windows: fix colors and bold text not rendering (#8872)

Fixes #8848.

certbot/CHANGELOG.md

@@ -24,6 +24,7 @@ Certbot adheres to [Semantic Versioning](https://semver.org/).
 
 * Fix TypeError due to incompatibility with lexicon >= v3.6.0
 * Installers (e.g. nginx, Apache) were being restarted unnecessarily after dry-run renewals.
+* Colors and bold text should properly render in all supported versions of Windows.
 
 More details about these changes can be found on our GitHub repo.
 

certbot/certbot/_internal/main.py

@@ -1519,6 +1519,9 @@ def main(cli_args=None):
     logger.debug("Arguments: %r", cli_args)
     logger.debug("Discovered plugins: %r", plugins)
 
+    # Some releases of Windows require escape sequences to be enable explicitly
+    misc.prepare_virtual_console()
+
     # note: arg parser internally handles --help (and exits afterwards)
     args = cli.prepare_and_parse_args(plugins, cli_args)
     config = configuration.NamespaceConfig(args)

certbot/certbot/compat/misc.py

@@ -17,6 +17,8 @@ from certbot.compat import os
 
 try:
     from win32com.shell import shell as shellwin32
+    from win32console import GetStdHandle, STD_OUTPUT_HANDLE
+    from pywintypes import error as pywinerror
     POSIX_MODE = False
 except ImportError:  # pragma: no cover
     POSIX_MODE = True
@@ -39,6 +41,26 @@ def raise_for_non_administrative_windows_rights() -> None:
         raise errors.Error('Error, certbot must be run on a shell with administrative rights.')
 
 
+def prepare_virtual_console() -> None:
+    """
+    On Windows, ensure that Console Virtual Terminal Sequences are enabled.
+
+    """
+    if POSIX_MODE:
+        return
+
+    # https://docs.microsoft.com/en-us/windows/console/setconsolemode
+    ENABLE_VIRTUAL_TERMINAL_PROCESSING = 0x0004
+
+    # stdout/stderr will be the same console screen buffer, but this could return None or raise
+    try:
+        h = GetStdHandle(STD_OUTPUT_HANDLE)
+        if h:
+            h.SetConsoleMode(h.GetConsoleMode() | ENABLE_VIRTUAL_TERMINAL_PROCESSING)
+    except pywinerror:
+        logger.debug("Failed to set console mode", exc_info=True)
+
+
 def readline_with_timeout(timeout: float, prompt: str) -> str:
     """
     Read user input to return the first line entered, or raise after specified timeout.