Nice colored unsupported distro messages

BUILD_LINUX.md

@@ -100,7 +100,9 @@ a Qt install.
 ### Using the system's Qt
 
 The system's Qt can be used, if the development packages are installed, by setting the
-`VIRCADIA_USE_SYSTEM_QT` environment variable. The minimum recommended version is Qt 5.15.0.
+`VIRCADIA_USE_SYSTEM_QT` environment variable. The minimum recommended version is Qt 5.15.2, which is
+also the last version available in the Qt 5 branch. It is expected that Linux distributions will have
+Qt 5.15.2 available for a long time.
 
 ### Compiling
 

CMakeLists.txt

@@ -77,7 +77,7 @@ endif()
 if (HIFI_ANDROID)
     execute_process(
         COMMAND ${HIFI_PYTHON_EXEC} ${CMAKE_CURRENT_SOURCE_DIR}/prebuild.py --release-type ${RELEASE_TYPE} --android ${HIFI_ANDROID_APP} --build-root ${CMAKE_BINARY_DIR}
-        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} RESULTS_VARIABLE PREBUILD_RET
     )
 else()
     set(VCPKG_BUILD_TYPE_PARAM "")
@@ -86,7 +86,7 @@ else()
     endif()
     execute_process(
         COMMAND ${HIFI_PYTHON_EXEC} ${CMAKE_CURRENT_SOURCE_DIR}/prebuild.py --release-type ${RELEASE_TYPE} --build-root ${CMAKE_BINARY_DIR} ${VCPKG_BUILD_TYPE_PARAM}
-        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} RESULTS_VARIABLE PREBUILD_RET
     )
     # squelch the Policy CMP0074 warning without requiring an update to cmake 3.12.
     if (CMAKE_VERSION VERSION_GREATER_EQUAL 3.12)
@@ -94,6 +94,9 @@ else()
     endif()
 endif()
 
+if ("${PREBUILD_RET}" GREATER 0)
+  message(FATAL_ERROR "prebuild.py failed with error ${PREBUILD_RET}")
+endif()
 if(NOT EXISTS "${CMAKE_BINARY_DIR}/vcpkg.cmake")
     message(FATAL_ERROR "vcpkg configuration missing.")
 endif()

hifi_qt.py

@@ -37,6 +37,29 @@ import functools
 
 print = functools.partial(print, flush=True)
 
+def unsupported_error():
+    import distro
+    cpu_architecture = platform.machine()
+
+    print('')
+    hifi_utils.color('red')
+    print("Sorry, we don't have a prebuilt Qt package for " + distro.name(pretty=True) + " on " + cpu_architecture + ".")
+    hifi_utils.color('white')
+    print('')
+    print("If this is a recent distribution, dating from 2021 or so, you can try building")
+    print("against the system Qt by running this command, and trying again:")
+    print("    export VIRCADIA_USE_SYSTEM_QT=1")
+    print("")
+    hifi_utils.color('clear')
+    print("If you'd like to try to build Qt from source either for building Vircadia, or")
+    print("to contribute a prebuilt package for your distribution, please see the")
+    print("documentation at: ", end='')
+    hifi_utils.color('blue')
+    print("https://github.com/vircadia/vircadia/tree/master/tools/qt-builder")
+    hifi_utils.color('clear')
+    print('')
+
+    raise hifi_utils.SilentFatalError(2)
 # Encapsulates the vcpkg system
 class QtDownloader:
     CMAKE_TEMPLATE = """
@@ -155,10 +178,11 @@ endif()
                         print("Sorry, " + distro.name(pretty=True) + " is old and won't be officially supported. Please consider upgrading.");
                         raise Exception('UNKNOWN LINUX DISTRO VERSION!!!')
                 else:
-                    print("Sorry, " + distro.name(pretty=True) + " is not supported on x86_64. Please consider helping us out.")
-                    print("It's also possible to build Qt for your distribution, please see the documentation at:")
-                    print("https://github.com/vircadia/vircadia/tree/master/tools/qt-builder")
-                    raise Exception('UNKNOWN LINUX VERSION!!!')
+                    unsupported_error()
+#                    print("Sorry, " + distro.name(pretty=True) + " is not supported on x86_64. Please consider helping us out.")
+#                    print("It's also possible to build Qt for your distribution, please see the documentation at:")
+#                    print("https://github.com/vircadia/vircadia/tree/master/tools/qt-builder")
+#                    raise Exception('UNKNOWN LINUX VERSION!!!')
             elif 'aarch64' == cpu_architecture:
                 if distro.id() == 'ubuntu':
                     u_major = int( distro.major_version() )

hifi_utils.py

@@ -16,6 +16,18 @@ import functools
 
 print = functools.partial(print, flush=True)
 
+ansi_colors = {
+    'black' : 30,
+    'red': 31,
+    'green': 32,
+    'yellow': 33,
+    'blue': 34,
+    'magenta': 35,
+    'cyan': 36,
+    'white': 37,
+    'clear': 0
+}
+
 def scriptRelative(*paths):
     scriptdir = os.path.dirname(os.path.realpath(sys.argv[0]))
     result = os.path.join(scriptdir, *paths)
@@ -125,3 +137,17 @@ def downloadAndExtract(url, destPath, hash=None, hasher=hashlib.sha512(), isZip=
 def readEnviromentVariableFromFile(buildRootDir, var):
     with open(os.path.join(buildRootDir, '_env', var + ".txt")) as fp:
         return fp.read()
+
+class SilentFatalError(Exception):
+    """Thrown when some sort of fatal condition happened, and we already reported it to the user.
+    This excecption exists to give a chance to run any cleanup needed before exiting.
+
+    It should be handled at the bottom of the call stack, where the only action is to call
+    sys.exit(ex.exit_code)
+    """
+    def __init__(self, exit_code):
+        self.exit_code = exit_code
+
+def color(color_name):
+    # Ideally we'd use the termcolor module, but this avoids adding it as a dependency.
+    print("\033[1;{}m".format(ansi_colors[color_name]), end='')

prebuild.py

@@ -207,4 +207,7 @@ def main():
     logger.info('end')
 
 print(sys.argv)
-main()
+try:
+    main()
+except hifi_utils.SilentFatalError as fatal_ex:
+    sys.exit(fatal_ex.exit_code)