release = WindowsUtils.getWindowsRelease() if release is None else release
		return release in WindowsUtils._eolReleases
	
	@staticmethod
	def isSupportedWindowsVersion():
		'''
		Verifies that the Windows host system meets our minimum Windows version requirements
		'''
		return semver.compare(platform.win32_ver()[1], WindowsUtils.minimumRequiredVersion()) >= 0
	
	@staticmethod
	def isWindowsServer():
		'''
		Determines if the Windows host system is Windows Server
		'''
		return 'Windows Server' in WindowsUtils._getVersionRegKey('ProductName')
	
	@staticmethod
	def isInsiderPreview():
		'''
		Determines if the Windows host system is a Windows Insider preview build
		'''
		version = WindowsUtils.getWindowsVersion()
		return version['patch'] > WindowsUtils._latestReleaseBuild
	
	@staticmethod
	def getReleaseBaseTag(release):
		'''
		Retrieves the tag for the Windows Server Core base image matching the specified Windows 10 / Windows Server release
		'''
		
		# For Windows Insider preview builds, build the latest release tag
		if WindowsUtils.isInsiderPreview():
			return WindowsUtils._validTags[-1]
		
		# This lookup table is based on the list of valid tags from <https://hub.docker.com/r/microsoft/windowsservercore/>
		return {
			'1709': '1709',
			'1803': '1803',
			'1809': 'ltsc2019',
			'1903': '1903',
			'1909': '1909',
			'2004': '2004',
			'2009': '20H2',
			'20H2': '20H2'
		}.get(release, 'ltsc2016')
	
	@staticmethod
	def getValidBaseTags():
		'''
		Returns the list of valid tags for the Windows Server Core base image, in ascending chronological release order
		'''
		return WindowsUtils._validTags
	
	@staticmethod
	def isValidBaseTag(tag):
		'''
		Determines if the specified tag is a valid Windows Server Core base image tag
		'''
		return tag in WindowsUtils._validTags
	
	@staticmethod
	def isNewerBaseTag(older, newer):
		'''
		Determines if the base tag `newer` is chronologically newer than the base tag `older`
		'''
		return WindowsUtils._validTags.index(newer) > WindowsUtils._validTags.index(older)